Cementless Hydroxyapatite Coated Hip Prostheses

PubMed Central

Herrera, Antonio; Mateo, Jesús; Gil-Albarova, Jorge; Lobo-Escolar, Antonio; Ibarz, Elena; Gabarre, Sergio; Más, Yolanda

2015-01-01

More than twenty years ago, hydroxyapatite (HA), calcium phosphate ceramics, was introduced as a coating for cementless hip prostheses. The choice of this ceramic is due to its composition being similar to organic apatite bone crystals. This ceramic is biocompatible, bioactive, and osteoconductive. These qualities facilitate the primary stability and osseointegration of implants. Our surgical experience includes the implantation of more than 4,000 cementless hydroxyapatite coated hip prostheses since 1990. The models implanted are coated with HA in the acetabulum and in the metaphyseal area of the stem. The results corresponding to survival and stability of implants were very satisfactory in the long-term. From our experience, HA-coated hip implants are a reliable alternative which can achieve long term survival, provided that certain requirements are met: good design selection, sound choice of bearing surfaces based on patient life expectancy, meticulous surgical technique, and indications based on adequate bone quality. PMID:25802848

Numeric simulation of bone remodelling patterns after implantation of a cementless straight stem.

PubMed

Lerch, Matthias; Windhagen, Henning; Stukenborg-Colsman, Christina M; Kurtz, Agnes; Behrens, Bernd A; Almohallami, Amer; Bouguecha, Anas

2013-12-01

For further development of better bone-preserving implants in total hip arthroplasty (THA), we need to look back and analyse established and clinically approved implants to find out what made them successful. Finite element analysis can help do this by simulating periprosthetic bone remodelling under different conditions. Our aim was thus to establish a numerical model of the cementless straight stem for which good long-term results have been obtained. We performed a numeric simulation of a cementless straight stem, which has been successfully used in its unaltered form since 1986/1987. We have 20 years of experience with this THA system and implanted it 555 times in 2012. We performed qualitative and quantitative validation using bone density data derived from a prospective dual-energy X-ray absorptiometry (DEXA) investigation. Bone mass loss converged to 9.25% for the entire femur. No change in bone density was calculated distal to the tip of the prosthesis. Bone mass decreased by 46.2% around the proximal half of the implant and by 7.6% in the diaphysis. The numeric model was in excellent agreement with DEXA data except for the calcar region, where deviation was 67.7%. The higher deviation in the calcar region is possibly a sign of the complex interactions between the titanium coating on the stem and the surrounding bone. We developed a validated numeric model to simulate bone remodelling for different stem-design modifications. We recommend that new THA implants undergo critical numeric simulation before clinical application.

Effects of an AST program on US titanium story

NASA Technical Reports Server (NTRS)

Fitzsimmons, R. D.

1980-01-01

The singular importance of titanium as the primary structural material for an efficient advanced supersonic transport (AST) is outlined. The advantages of titanium over other metals are shown to apply to future subsonic aircraft as well as for supersonic designs. The cost problem of titanium is addressed and shown to be markedly reduced by the emerging technologies of superplastic forming/diffusion bonding sandwich, hot isostatic pressing of titanium powders, and isothermal forgings if demonstration programs should validate preliminary findings. The impact of a U.S. AST program on the United States titanium supply and demand picture is postulated.

New Nomenclatures for Heat Treatments of Additively Manufactured Titanium Alloys

NASA Astrophysics Data System (ADS)

Baker, Andrew H.; Collins, Peter C.; Williams, James C.

2017-07-01

The heat-treatment designations and microstructure nomenclatures for many structural metallic alloys were established for traditional metals processing, such as casting, hot rolling or forging. These terms do not necessarily apply for additively manufactured (i.e., three-dimensionally printed or "3D printed") metallic structures. The heat-treatment terminology for titanium alloys generally implies the heat-treatment temperatures and their sequence relative to a thermomechanical processing step (e.g., forging, rolling). These designations include: β-processing, α + β-processing, β-annealing, duplex annealing and mill annealing. Owing to the absence of a thermomechanical processing step, these traditional designations can pose a problem when titanium alloys are first produced via additive manufacturing, and then heat-treated. This communication proposes new nomenclatures for heat treatments of additively manufactured titanium alloys, and uses the distinct microstructural features to provide a correlation between traditional nomenclature and the proposed nomenclature.

The Otto Aufranc Award: Enhanced Biocompatibility of Stainless Steel Implants by Titanium Coating and Microarc Oxidation

PubMed Central

Lim, Young Wook; Kwon, Soon Yong; Sun, Doo Hoon

2010-01-01

Background Stainless steel is one of the most widely used biomaterials for internal fixation devices, but is not used in cementless arthroplasty implants because a stable oxide layer essential for biocompatibility cannot be formed on the surface. We applied a Ti electron beam coating, to form oxide layer on the stainless steel surface. To form a thicker oxide layer, we used a microarc oxidation process on the surface of Ti coated stainless steel. Modification of the surface using Ti electron beam coating and microarc oxidation could improve the ability of stainless steel implants to osseointegrate. Questions/purposes The ability of cells to adhere to grit-blasted, titanium-coated, microarc-oxidated stainless steel in vitro was compared with that of two different types of surface modifications, machined and titanium-coated, and microarc-oxidated. Methods We performed energy-dispersive x-ray spectroscopy and scanning electron microscopy investigations to assess the chemical composition and structure of the stainless steel surfaces and cell morphology. The biologic responses of an osteoblastlike cell line (SaOS-2) were examined by measuring proliferation (cell proliferation assay), differentiation (alkaline phosphatase activity), and attraction ability (cell migration assay). Results Cell proliferation, alkaline phosphatase activity, migration, and adhesion were increased in the grit-blasted, titanium-coated, microarc-oxidated group compared to the two other groups. Osteoblastlike cells on the grit-blasted, titanium-coated, microarc-oxidated surface were strongly adhered, and proliferated well compared to those on the other surfaces. Conclusions The surface modifications we used (grit blasting, titanium coating, microarc oxidation) enhanced the biocompatibility (proliferation and migration of osteoblastlike cells) of stainless steel. Clinical Relevance This process is not unique to stainless steel; it can be applied to many metals to improve their biocompatibility

The Otto Aufranc Award: enhanced biocompatibility of stainless steel implants by titanium coating and microarc oxidation.

PubMed

Lim, Young Wook; Kwon, Soon Yong; Sun, Doo Hoon; Kim, Yong Sik

2011-02-01

Stainless steel is one of the most widely used biomaterials for internal fixation devices, but is not used in cementless arthroplasty implants because a stable oxide layer essential for biocompatibility cannot be formed on the surface. We applied a Ti electron beam coating, to form oxide layer on the stainless steel surface. To form a thicker oxide layer, we used a microarc oxidation process on the surface of Ti coated stainless steel. Modification of the surface using Ti electron beam coating and microarc oxidation could improve the ability of stainless steel implants to osseointegrate. The ability of cells to adhere to grit-blasted, titanium-coated, microarc-oxidated stainless steel in vitro was compared with that of two different types of surface modifications, machined and titanium-coated, and microarc-oxidated. We performed energy-dispersive x-ray spectroscopy and scanning electron microscopy investigations to assess the chemical composition and structure of the stainless steel surfaces and cell morphology. The biologic responses of an osteoblastlike cell line (SaOS-2) were examined by measuring proliferation (cell proliferation assay), differentiation (alkaline phosphatase activity), and attraction ability (cell migration assay). Cell proliferation, alkaline phosphatase activity, migration, and adhesion were increased in the grit-blasted, titanium-coated, microarc-oxidated group compared to the two other groups. Osteoblastlike cells on the grit-blasted, titanium-coated, microarc-oxidated surface were strongly adhered, and proliferated well compared to those on the other surfaces. The surface modifications we used (grit blasting, titanium coating, microarc oxidation) enhanced the biocompatibility (proliferation and migration of osteoblastlike cells) of stainless steel. This process is not unique to stainless steel; it can be applied to many metals to improve their biocompatibility, thus allowing a broad range of materials to be used for cementless implants.

An integrated CAD/CAM/robotic milling method for custom cementless femoral prostheses.

PubMed

Wen-ming, Xi; Ai-min, Wang; Qi, Wu; Chang-hua, Liu; Jian-fei, Zhu; Fang-fang, Xia

2015-09-01

Aseptic loosening is the primary cause of cementless femoral prosthesis failure and is related to the primary stability of the cementless femoral prosthesis in the femoral cavity. The primary stability affects both the osseointegration and the long-term stability of cementless femoral prostheses. A custom cementless femoral prosthesis can improve the fit and fill of the prosthesis in the femoral cavity and decrease the micromotion of the proximal prosthesis such that the primary stability of the custom prosthesis can be improved, and osseointegration of the proximal prosthesis is achieved. These results will help to achieve long-term stability in total hip arthroplasty (THA). In this paper, we introduce an integrated CAD/CAM/robotic method of milling custom cementless femoral prostheses. The 3D reconstruction model uses femoral CT images and 3D design software to design a CAD model of the custom prosthesis. After the transformation matrices between two units of the robotic system are calibrated, consistency between the CAM software and the robotic system can be achieved, and errors in the robotic milling can be limited. According to the CAD model of the custom prosthesis, the positions of the robotic tool points are produced by the CAM software of the CNC machine. The normal vector of the three adjacent robotic tool point positions determines the pose of the robotic tool point. In conclusion, the fit rate of custom pig femur stems in the femoral cavities was 90.84%. After custom femoral prostheses were inserted into the femoral cavities, the maximum gaps between the prostheses and the cavities measured less than 1 mm at the diaphysis and 1.3 mm at the metaphysis. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

Ceramic bearings with bilayer coating in cementless total hip arthroplasty. A safe solution. A retrospective study of one hundred and twenty six cases with more than ten years' follow-up.

PubMed

Ferreira, André; Aslanian, Thierry; Dalin, Thibaud; Picaud, Jean

2017-05-01

Using a ceramic-ceramic bearings, cementless total hip arthroplasty (THA) has provided good clinical results. To ensure longevity a good quality fixation of the implants is mandatory. Different surface treatments had been used, with inconsistent results. We hypothesized that a "bilayer coating" applied to both THA components using validated technology will provide a long-lasting and reliable bone fixation. We studied the survival and bone integration of a continuous, single-surgeon, retrospective series of 126 THA cases (116 patients) with an average follow-up of 12.2 years (minimum 10 years). The THA consisted of cementless implants with a bilayer coating of titanium and hydroxyapatite and used a ceramic-ceramic bearing. With surgical revision for any cause (except infection) as the end point, THA survival was 95.1 % at 13 years. Stem (98.8 %) and cup (98.6 %) survival was similar at 13 years. Bone integration was confirmed in 100 % of implants (Engh-Massin score of 17.42 and ARA score of 5.94). There were no instances of loosening. Revisions were performed because of instability (1.6 %), prosthetic impingement or material-related issues. A bilayer titanium and hydroxyapatite coating provides strong, fast, reliable osseo integration, without deterioration at the interface or release of damaging particles. The good clinical outcomes expected of ceramic bearings were achieved, as were equally reliable stem and cup fixation.

Total Hip Arthroplasty in Haemophilic Patients with Modern Cementless Implants.

PubMed

Carulli, Christian; Felici, Irene; Martini, Caterina; Civinini, Roberto; Linari, Silvia; Castaman, Giancarlo; Innocenti, Massimo

2015-10-01

Hip arthropathy due to recurrent haemarthrosis in patients with haemophilia can be disabling. When severe degeneration occurs, total hip arthroplasty is indicated. Reported outcomes are variable and out of date. The aim of this study is to evaluate the survivorship of Total Hip Arthroplasty performed in a patient population with modern cementless implants. Twenty-three haemophilic patients were treated and followed by a multidisciplinary team dedicated to haemophilia. The mean age was 40.6 years. No failures or complications were recorded at a mean follow-up of 8.1 years (range: 3.1-13.7). A multidisciplinary team and the use of modern cementless implants may represent the keys to achieve good outcomes, fewer complications, and better survivorship in the approach to these difficult cases. Copyright © 2015 Elsevier Inc. All rights reserved.

An initial experience with hip resurfacing versus cementless total hip arthroplasty.

PubMed

Arndt, Justin Michael; Wera, Glenn D; Goldberg, Victor M

2013-07-01

Hip resurfacing is an alternative to total hip arthroplasty. We aimed to compare an experienced hip surgeon's initial clinical results of hip resurfacing with a new cementless total hip arthroplasty (THA). The first 55 consecutive hip resurfacing arthroplasties were compared to 100 consecutive cementless THAs using a cylindrical tapered femoral stem. The learning curve between the two procedures was compared utilizing the incidence of reoperation, complications, Harris Hip Scores (HHS), and implant survivorship. The reoperation rate was significantly higher (p = 0.019) for hip resurfacing (14.5%) versus THA (4%). The overall complication rate between the two groups was not significantly different (p = 0.398). Preoperative HHS were similar between the two groups (p = 0.2). The final mean HHS was similar in both the resurfacing and THA groups (96 vs. 98.3, respectively, p < 0.65). Kaplan-Meier survival analysis with an endpoint of reoperation suggests complications occurred earlier in the resurfacing group versus the THA group (log-rank test, p = 0.007). In comparison to our initial experience with a cementless THA stem, operative complications occur earlier and more often after hip resurfacing during the learning period. The clinical outcomes in both groups however are similar at 5 year follow-up.

To Cement or Not? Two-Year Results of a Prospective, Randomized Study Comparing Cemented Vs. Cementless Total Knee Arthroplasty (TKA).

PubMed

Fricka, Kevin B; Sritulanondha, Supatra; McAsey, Craig J

2015-09-01

The optimal mode of fixation in total knee arthroplasty (TKA) is a subject of debate. We enrolled 100 TKA patients randomized to cemented or cementless fixation. Knee Society Scores (KSS), Oxford scores and pain visual analog scales (VAS) were collected pre-operatively and post-operatively. Two-year follow-up was obtained for 93 patients. The mean VAS trended higher for the cementless group at 4 months (P=0.06). At 2 years, the KSS functional scores, Oxford scores, and self-reported questions for satisfaction, less pain and better function were similar but the cemented group had higher KSS clinical scores (96.4 vs. 92.3, P=0.03). More radiolucencies were seen in cementless knees (P<0.001). The cementless group had one revision for instability and one cemented knee was revised for infection. Cementless TKA showed equivalent survivorship (revision for any reason as the endpoint) compared to cemented TKA at this early follow-up. Close monitoring of radiolucencies is important with continued follow-up. Copyright © 2015 Elsevier Inc. All rights reserved.

31. FORGE, ANVIL, POWER FORGE HAMMER (FRONT TO BACK), AND ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

31. FORGE, ANVIL, POWER FORGE HAMMER (FRONT TO BACK), AND DOORWAY INTO MAIN SHOP-LOOKING SOUTHWEST. - W. A. Young & Sons Foundry & Machine Shop, On Water Street along Monongahela River, Rices Landing, Greene County, PA

Forging Long Shafts On Disks

NASA Technical Reports Server (NTRS)

Tilghman, Chris; Askey, William; Hopkins, Steven

1989-01-01

Isothermal-forging apparatus produces long shafts integral with disks. Equipment based on modification of conventional isothermal-forging equipment, required stroke cut by more than half. Enables forging of shafts as long as 48 in. (122 cm) on typical modified conventional forging press, otherwise limited to making shafts no longer than 18 in. (46cm). Removable punch, in which forged material cools after plastic deformation, essential novel feature of forging apparatus. Technology used to improve such products as components of gas turbines and turbopumps and of other shaft/disk parts for powerplants, drive trains, or static structures.

Cementless Total Knee Arthroplasty in Patients Older Than 75 Years.

PubMed

Newman, Jared M; Khlopas, Anton; Chughtai, Morad; Gwam, Chukwuweike U; Mistry, Jaydev B; Yakubek, George A; Harwin, Steven F; Mont, Michael A

2017-11-01

Some surgeons have been hesitant to use cementless fixation for total knee arthroplasty (TKA) in elderly patients due to concerns regarding successful bone biological fixation. Therefore, this study evaluated: (1) implant survivorship, (2) functional outcomes, (3) radiographic outcomes, and (4) complications in patients over 75 years of age who underwent cementless total knee arthroplasty. A total of 134 patients (142 TKAs) older than 75 years at a single institution between June 2008 and June 2014 were retrospectively reviewed. Their mean follow-up was 4 years (range: 2-8 years). The cohort consisted of 91 women and 43 men who had a mean age of 80 years (range: 76 to 88 years). The preoperative diagnoses were osteoarthritis ( n  = 107 patients), rheumatoid arthritis ( n  = 21 patients), and osteonecrosis ( n  = 6 patients). Descriptive statistics were used to calculate the means and ranges and a Kaplan-Meier analysis was performed to determine the aseptic and all cause implant survivorship. Radiographic evaluation was performed using the new Knee Society Radiographic Evaluation and Scoring System. Functional outcomes at the final follow-up as well as all medical and surgical complications were recorded for each patient. The aseptic implant survivorship was 99.3% (95% CI: 7.9-8.1), and the all cause implant survivorship was 98.6% (95% CI: 7.9-8.1). There was one aseptic revision and one septic revision. At the latest follow-up the mean Knee Society pain score was 93 points (range, 80-100 points), and the mean Knee Society function score was 84 points (range, 70-90 points). On radiographic evaluation, there were no progressive radiolucencies, subsidence, and loosening of prostheses at the latest follow-up. The use of cementless TKA demonstrated excellent survivorship, mid-term clinical and functional outcomes, as well as no progressive radiolucencies or subsidence in patients older than 75 years. In addition, there was a low rate of surgical and medical

Precision forging technology for aluminum alloy

NASA Astrophysics Data System (ADS)

Deng, Lei; Wang, Xinyun; Jin, Junsong; Xia, Juchen

2018-03-01

Aluminum alloy is a preferred metal material for lightweight part manufacturing in aerospace, automobile, and weapon industries due to its good physical properties, such as low density, high specific strength, and good corrosion resistance. However, during forging processes, underfilling, folding, broken streamline, crack, coarse grain, and other macro- or microdefects are easily generated because of the deformation characteristics of aluminum alloys, including narrow forgeable temperature region, fast heat dissipation to dies, strong adhesion, high strain rate sensitivity, and large flow resistance. Thus, it is seriously restricted for the forged part to obtain precision shape and enhanced property. In this paper, progresses in precision forging technologies of aluminum alloy parts were reviewed. Several advanced precision forging technologies have been developed, including closed die forging, isothermal die forging, local loading forging, metal flow forging with relief cavity, auxiliary force or vibration loading, casting-forging hybrid forming, and stamping-forging hybrid forming. High-precision aluminum alloy parts can be realized by controlling the forging processes and parameters or combining precision forging technologies with other forming technologies. The development of these technologies is beneficial to promote the application of aluminum alloys in manufacturing of lightweight parts.

Intraoperative Proximal Femoral Fracture in Primary Cementless Total Hip Arthroplasty.

PubMed

Ponzio, Danielle Y; Shahi, Alisina; Park, Andrew G; Purtill, James J

2015-08-01

Intraoperative proximal femoral fracture is a complication of primary cementless total hip arthroplasty (THA) at rates of 2.95-27.8%. A retrospective review of 2423 consecutive primary cementless THA cases identified 102 hips (96 patients) with fracture. Multivariate analysis compared fracture incidences between implants, Accolade (Stryker Orthopaedics) and Tri-Lock (DePuy Orthopaedics, Inc.), and evaluated potential risk factors using a randomized control group of 1150 cases without fracture. The fracture incidence was 4.4% (102/2423), 3.7% (36/1019) using Accolade and 4.9% using Tri-Lock (66/1404) (P=0.18). Female gender (OR=1.96; 95% CI 1.19-3.23; P=0.008) and smaller stem size (OR=1.64; 95% CI 1.04-2.63; P=0.03) predicted increased odds of fracture. No revisions of the femoral component were required in the fracture cohort. Copyright © 2015 Elsevier Inc. All rights reserved.

Titanium Aluminide Casting Technology Development

NASA Astrophysics Data System (ADS)

Bünck, Matthias; Stoyanov, Todor; Schievenbusch, Jan; Michels, Heiner; Gußfeld, Alexander

2017-12-01

Titanium aluminide alloys have been successfully introduced into civil aircraft engine technology in recent years, and a significant order volume increase is expected in the near future. Due to its beneficial buy-to-fly ratio, investment casting bears the highest potential for cost reduction of all competing production technologies for TiAl-LPTB. However, highest mechanical properties can be achieved by TiAl forging. In view of this, Access e.V. has developed technologies for the production of TiAl investment cast parts and TiAl die cast billets for forging purposes. While these parts meet the highest requirements, establishing series production and further optimizing resource and economic efficiency are present challenges. In order to meet these goals, Access has recently been certified according to aircraft standards, aiming at qualifying parts for production on technology readiness level 6. The present work gives an overview of the phases of development and certification.

Long-term result of cementless femoral stem in avascular necrosis of the hip.

PubMed

Cheung, Kin W; Chiu, Kwok H; Chung, Kwong Y

2015-01-01

Avascular necrosis (AVN) of the hip may have extensive involvement of the proximal femur which may affect boney ingrowth into cementless femoral stems. From 1994 to 2004, 182 total hip arthroplasties (in 144 patients, 117 AVN hips and 65 non-AVN hips) were performed using hydroxyapatite coated femoral stems. All patients were followed up prospectively. Mean age was 51 years and mean follow-up 14.7 years (range 9.7-19.1 years). Four stems were revised because of aseptic loosening, 3 in AVN group and 1 in non-AVN group. The overall mechanical failure rate was 2.2%, the mechanical failure rate in AVN and non-AVN group was 2.6% and 1.5% respectively (p = 1). The 19.1 year survival using revision for aseptic loosening as an endpoint for AVN and non-AVN patients were 97.1% and 96.2% respectively (p = 0.654). Stable boney ingrowth was present in 99.5% hips. This study represents 1 of the largest series reporting the long-term follow-up of the use of cementless femoral stems in treating AVN of the hip. We report excellent long-term survival of cementless total hip arthroplasty used in managing AVN of the hip and is comparable to that seen in non-AVN total hip arthroplasty.

2014 Accomplishments-Tritium aging studies on stainless steel: Fracture toughness properties of forged stainless steels-Effect of hydrogen, forging strain rate, and forging temperature

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morgan, Michael J.

Forged stainless steels are used as the materials of construction for tritium reservoirs. During service, tritium diffuses into the reservoir walls and radioactively decays to helium-3. Tritium and decay helium cause a higher propensity for cracking which could lead to a tritium leak or delayed failure of a tritium reservoir. The factors that affect the tendency for crack formation and propagation include: Environment; steel type and microstructure; and, vessel configuration (geometry, pressure, residual stress). Fracture toughness properties are needed for evaluating the long-term effects of tritium on their structural properties. Until now, these effects have been characterized by measuring themore » effects of tritium on the tensile and fracture toughness properties of specimens fabricated from experimental forgings in the form of forward-extruded cylinders. A key result of those studies is that the long-term cracking resistance of stainless steels in tritium service depends greatly on the interaction between decay helium and the steels’ forged microstructure. New experimental research programs are underway and are designed to measure tritium and decay helium effects on the cracking properties of stainless steels using actual tritium reservoir forgings instead of the experimental forgings of past programs. The properties measured should be more representative of actual reservoir properties because the microstructure of the specimens tested will be more like that of the tritium reservoirs. The programs are designed to measure the effects of key forging variables on tritium compatibility and include three stainless steels, multiple yield strengths, and four different forging processes. The effects on fracture toughness of hydrogen and crack orientation were measured for type 316L forgings. In addition, hydrogen effects on toughness were measured for Type 304L block forgings having two different yield strengths. Finally, fracture toughness properties of type

Deformation processes in forging ceramics

NASA Technical Reports Server (NTRS)

Cannon, R. M.; Rhodes, W. H.

1972-01-01

The deformation processes involved in the forging of refractory ceramic oxides were investigated. A combination of mechanical testing and forging are utilized to investigate both the flow and fracture processes involved. An additional hemisphere forging was done which failed prematurely. Analysis and comparison with available fracture data for AL2O3 indicated possible causes of the failure. Examination of previous forgings indicated an increase in grain boundary cavitation with increasing strain.

Does osteoporosis reduce the primary tilting stability of cementless acetabular cups?

PubMed

von Schulze Pellengahr, Christoph; von Engelhardt, Lars V; Wegener, Bernd; Müller, Peter E; Fottner, Andreas; Weber, Patrick; Ackermann, Ole; Lahner, Matthias; Teske, Wolfram

2015-04-21

Cementless hip cups need sufficient primary tilting stability to achieve osseointegration. The aim of the study was to assess differences of the primary implant stability in osteoporotic bone and in bone with normal bone density. To assess the influence of different cup designs, two types of threaded and two types of press-fit cups were tested. The maximum tilting moment for two different cementless threaded cups and two different cementless press-fit cups was determined in macerated human hip acetabuli with reduced (n=20) and normal bone density (n=20), determined using Q-CT. The tilting moments for each cup were determined five times in the group with reduced bone density and five times in the group with normal bone density, and the respective average values were calculated. The mean maximum extrusion force of the threaded cup Zintra was 5670.5 N (max. tilting moment 141.8 Nm) in bone with normal density and.5748.3 N (max. tilting moment 143.7 Nm) in osteoporotic bone. For the Hofer Imhof (HI) threaded cup it was 7681.5 N (192.0 Nm) in bone with normal density and 6828.9 N (max. tilting moment 170.7 Nm) in the group with osteoporotic bone. The mean maximum extrusion force of the macro-textured press-fit cup Metallsockel CL was 3824.6 N (max. tilting moment 95.6 Nm) in bone with normal and 2246.2 N (max. tilting moment 56.2 Nm) in osteoporotic bone. For the Monoblock it was 1303.8 N (max. tilting moment 32.6 Nm) in normal and 1317 N (max. tilting moment 32.9 Nm) in osteoporotic bone. There was no significance. A reduction of the maximum tilting moment in osteoporotic bone of the ESKA press-fit cup Metallsockel CL was noticed. Results on macerated bone specimens showed no statistically significant reduction of the maximum tilting moment in specimens with osteoporotic bone density compared to normal bone, neither for threaded nor for the press-fit cups. With the limitation that the results were obtained using macerated bone, we could not detect any restrictions for

Bone scans after total knee arthroplasty in asymptomatic patients. Cemented versus cementless

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hofmann, A.A.; Wyatt, R.W.; Daniels, A.U.

1990-02-01

The natural history of bone scans after total knee arthroplasty (TKA) was studied in 26 patients with 28 cemented TKAs and 29 patients with 31 cementless TKAs. The bone scans were examined at specified postoperative intervals. Radionuclide activity of the femoral, tibial, and patellar regions was measured. Six patients who developed pain postoperatively were excluded. Bone scans immediately postoperative and at three months demonstrated increased uptake, which gradually decreased to baseline levels at ten to 12 months. Radioisotope uptake was comparable in the cemented and cementless groups, but was highly variable in individual patients and in each of the follow-upmore » periods. A single postoperative bone scan cannot differentiate component loosening from early bone remodeling. Sequential bone scans, as a supplement to the clinical examination and conventional radiography, may prove useful in the diagnosis of TKA failure.« less

Forging Industry Leadtimes: An Analysis of Causes for and Solutions to Long Leadtimes for Aerospace Forgings

DTIC Science & Technology

1986-09-01

Pamplet . Forging Industry Association, Cleveland-MT, uncatea. 20. Forging Industry Association, and American Society for Metals. Forging Handbook, edited... Pamplet . The Harris-Thomas Drop Forge Compnyayto--n R, undated. 43. Theeck, Michael F., TECH MOD Program Mana.er. Personal interview. Industrial Base... Brochure . Worcester MA, 3, . 125 "’ VITA Captain Stephen F. O’Neill was born on 19 June 1957 in Pittsfield, Massachusetts. He graduated from high school

Results of revision total knee arthroplasty using press-fit cementless stem.

PubMed

Iamaguchi, Maurício Masasi; de Castro, Fernando Bley Vicente; Gobbi, Riccardo Gomes; Tirico, Luis Eduardo Passarelli; Pécora, José Ricardo; Camanho, Gilberto Luis

2013-01-01

To show our experience with press-fit cementless stem and metaphyseal fixation with cement in a selected series of patients who underwent revision total knee arthroplasty. Thirty-four patients (35 knees) underwent revision total knee arthroplasty using the press-fit technique. Minimum follow-up was one year (mean 2.2 years) with a maximum length of three years. Of 34 patients, 20 were women and 14 were men. There was one death due to causes not related to arthroplasty and one patient dropout. There were no cases in which further review was necessary. Patients who underwent revision had clinical and functional improvement demonstrated by the results of the KSS, results of the SF-36 quality of life questionnaire, through gains in range of motion and improved limb alignment. There was postoperative clinical and functional improvement in comparison to the preoperative status in revision total knee arthroplasty with press-fit cementless stem. Level of Evidence IV, Case series.

Cementless Oxford medial unicompartimental knee replacement: an independent series with a 5-year-follow-up.

PubMed

Panzram, Benjamin; Bertlich, Ines; Reiner, Tobias; Walker, Tilman; Hagmann, Sébastien; Gotterbarm, Tobias

2017-07-01

Cemented unicompartmental knee replacement (UKR) has proven excellent long-term survival rates and functional scores in Price et al. (Clin Orthop Relat Res 435:171-180, 2005), Price and Svard (Clin Orthop Relat Res 469(1):174-179, 2011) and Murray et al. (Bone Joint Surg Br 80(6):983-989, 1998). The main causes for revision, aseptic loosening and pain of unknown origin might be addressed by cementless UKR in Liddle et al. (Bone Joint J 95-B(2):181-187, 2013), Pandit et al. (J Bone Joint Surg Am 95(15):1365-1372, 2013), National Joint Registry for England, Wales and Northern Ireland: 10th Annual Report 2013 ( http://www.njrcentre.org.uk/njrcentre/Portals/0/Documents/England/Reports/10th_annual_report/NJR%2010th%20Annual%20Report%202013%20B.pdf , 2013), Swedish Knee Arthroplasty Register: Annual Report 2013 ( http://www.myknee.se/pdf/SKAR2013_Eng.pdf , 2013). This single-centre retrospective cohort study reports the 5-year follow-up results of our first 30 consecutively implanted cementless Oxford UKR (OUKR). Clinical outcome was measured using the OKS, AKSS, range of movement and level of pain (visual analogue scale). The results were compared to cemented OUKR in a matched-pair analysis. Implant survival was 89.7%. One revision each was performed due to tibial fracture, progression of osteoarthritis (OA) and inlay dislocation. The 5-year survival rate of the cementless group was 89.7% and of the cemented group 94.1%. Both groups showed excellent postoperative clinical scores. Cementless fixation shows good survival rates and clinical outcome compared to cemented fixation.

Microstructural and mechanical evolutions during the forging step of the COBAPRESS, a casting/forging process

NASA Astrophysics Data System (ADS)

Perrier, Frédéric; Desrayaud, Christophe; Bouvier, Véronique

Aluminum casting/forging processes are used to produce parts for the automotive industry. In this study, we examined the influence of the forging step on the microstructure and the mechanical properties of an A356 aluminum alloy modified with strontium. Firstly, a design of samples which allows us to test mechanically the alloy before and after forging was created. A finite element analysis with the ABAQUS software predicts a maximum of strain in the core of the specimens. Observations with the EBSD technique confirm a more intense sub-structuration of the dendrite cells in this zone. Yield strength, ultimate tensile strength, elongation and fatigue lives were then improved for the casting/forging samples compared to the only cast specimens. The closure of the porosities and the improvement of the surface quality during the forging step enhance also the fatigue resistance of the samples.

Microstructural Evaluation of Forging Parameters for Superalloy Disks

NASA Technical Reports Server (NTRS)

Falsey, John R.

2004-01-01

Forgings of nickel base superalloy were formed under several different strain rates and forging temperatures. Samples were taken from each forging condition to find the ASTM grain size, and the as large as grain (ALA). The specimens were mounted in bakelite, polished, etched and then optical microscopy was used to determine grain size. The specimens ASTM grain sizes from each forging condition were plotted against strain rate, forging temperature, and presoak time. Grain sizes increased with increasing forging temperature. Grain sizes also increased with decreasing strain rates and increasing forging presoak time. The ALA had been determined from each forging condition using the ASTM standard method. Each ALA was compared with the ASTM grain size of each forging condition to determine if the grain sizes were uniform or not. The forging condition of a strain rate of .03/sec and supersolvus heat treatment produced non uniform grains indicated by critical grain growth. Other anomalies are noted as well.

The Bimetric cementless total hip replacement: 7-18 year follow-up assessing the influence of acetabular design on survivorship.

PubMed

Russell, R C; Ghassemi, A; Dorrell, J H; Powles, D P

2009-08-01

The purpose of this study was to evaluate the mid- to long-term survivorship of Bimetric cementless total hip replacement and assess how it is affected by the acetabular design. This was a retrospective analysis of 127 Bimetric cementless total hip replacements in 110 patients with a follow-up of 7-18 years. A single design stem and three different cementless metal-backed acetabular designs were used. Patients were assessed clinically using the Harris hip score and radiologically by independent review of current hip radiographs. There was only one case of aseptic loosening of the femoral stem. The earliest acetabular design showed a high failure rate whilst the latter two designs showed a 96% survivorship at a mean of 9.5 years. We conclude that a combination of the bimetric stem with either of the latter acetabular cup designs has a good mid- to long-term performance.

48 CFR 225.7102 - Forgings.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Forgings. 225.7102 Section 225.7102 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF... Forgings. ...

Design of forging process variables under uncertainties

NASA Astrophysics Data System (ADS)

Repalle, Jalaja; Grandhi, Ramana V.

2005-02-01

Forging is a complex nonlinear process that is vulnerable to various manufacturing anomalies, such as variations in billet geometry, billet/die temperatures, material properties, and workpiece and forging equipment positional errors. A combination of these uncertainties could induce heavy manufacturing losses through premature die failure, final part geometric distortion, and reduced productivity. Identifying, quantifying, and controlling the uncertainties will reduce variability risk in a manufacturing environment, which will minimize the overall production cost. In this article, various uncertainties that affect the forging process are identified, and their cumulative effect on the forging tool life is evaluated. Because the forging process simulation is time-consuming, a response surface model is used to reduce computation time by establishing a relationship between the process performance and the critical process variables. A robust design methodology is developed by incorporating reliability-based optimization techniques to obtain sound forging components. A case study of an automotive-component forging-process design is presented to demonstrate the applicability of the method.

Have cementless and resurfacing components improved the medium-term results of hip replacement for patients under 60 years of age?

PubMed Central

Mason, James; Baker, Paul; Gregg, Paul J; Porter, Martyn; Deehan, David J; Reed, Mike R

2015-01-01

Background and purpose The optimal hip replacement for young patients remains unknown. We compared patient-reported outcome measures (PROMs), revision risk, and implant costs over a range of hip replacements. Methods We included hip replacements for osteoarthritis in patients under 60 years of age performed between 2003 and 2010 using the commonest brand of cemented, cementless, hybrid, or resurfacing prosthesis (11,622 women and 13,087 men). The reference implant comprised a cemented stem with a conventional polyethylene cemented cup and a standard-sized head (28- or 32-mm). Differences in implant survival were assessed using competing-risks models, adjusted for known prognostic influences. Analysis of covariance was used to assess improvement in PROMs (Oxford hip score (OHS) and EQ5D index) in 2014 linked procedures. Results In males, PROMs and implant survival were similar across all types of implants. In females, revision was statistically significantly higher in hard-bearing and/or small-stem cementless implants (hazard ratio (HR) = 4) and resurfacings (small head sizes (< 48 mm): HR = 6; large head sizes (≥ 48 mm): HR = 5) when compared to the reference cemented implant. In component combinations with equivalent survival, women reported significantly greater improvements in OHS with hybrid implants (22, p = 0.006) and cementless implants (21, p = 0.03) (reference, 18), but similar EQ5D index. For men and women, National Health Service (NHS) costs were lowest with the reference implant and highest with a hard-bearing cementless replacement. Interpretation In young women, hybrids offer a balance of good early functional improvement and low revision risk. Fully cementless and resurfacing components are more costly and do not provide any additional benefit for younger patients. PMID:25285617

Biomechanical evaluation of adjunctive cerclage wire fixation for the prevention of periprosthetic femur fractures using cementless press-fit total hip replacement.

PubMed

Christopher, Scott A; Kim, Stanley E; Roe, Simon; Pozzi, Antonio

2016-08-01

Periprosthetic femoral fractures are a common complication associated with cementless press-fit total hip arthroplasty. The use of prophylactic cerclage wire fixation has been advocated to reduce this complication. The objective of this study was to evaluate whether a double loop cerclage wire, used as adjunctive fixation, increased the peak torsional load to failure in femora implanted with press-fit cementless stems. Peak torsional load to failure was compared between femora without adjunctive fixation and femora receiving a 1 mm double loop cerclage wire placed proximally to the lesser trochanter. Femora treated with adjunctive cerclage wire fixation failed at 20% greater peak torque (P = 0.0001). In conclusion, a double loop cerclage wire may aid in the prevention of periprosthetic fractures associated with press-fit cementless femoral stems. Copyright © 2016. Published by Elsevier Ltd.

Changes of bone mineral density after cementless total hip arthroplasty with two different stems

PubMed Central

Ito, Kouji; Yamamoto, Kengo

2007-01-01

Cementless total hip arthroplasty has achieved reliable long-term results since porous coatings were developed, but postoperative changes around the stem remain poorly documented. In this study, changes of the bone mineral density (BMD) were compared between two types of cementless stem. In group B (28 patients with 31 hips), a straight tapered stem with porous plasma spray coating on the proximal 1/4 was used, while group S (24 patients with 26 hips) was given a fluted, tri-slot stem with porous hydroxyapatite coating on the proximal 1/3. In group B, there was an early decrease of BMD, which recovered after 12 months, indicating that stress shielding was minimal. In group S, however, BMD continued to decrease without recovery. The stem shape and radiological findings suggested that the cause of stress shielding in group S was distal fixation. PMID:17225187

Forging of Advanced Disk Alloy LSHR

NASA Technical Reports Server (NTRS)

Gabb, Timothy P.; Gayda, John; Falsey, John

2005-01-01

The powder metallurgy disk alloy LSHR was designed with a relatively low gamma precipitate solvus temperature and high refractory element content to allow versatile heat treatment processing combined with high tensile, creep and fatigue properties. Grain size can be chiefly controlled through proper selection of solution heat treatment temperatures relative to the gamma precipitate solvus temperature. However, forging process conditions can also significantly influence solution heat treatment-grain size response. Therefore, it is necessary to understand the relationships between forging process conditions and the eventual grain size of solution heat treated material. A series of forging experiments were performed with subsequent subsolvus and supersolvus heat treatments, in search of suitable forging conditions for producing uniform fine grain and coarse grain microstructures. Subsolvus, supersolvus, and combined subsolvus plus supersolvus heat treatments were then applied. Forging and subsequent heat treatment conditions were identified allowing uniform fine and coarse grain microstructures.

Global fit concept in revision hip arthroplasty for cementless press-fit femoral stems.

PubMed

Canovas, F; LeBeguec, P; Batard, J; Gaillard, F; Dagneaux, L

2017-06-01

A revision stem may be required after a femoral extended trochanteric osteotomy (ETO) is made during revision hip arthroplasty. The two main complications of straight cementless femoral stems are subsidence due to inadequate osteointegration and stress-shielding. We will describe an original revision method with ETO that uses a straight cementless stem. The goal of this method was to achieve the most extensive press-fit possible during stem implantation to improve the transmission of stresses to the bone and to prevent reduction in bone density. The intramedullary preparation was done after closure and fixation of the ETO, which allows impaction of the revision stem with metaphyseal and diaphyseal press-fit. We report encouraging results with preservation of periprosthetic bone stock and good osteointegration of these revision stems at the final follow-up. Pronounced sagittal curvature or large bone defects are contraindications for this technique. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Fixation of Trochanteric Fragments in Cementless Bipolar Hemiarthroplasty of Unstable Intertrochanteric Fracture: Cerclage Wiring

PubMed Central

Lee, Young-Kyun; Koo, Kyung-Hoi

2017-01-01

Purpose Bipolar hemiarthroplasty (HA) is an option for the treatment of unstable intertrochanteric fracture in elderly patients. There is a raising concern regarding cable-grip related complications for the fixation of trochanteric fragments. Therefore, the aim of this study was to evaluate outcome of cementless HA with fixation for the trochanteric fragments using monofilament wires in unstable intertrochanteric fracture. Materials and Methods We reviewed 92 cementless bipolar HAs using a grit-blasted long stem design for unstable intertrochanteric fractures in 91 elderly patients with a mean age of 81.7 years. During the arthroplasty, trochanteric fracture fragments were fixed using 1 or 2 vertical wires and transverse wires. We evaluated the clinical outcomes such as abductor power, ambulatory ability and wire-related complications, and radiologic outcomes including the union of the trochanteric fragment and subsidence of stem. Results Sixty-two patients were followed for a minimum of 2 years (mean, 59 months) postoperatively. The mean abductor power and Koval category was 4.1 (range, 3 to 5) and 4.6 (range, 1 to 6). The wire was broken in 3 hips (4.8%) and the nonunion of the greater trochanter occurred in 1 hips (1.6%). Two stems subsided by 3 mm and 8 mm, respectively, during postoperative 6 weeks, after which the subsidence was not progressive. Conclusion Cerclage wiring of the trochanter using monofilament wire leads to acceptable outcome in cementless HA for senile patients with unstable intertrochanteric fracture. Cerclage wiring using a monofilament wire is recommended for the fixation of trochanteric fragments. PMID:29250501

Early Migration Predicts Aseptic Loosening of Cementless Femoral Stems: A Long-term Study.

PubMed

Streit, Marcus R; Haeussler, Daniel; Bruckner, Thomas; Proctor, Tanja; Innmann, Moritz M; Merle, Christian; Gotterbarm, Tobias; Weiss, Stefan

2016-07-01

Excessive early migration of cemented stems and cups after THA has been associated with poor long-term survival and allows predictable evaluation of implant performance. However, there are few data regarding the relationship between early migration and aseptic loosening of cementless femoral components, and whether early migration might predict late failure has not been evaluated, to our knowledge. Einzel-Bild-Röntgen-Analyse-femoral component analysis (EBRA-FCA) is a validated technique to accurately measure axial femoral stem migration without the need for tantalum markers, can be performed retrospectively, and may be a suitable tool to identify poor performing implants before their widespread use. We asked: (1) Is axial migration within the first 24 months as assessed by EBRA-FCA greater among cementless stems that develop aseptic loosening than those that remain well fixed through the second decade; (2) what is the diagnostic performance of implant migration at 24 months postoperatively to predict later aseptic loosening of these components; and (3) how does long-term stem survivorship compare between groups with high and low early migration? We evaluated early axial stem migration in 158 cementless THAs using EBRA-FCA. The EBRA-FCA measurements were performed during the first week postoperatively (baseline measurement) and at regular followups of 3, 6, and 12 months postoperatively and annually thereafter. The mean duration of followup was 21 years (range, 18-24 years). The stems studied represented 45% (158 of 354) of the cementless THAs performed during that time, and cementless THAs represented 34% (354 of 1038) of the THA practice during that period. No patient enrolled in this study was lost to followup. Multivariate survivorship analysis using Cox's regression model was performed with an endpoint of aseptic loosening of the femoral component. Loosening was defined according to the criteria described by Engh et al. and assessed by two independent

The Bimetric cementless total hip replacement: 7–18 year follow-up assessing the influence of acetabular design on survivorship

PubMed Central

Ghassemi, A.; Dorrell, J. H.; Powles, D. P.

2008-01-01

The purpose of this study was to evaluate the mid- to long-term survivorship of Bimetric cementless total hip replacement and assess how it is affected by the acetabular design. This was a retrospective analysis of 127 Bimetric cementless total hip replacements in 110 patients with a follow-up of 7–18 years. A single design stem and three different cementless metal-backed acetabular designs were used. Patients were assessed clinically using the Harris hip score and radiologically by independent review of current hip radiographs. There was only one case of aseptic loosening of the femoral stem. The earliest acetabular design showed a high failure rate whilst the latter two designs showed a 96% survivorship at a mean of 9.5 years. We conclude that a combination of the bimetric stem with either of the latter acetabular cup designs has a good mid- to long-term performance. PMID:18551293

Cementless fixation of "isoelastic" hip endoprostheses manufactured from plastic materials.

PubMed

Morscher, E W; Dick, W

1983-06-01

Nine years of clinical experience with an "isoelastic" shaft prosthesis manufactured using polyacetal resin reveal that for the transmission of forces from the pelvis through the femoral head and neck into the femoral shaft, some rigidity of the proximal part of the prosthesis is necessary. The object is to eliminate micromovements, which lead to bone resorption and implant loosening. However, elasticity greater than that present in metallic implants prevents stress concentrations and disuse stress protection atrophy of the bone. Greater elasticity of the prosthesis, which can be achieved by plastic materials, makes possible a more even, harmonious distribution of the forces transmitted from the implant to the bone and vice versa. A more elastic implant can also act as a better shock absorber than a rigid one. The results in 627 cementless polyethylene cups after a maximum observation period of 5.5 years reveal good incorporation and no aseptic loosening. Especially favorable results occurred in 61 cases by replacing loosened cemented cups with bone grafts and cementless polyethylene cups. On the femoral shaft side too high an elasticity in the proximal part of the prosthesis led to bone resorption and loosening with the first model of the prosthesis. By reinforcing the proximal part of the femoral component, much better results were obtained. The isoelastic femoral shaft, however, is in an early stage of experimentation.

Hot forging of roll-cast high aluminum content magnesium alloys

NASA Astrophysics Data System (ADS)

Kishi, Tomohiro; Watari, Hisaki; Suzuki, Mayumi; Haga, Toshio

2017-10-01

This paper reports on hot forging of high aluminum content magnesium alloy sheets manufactured using horizontal twin-roll casting. AZ111 and AZ131 were applied for twin-roll casting, and a hot-forging test was performed to manufacture high-strength magnesium alloy components economically. For twin-roll casting, the casting conditions of a thick sheet for hot forging were investigated. It was found that twin-roll casting of a 10mm-thick magnesium alloy sheet was possible at a roll speed of 2.5m/min. The grain size of the cast strip was 50 to 70µm. In the hot-forging test, blank material was obtained from as-cast strip. A servo press machine with a servo die cushion was used to investigate appropriate forging conditions (e.g., temperature, forging load, and back pressure) for twin-roll casts (TRCs) AZ111 and AZ131. It was determined that high aluminum content magnesium alloy sheets manufactured using twin-roll casting could be forged with a forging load of 150t and a back pressure of 3t at 420 to 430°C. Applying back pressure during hot forging effectively forged a pin-shaped product.

Osseointegration into a Novel Titanium Foam Implant in the Distal Femur of a Rabbit

PubMed Central

Willie, Bettina M.; Yang, Xu; Kelly, Natalie H.; Merkow, Justin; Gagne, Shawn; Ware, Robin; Wright, Timothy M.; Bostrom, Mathias P.G.

2010-01-01

A novel porous titanium foam implant has recently been developed to enhance biological fixation of orthopaedic implants to bone. The aim of this study was to examine the mechanical and histological characteristics of bone apposition into two different pore sizes of this titanium foam (565 and 464 micron mean void intercept length) and to compare these characteristics to those obtained with a fully porous conventionally sintered titanium bead implant. Cylindrical implants were studied in a rabbit distal femoral intramedullary osseointegration model at time zero and at 3, 6, and 12 weeks. The amount of bone ingrowth, amount of periprosthetic bone, and mineral apposition rate of periprosthetic bone measured did not differ among the three implant designs at 3, 6, or 12 weeks. By 12 weeks, the interface stiffness and maximum load of the beaded implant was significantly greater than either foam implant. No significant difference was found in the interface stiffness or maximum load between the two foam implant designs at 3, 6, or 12 weeks. The lower compressive modulus of the foam compared to the more dense sintered beaded implants likely contributed to the difference in failure mode. However, the foam implants have a similar compressive modulus to other clinically successful coatings, suggesting they are nonetheless clinically adequate. Additional studies are required to confirm this in weight-bearing models. Histological data suggest that these novel titanium foam implants are a promising alternative to current porous coatings and should be further investigated for clinical application in cementless joint replacement. PMID:20024964

Press forging and optical properties of lithium fluoride

NASA Astrophysics Data System (ADS)

Ready, J. F.; Vora, H.

1980-07-01

Lithium fluoride is an important candidate material for windows on high power, short-pulse ultraviolet and visible lasers. Lithium fluoride crystals were press forged in one step over the temperature range 300 to 600 C to obtain fine grained polycrystalline material with improved mechanical properties. The deformation that can be given to a lithium fluoride crystal during forging is limited by the formation of internal cloudiness (veiling) with the deformation limit increasing with increasing forging temperature from about 40 percent at 400 C to 65 percent at 600 C. To suppress veiling, lithium fluoride crystals were forged in two steps over the temperature range 300 to 600 C, to total deformations of 69 to 76 percent, with intermediate annealing at 700 C. This technique yields a material which has lower scattering with more homogeneous microstructure than that obtained in one step forging. The results of characterization of various optical and mechanical properties of single crystal and forged lithium fluoride, including scattering, optical homogeneity, residual absorption, damage thresholds, environmental stability, and thresholds for microyield are described.

Total knee replacement-cementless tibial fixation with screws: 10-year results.

PubMed

Ersan, Önder; Öztürk, Alper; Çatma, Mehmet Faruk; Ünlü, Serhan; Akdoğan, Mutlu; Ateş, Yalım

2017-12-01

The aim of this study was to evaluate the long term clinical and radiological results of cementless total knee replacement. A total of 51 knees of 49 patients (33 female and 16 male; mean age: 61.6 years (range, 29-66 years)) who underwent TKR surgery with a posterior stabilized hydroxyapatite coated knee implant were included in this study. All of the tibial components were fixed with screws. The HSS scores were examined preoperatively and at the final follow-up. Radiological assessment was performed with Knee Society evaluating and scoring system. Kaplan-Meier survival analysis was performed to rule out the survival of the tibial component. The mean HSS scores were 45.8 (range 38-60) and 88.1 (range 61-93), preoperatively and at the final follow-up respectively. Complete radiological assessment was performed for 48 knees. Lucent lines at the tibial component were observed in 4 patients; one of these patients underwent a revision surgery due to the loosening of the tibial component. The 10-year survival rate of a tibial component was 98%. Cementless total knee replacement has satisfactory long term clinical results. Primary fixation of the tibial component with screws provides adequate stability even in elderly patients with good bone quality. Level IV, Therapeutic study. Copyright © 2017 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

Co-Operative Training in the Sheffield Forging Industry

ERIC Educational Resources Information Center

Duncan, R.

2008-01-01

Purpose: The purpose of this paper is to give details of an operation carried out in Sheffield to increase the recruitment of young men into the steel forging industry. Design/methodology/approach: The Sheffield Forges Co-operative Training Scheme was designed to encourage boys to enter the forging industry and to provide them with training and…

Stainless-steel elbows formed by spin forging

NASA Technical Reports Server (NTRS)

1964-01-01

Large seamless austenitic stainless steel elbows are fabricated by spin forging /rotary shear forming/. A specially designed spin forging tool for mounting on a hydrospin machine has been built for this purpose.

Functionalized coatings by cold spray: An in vitro study of micro- and nanocrystalline hydroxyapatite compared to porous titanium.

PubMed

Vilardell, A M; Cinca, N; Garcia-Giralt, N; Dosta, S; Cano, I G; Nogués, X; Guilemany, J M

2018-06-01

Three different surface treatments on a Ti6Al4V alloy have been in vitro tested for possible application in cementless joint prosthesis. All of them involve the novelty of using the Cold Spray technology for their deposition: (i) an as-sprayed highly rough titanium and, followed by the deposition of a thin hydroxyapatite layer with (ii) microcrystalline or (iii) nanocrystalline structure. Primary human osteoblasts were extracted from knee and seeded onto the three different surfaces. Cell viability was tested by MTS and LIVE/DEAD assays, cell differentiation by alkaline phosphatase (ALP) quantification and cell morphology by Phalloidin staining. All tests were carried out at 1, 7 and 14 days of cell culture. Different cell morphologies between titanium and hydroxyapatite surfaces were exhibited. At 1 day of cell culture, cells on the titanium coating were spread and flattened, expanding the filopodia actin filaments in all directions, while cells on the hydroxyapatite coatings showed round like-shape morphology due to slower attachment. Higher cell viability was detected at all times of cell culture on titanium coating due to a better attachment at 1 day. However, from 7 days of cell culture, cells on hydroxyapatite showed good attachment onto surfaces and highly increased their proliferation, mostly on nanocrystalline, achieving similar cell viability levels than titanium coatings. ALP levels were significantly higher in titanium, in part, because of greatest cell number. Overall, the best cell functional results were obtained on titanium coatings whereas microcrystalline hydroxyapatite presented the worst cellular parameters. However, results indicate that nanocrystalline hydroxyapatite coatings may achieve promising results for the faster cell proliferation once cells are attached on the surface. Copyright © 2018 Elsevier B.V. All rights reserved.

Bipolar Hemarthroplasty Using Cementless Conical Stem for Treatment of Dorr Type B and C Femoral Neck Fracture.

PubMed

Kang, Jeong Hoon; Lee, Sang Hong; Jung, Sung

2015-12-01

The current study aims to evaluate the clinical and the radiological outcome of bipolar hemiarthroplasty using cementless cone stem to treat osteoporotic femoral neck fracture and compare the results according to the proximal femur geometry. Seventy-five hips (75 patients) that underwent bipolar hemiarthroplasty with cementless cone stem between September 2006 and December 2011 were analyzed. The minimum follow-up period was 3 years. Thirty-three hips were classified as type B and 41 as type C. The clinical outcome was assessed using Harris hip score and the walking ability score. Radiographic evaluation was performed to evaluate the stability of the prosthesis. At the most recent follow up, the mean Harris hip score was 86 (range, 70-92) and 65% recovered to preoperative ambulatory status. In the radiographic exam, stable stem fixation was achieved in all cases. For the complications, eight hips developed deep vein thrombosis while three hips showed heterotopic ossification. Dislocation and delayed deep infection occurred in one hip resepectively. There were no significance differences in Harris hip score and walking ability score when the type B group was compare with the type C. Bipolar hemiarthroplasty with cementless cone stem showed an excellent early outcome both clinically and radiographically regardless of the shape of the proximal femur. We believe this prosthesis can provide early stability to the Dorr type B and C femur and is an effective treatment for treating osteoporotic femoral neck fracture.

Reactor pressure vessel with forged nozzles

DOEpatents

Desai, Dilip R.

1993-01-01

Inlet nozzles for a gravity-driven cooling system (GDCS) are forged with a cylindrical reactor pressure vessel (RPV) section to which a support skirt for the RPV is attached. The forging provides enhanced RPV integrity around the nozzle and substantial reduction of in-service inspection costs by eliminating GDCS nozzle-to-RPV welds.

22 CFR 121.10 - Forgings, castings and machined bodies.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Forgings, castings and machined bodies. 121.10... STATES MUNITIONS LIST Enumeration of Articles § 121.10 Forgings, castings and machined bodies. Articles on the U.S. Munitions List include articles in a partially completed state (such as forgings...

Sustained load crack growth design data for Ti-6Al-4V titanium alloy tanks containing hydrazine

NASA Technical Reports Server (NTRS)

Lewis, J. C.; Kenny, J. T.

1976-01-01

Sustained load crack growth data for Ti-6Al-4V titanium alloy in hydrazine per MIL-P-26536 and refined hydrazine are presented. Fracture mechanics data on crack growth thresholds for heat-treated forgings, aged and unaged welds, and aged and unaged heat-affected zones are reported. Fracture mechanics design curves of crack growth threshold stress intensity versus temperature are generated from 40 to 71 C.

A Short Study of Large Rotary Forged Cylinders

DTIC Science & Technology

1979-06-01

ESR Steel Hollow ESR Steel Rotary Forge Vacuum Degassed Steel 20. ABSTRACT (Continue on reverse aide It necessary and identity by block number...treatment rging Line was used to produce steel for the Advanced ocram. Cylinders were rotary forged from cast hollow ESR ssed steel . Anomalies in the data...prompted a more detailed The results are presented. Satisfactory properties were cuum degassed steel . However, the very light forging th the very

Near-Net Forging Technology Demonstration Program

NASA Technical Reports Server (NTRS)

Hall, I. Keith

1996-01-01

Significant advantages in specific mechanical properties, when compared to conventional aluminum (Al) alloys, make aluminum-lithium (Al-Li) alloys attractive candidate materials for use in cryogenic propellant tanks and dry bay structures. However, the cost of Al-Li alloys is typically five times that of 2219 aluminum. If conventional fabrication processes are employed to fabricate launch vehicle structure, the material costs will restrict their utilization. In order to fully exploit the potential cost and performance benefits of Al-Li alloys, it is necessary that near-net manufacturing methods be developed to off-set or reduce raw material costs. Near-net forging is an advanced manufacturing method that uses elevated temperature metal movement (forging) to fabricate a single piece, near-net shape, structure. This process is termed 'near-net' because only a minimal amount of post-forge machining is required. The near-net forging process was developed to reduce the material scrap rate (buy-to-fly ratio) and fabrication costs associated with conventional manufacturing methods. The goal for the near-net forging process, when mature, is to achieve an overall cost reduction of approximately 50 percent compared with conventional manufacturing options for producing structures fabricated from Al-Li alloys. This NASA Marshall Space Flight Center (MSFC) sponsored program has been a part of a unique government / industry partnership, coordinated to develop and demonstrate near-net forging technology. The objective of this program was to demonstrate scale-up of the near-net forging process. This objective was successfully achieved by fabricating four integrally stiffened, 170- inch diameter by 20-inch tall, Al-Li alloy 2195, Y-ring adapters. Initially, two 2195 Al-Li ingots were converted and back extruded to produce four cylindrical blockers. Conventional ring rolling of the blockers was performed to produce ring preforms, which were then contour ring rolled to produce

27 CFR 447.22 - Forgings, castings, and machined bodies.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 3 2010-04-01 2010-04-01 false Forgings, castings, and... IMPLEMENTS OF WAR The U.S. Munitions Import List § 447.22 Forgings, castings, and machined bodies. Articles on the U.S. Munitions Import List include articles in a partially completed state (such as forgings...

Flaw Growth of 6Al-4V Titanium in a Freon TF Environment

NASA Technical Reports Server (NTRS)

Tiffany, C. F.; Masters, J. N.; Bixler, W. D.

1969-01-01

The plane strain threshold stress intensity and sustained stress flaw growth rates were experimentally determined for 6AI-4V S.T.A. titanium forging and weldments in environments of Freon TF at room temperature. Sustained load tests of surface flawed specimens were conducted with the experimental approach based on linear elastic fracture mechanics. It was concluded that sustained stress flaw growth rates, in conjunction with threshold stress intensities, can be used in assessing the service life of pressure vessels.

Complications of porous-coated press-fit cementless total hip replacement in dogs.

PubMed

Kidd, Scott W; Preston, Christopher A; Moore, George E

2016-09-20

To report postoperative complications using a commercially available porous-coated press-fit cementless total hip replacement (THR) system in dogs. Medical records were reviewed for client-owned dogs with hip pathologies requiring THR. A minimum of six-week postoperative orthopaedic examination and orthogonal pelvic radiographs were used to assess outcome and complications in the perioperative period. Referring veterinarian medical records, phone interviews with clients, or both were used to assess long-term functional outcome and complications. Bilateral THR was performed in 36 dogs, and unilateral in 147 dogs, making a total of 219 THR procedures in 183 dogs. A total complication rate of 31.1% (68/219) was observed. A catastrophic complication was observed in 8.2% (n = 18), a major complication in 9.6% (n = 21), and a minor complication in 13.2% (n = 29) of procedures. The most common complications were intra-operative femoral fissure (n = 46), diaphyseal femoral fracture (n = 15), and coxofemoral luxation (n = 9). Full return to function was achieved in 88.1% of procedures with a median follow-up period of 42 months. Porous-coated press-fit cementless collarless total hip replacements have a high complication rate. The majority of complications occur intra-operatively or perioperatively, with few complications occurring beyond 12 weeks postoperatively. Both fissure fractures and diaphyseal femoral fractures carry a favourable prognosis with immediate cerclage wiring and plate fixation, respectively.

Cementless Tapered Wedge Femoral Stems Decrease Subsidence in Obese Patients Compared to Traditional Fit-and-Fill Stems.

PubMed

Grant, Tanner W; Lovro, Luke R; Licini, David J; Warth, Lucian C; Ziemba-Davis, Mary; Meneghini, Robert M

2017-03-01

Femoral component stability and resistance to subsidence is critical for osseointegration and clinical success in cementless total hip arthroplasty. The purpose of this study was to radiographically evaluate the anatomic fit and subsidence of 2 different proximally tapered, porous-coated modern cementless femoral component designs. A retrospective cohort study of 126 consecutive cementless total hip arthroplasties was performed. Traditional fit-and-fill stems were implanted in the first 61 hips with the remaining 65 receiving morphometric tapered wedge stems. Preoperative bone morphology was radiographically assessed by the canal flare index. Canal fill in the coronal plane, subsidence, and the sagittal alignment of stems was measured digitally on immediate and 1-month postoperative radiographs. Demographics and canal flare indices were similar between groups. The percentage of femoral canal fill was greater in the tapered wedge compared to the fit-and-fill stem (P = .001). There was significantly less subsidence in the tapered wedge design (0.3 mm) compared to the fit-and-fill design (1.1 mm) (P = .001). Subsidence significantly increased as body mass index (BMI) increased in the fit-and-fill stems, a finding not observed in the tapered wedge design (P = .013). An anatomically designed morphometric tapered wedge femoral stem demonstrated greater axial stability and decreased subsidence with increasing BMI than a traditional fit-and-fill stem. The resistance to subsidence, irrespective of BMI, is likely due to the inherent axial stability of a tapered wedge design and may be the optimal stem design for obese patients. Copyright © 2016 Elsevier Inc. All rights reserved.

40 CFR 467.40 - Applicability; description of the forging subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... forging subcategory. 467.40 Section 467.40 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ALUMINUM FORMING POINT SOURCE CATEGORY Forging Subcategory § 467.40 Applicability; description of the forging subcategory. This subpart applies to discharges of...

Utah FORGE Site Earthquake Animation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Joe Moore

This is a .kml earthquake animation covering the period of 1991 - 2011 for the Utah Milford FORGE site. It displays seismic events using different sized bubbles according to magnitude. It covers the general Utah FORGE area (large shaded rectangle) with the final site displayed as a smaller polygon along the northwestern margin. Earthquakes are subdivide into clusters and the time, date, and magnitude of each event is included. Nearby seismic stations are symbolized with triangles. This was created by the University of Utah Seismograph Stations (UUSS).

Carbon/PEEK composite materials as an alternative for stainless steel/titanium hip prosthesis: a finite element study.

PubMed

Rezaei, Farshid; Hassani, Kamran; Solhjoei, Nosratollah; Karimi, Alireza

2015-12-01

Total hip replacement (THR) has been ranked within the most typical surgical processes in the world. The durability of the prosthesis and loosening of prosthesis are the main concerns that mostly reported after THR surgeries. In THR, the femoral prosthesis can be fixed by either cement or cementless methods in the patient's bones. In both procedures, the stability of the prosthesis in the hosted bone has a key asset in its long-term durability and performance. This study aimed to execute a comparative finite element simulation to assess the load transfer between the prosthesis, which is made of carbon/PEEK composite and stainless steel/titanium, and the femur bone. The mechanical behavior of the cortical bone was assumed as a linear transverse isotropic while the spongy bone was modeled like a linear isotropic material. The implants were made of stainless steel (316L) and titanium alloy as they are common materials for implants. The results showed that the carbon/PEEK composites provide a flatter load transfer from the upper body to the leg compared to the stainless steel/titanium prosthesis. Furthermore, the results showed that the von Mises stress, principal stress, and the strain in the carbon/PEEK composites prosthesis were significantly lower than that made of the stainless steel/titanium. The results also imply that the carbon/PEEK composites can be applied to introduce a new optimum design for femoral prosthesis with adjustable stiffness, which can decrease the stress shielding and interface stress. These findings will help clinicians and biomedical experts to increase their knowledge about the hip replacement.

48 CFR 252.225-7025 - Restriction on acquisition of forgings.

Code of Federal Regulations, 2010 CFR

2010-10-01

... of forgings. 252.225-7025 Section 252.225-7025 Federal Acquisition Regulations System DEFENSE... CLAUSES Text of Provisions And Clauses 252.225-7025 Restriction on acquisition of forgings. As prescribed in 225.7102-4, use the following clause: Restriction on Acquisition of Forgings (DEC 2009) (a...

Deformation, recrystallization, strength, and fracture of press-forged ceramic crystals.

NASA Technical Reports Server (NTRS)

Rice, R. W.

1972-01-01

Sapphire and ruby were very difficult to press-forge because they deformed without cracking only in a limited temperature range before they melted. Spinel crystals were somewhat easier and MgO, CaO, and TiC crystals much easier to forge. The degree of recrystallization that occurred during forging (which was related to the ease and type of slip intersections) varied from essentially zero in Al2O3 to complete (i.e., random polycrystalline bodies were produced) in CaO. Forging of bi- and polycrystalline bodies produced incoherent bodies as a result of grain-boundary sliding. Strengths of the forged crystals were comparable to those of dense polycrystalline bodies of similar grain size. However, forged and recrystallized CaO crystals were ductile at lower temperatures than dense hot-pressed CaO. This behavior is attributed to reduced grain-boundary impurities and porosity. Fracture origins could be located, indicating that fracture in the CaO occurs internally as a result of surface work hardening caused by machining.-

3D Finite Element Analysis of Spider Non-isothermal Forging Process

NASA Astrophysics Data System (ADS)

Niu, Ling; Wei, Wei; Wei, Kun Xia; Alexandrov, Igor V.; Hu, Jing

2016-06-01

The differences of effective stress, effective strain, velocity field, and the load-time curves between the spider isothermal and non-isothermal forging processes are investigated by making full use of 3D FEA, and verified by the production experiment of spider forging. Effective stress is mainly concentrated on the pin, and becomes lower closer to the front of the pin. The maximum effective strain in the non-isothermal forging is lower than that in the isothermal. The great majority of strain in the non-isothermal forging process is 1.76, which is larger than the strain of 1.31 in the isothermal forging. The maximum load required in the isothermal forging is higher than that in the non-isothermal. The maximum experimental load and deformation temperature in the spider production are in good agreement with those in the non-isothermal FEA. The results indicate that the non-isothermal 3D FEA results can guide the design of the spider forging process.

The Anatomy of AP1000 Mono-Block Low Pressure Rotor Forging

NASA Astrophysics Data System (ADS)

Jin, Jia-yu; Rui, Shou-tai; Wang, Qun

AP1000 mono-block low pressure (LP) rotor forgings for nuclear power station have maximum ingot weight, maximum diameter and the highest technical requirements. It confronts many technical problems during manufacturing process such as composition segregation and control of inclusion in the large ingot, core compaction during forging, control of grain size and mechanical performance. The rotor forging were anatomized to evaluate the manufacturing level of CFHI. This article introduces the anatomical results of this forging. The contents include chemical composition, mechanical properties, inclusions and grain size and other aspects from the full-length and full cross-section of this forging. The fluctuation of mechanical properties, uniformity of microstructure and purity of chemical composition were emphasized. The results show that the overall performance of this rotor forging is particularly satisfying.

Residual Stresses in 21-6-9 Stainless Steel Warm Forgings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Everhart, Wesley A.; Lee, Jordan D.; Broecker, Daniel J.

Forging residual stresses are detrimental to the production and performance of derived machined parts due to machining distortions, corrosion drivers and fatigue crack drivers. Residual strains in a 21-6-9 stainless steel warm High Energy Rate Forging (HERF) were measured via neutron diffraction. The finite element analysis (FEA) method was used to predict the residual stresses that occur during forging and water quenching. The experimentally measured residual strains were used to calibrate simulations of the three-dimensional residual stress state of the forging. ABAQUS simulation tools predicted residual strains that tend to match with experimental results when varying yield strength is considered.

Long-term results with the Atlas IIIp elastic cementless acetabular component in total hip replacement.

PubMed

Lee, Paul Yuh Feng; Rachala, Madhu; Teoh, Kar Ho; Woodnutt, David John

2016-09-01

Modular cementless elastic acetabular systems have advantages over cemented and hard shell cementless acetabular systems. There are few reports on the medium-term and long-term follow up of this particular type of implant. This study describes our experience with the Atlas IIIp modular acetabular system, which is a thin shell cementless elastic acetabular implant for total hip replacement commercialized under this name in many countries. We prospectively followed 244 patients treated with Atlas IIIp acetabular system between 2001 and 2004. Minimum ten year follow up was available for 148 hips (139 patients) from the original cohort of 263 hips (244 patients). One hundred five patients had died from unrelated causes and were excluded from the results. Post-operative and follow up radiographs of patients were assessed; and Harris hip scores were used as clinical outcome. Revision for any reason was defined as the end point for survivorship analysis. The mean pre-operative Harris hip score was 48 (S.D. 16) and the average post-operative score was 82 (S.D. 12). The mean follow up in our series was 11.5 years, ranging from ten to 13.5 years. Thirteen hips required further surgery in our cohort; of which ten cases required cup revision. The 13-years cumulative implant survival was 91.2 % and the risk of implant revision was 8.8 % at 13 years in 148 hips (139 patients). Kaplan-Meier analysis showed the implant survival rate of 95.2 % at ten years for revision for any reason and 99.4 % for aseptic loosening. Our clinical experience with this acetabular cup suggests good long-term survival rates that are similar to other cups on the market. The clinical experience in this study shows long-term survival rates that are consistent, acceptable and good results achieved with a low revision rate. Therapeutic III; therapeutic study.

22 CFR 121.10 - Forgings, castings, and machined bodies.

Code of Federal Regulations, 2014 CFR

2014-04-01

... STATES MUNITIONS LIST Enumeration of Articles § 121.10 Forgings, castings, and machined bodies. The U.S. Munitions List controls as defense articles those forgings, castings, and other unfinished products, such as...

Optimum Design of Forging Process Parameters and Preform Shape under Uncertainties

NASA Astrophysics Data System (ADS)

Repalle, Jalaja; Grandhi, Ramana V.

2004-06-01

Forging is a highly complex non-linear process that is vulnerable to various uncertainties, such as variations in billet geometry, die temperature, material properties, workpiece and forging equipment positional errors and process parameters. A combination of these uncertainties could induce heavy manufacturing losses through premature die failure, final part geometric distortion and production risk. Identifying the sources of uncertainties, quantifying and controlling them will reduce risk in the manufacturing environment, which will minimize the overall cost of production. In this paper, various uncertainties that affect forging tool life and preform design are identified, and their cumulative effect on the forging process is evaluated. Since the forging process simulation is computationally intensive, the response surface approach is used to reduce time by establishing a relationship between the system performance and the critical process design parameters. Variability in system performance due to randomness in the parameters is computed by applying Monte Carlo Simulations (MCS) on generated Response Surface Models (RSM). Finally, a Robust Methodology is developed to optimize forging process parameters and preform shape. The developed method is demonstrated by applying it to an axisymmetric H-cross section disk forging to improve the product quality and robustness.

Nuclear valve manufacturer selects stainless forgings

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

1976-02-01

Forged type 316 stainless steel components for nuclear valves are described. Automatic plasma arc welding with powder filler alloys is employed for hardfacing. Seat ring forgings are surfaced four-at-a-time with Stellite No. 156 in a sequential manner to minimize heat input to the individual components. After cladding and machining, seat rings are welded into the valve body using a semiautomatic, hot-wire gas tungsten-arc process. Disc faces and guide slots are surfaced with Stellite No. 6. The valve stem is machined from 17-4PH forged bar stock in the H-1100 condition. The heat treatment is specified to minimize pitting under prolonged exposuremore » to wet packing. A 12 rms (0.3 $mu$m) surface finish minimizes tearing of the packing and subsequent leakage. The link and stem pin are SA 564 Grade 660 (in the H-1100 condition) and ASTM A637 Grade 718 respectively. (JRD)« less

Roosevelt Hot Springs, Utah FORGE Earthquake Catalog

DOE Data Explorer

Pankow, Kris

2018-03-21

This is the set of earthquake catalogs developed for the Utah FORGE project. These are discussed in the "Utah FORGE Phase 2B Final Topical Report", which can be found on GDR under id: 1038 (See link 'Final Topical Report' in resources below). The details are in section: 'TASK 2B.12: SEISMIC MONITORING PHASE2B FINAL REPORT.' The catalogs are in an Excel file.

The influence of strain rate and the effect of friction on the forging load in simple upsetting and closed die forging

NASA Astrophysics Data System (ADS)

Klemz, Francis B.

Forging provides an elegant solution to the problem of producing complicated shapes from heated metal. This study attempts to relate some of the important parameters involved when considering, simple upsetting, closed die forging and extrusion forging.A literature survey showed some of the empirical graphical and statistical methods of load prediction together with analytical methods of estimating load and energy. Investigations of the effects of high strain rate and temperature on the stress-strain properties of materials are also evident.In the present study special equipment including an experimental drop hammer and various die-sets have been designed and manufactured. Instrumentation to measure load/time and displacement/time behaviour, of the deformed metal, has been incorporated and calibrated. A high speed camera was used to record the behaviour mode of test pieces used in the simple upsetting tests.Dynamic and quasi-static material properties for the test materials, lead and aluminium alloy, were measured using the drop-hammer and a compression-test machine.Analytically two separate mathematical solutions have been developed: A numerical technique using a lumped-massmodel for the analysis of simple upsetting and closed-die forging and, for extrusion forging, an analysis which equates the shear and compression energy requirements tothe work done by the forging load.Cylindrical test pieces were used for all the experiments and both dry and lubricated test conditions were investigated. The static and dynamic tests provide data on Load, Energy and the Profile of the deformed billet. In addition for the Extrusion Forging, both single ended and double ended tests were conducted. Material dependency was also examined by a further series of tests on aluminium and copper.Comparison of the experimental and theoretical results was made which shows clearly the effects of friction and high strain rate on load and energy requirements and the deformation mode of the

Fatigue Life Variability in Large Aluminum Forgings with Residual Stress

DTIC Science & Technology

2011-07-01

been conducted. A detailed finite element analysis of the forge/ quench /coldwork/machine process was performed in order to predict the bulk residual...forge/ quench /coldwork/machine process was performed in order to predict the bulk residual stresses in a fictitious aluminum bulkhead. The residual...continues to develop the capability for computational simulation of the forge, quench , cold work and machining processes. In order to handle the

Optical Forging of Graphene into Three-Dimensional Shapes.

PubMed

Johansson, Andreas; Myllyperkiö, Pasi; Koskinen, Pekka; Aumanen, Jukka; Koivistoinen, Juha; Tsai, Hung-Chieh; Chen, Chia-Hao; Chang, Lo-Yueh; Hiltunen, Vesa-Matti; Manninen, Jyrki J; Woon, Wei Yen; Pettersson, Mika

2017-10-11

Atomically thin materials, such as graphene, are the ultimate building blocks for nanoscale devices. But although their synthesis and handling today are routine, all efforts thus far have been restricted to flat natural geometries, since the means to control their three-dimensional (3D) morphology has remained elusive. Here we show that, just as a blacksmith uses a hammer to forge a metal sheet into 3D shapes, a pulsed laser beam can forge a graphene sheet into controlled 3D shapes in the nanoscale. The forging mechanism is based on laser-induced local expansion of graphene, as confirmed by computer simulations using thin sheet elasticity theory.

Bone density and functional results after femoral revision with a cementless press-fit stem.

PubMed

Canovas, F; Roche, O; Girard, J; Bonnomet, F; Goldschild, M; Le Béguec, P

2015-05-01

The influence of radiographic bone density changes in the area surrounding a total hip arthroplasty (THA) revision with a cementless press-fit stem is unknown, notably in terms of functional results. We have therefore conducted a study aiming to (1) propose a radiographic method to assess bone density, (2) measure the functional effects of reduced bone density, and (3) determine the factors contributing to these modifications. A reduction in radiographic bone density has a negative influence on the functional result after revision using a cementless press-fit stem. We retrospectively assessed 150 THA revisions at a mean follow-up of 6.3 ± 3.2 years (range, 2-15 years). The clinical assessment was based on the Harris Hip Score. Bone density modifications were measured radiographically and the method was evaluated. The change in bone density was classified into two groups: (1) bone density not reduced or < 2 Gruen zones (118 cases [79%]); (2) bone density reduced ≥ 2 zones (32 cases [21%]). The variables showing a potential influence were the Cortical Index (CI), the type of primary stability with the press-fit system, and the femoral implant length. Inter- and intraobserver reliability of radiographic bone density measurement was evaluated as moderate or good (Kappa, 0.58; 0.60 and 0.67, respectively). For the Harris Hip Score at follow-up, there was a borderline statistical relation between stages 1 and 2: for the 118 stage 1 patients, this score was 83.62 ± 11.54 (range, 27-99) versus 78.34 ± 15.98 (range, 62-91) for stage 2 patients (P = 0.09). A CI ≤ 0.44 showed mediocre bone quality contributing to decreased bone density (P < 0.02). On the other hand, there was no statistically significant relation with the type of primary fixation (P = 0.34) or the length of the implant (P = 0.23). A cementless revision femoral stem can induce a reduction in bone density with possible functional effects. The negative role played by bone scarcity on the functional score

Development of high purity large forgings for nuclear power plants

NASA Astrophysics Data System (ADS)

Tanaka, Yasuhiko; Sato, Ikuo

2011-10-01

The recent increase in the size of energy plants has been supported by the development of manufacturing technology for high purity large forgings for the key components of the plant. To assure the reliability and performance of the large forgings, refining technology to make high purity steels, casting technology for gigantic ingots, forging technology to homogenize the material and consolidate porosity are essential, together with the required heat treatment and machining technologies. To meet these needs, the double degassing method to reduce impurities, multi-pouring methods to cast the gigantic ingots, vacuum carbon deoxidization, the warm forging process and related technologies have been developed and further improved. Furthermore, melting facilities including vacuum induction melting and electro slag re-melting furnaces have been installed. By using these technologies and equipment, large forgings have been manufactured and shipped to customers. These technologies have also been applied to the manufacture of austenitic steel vessel components of the fast breeder reactors and components for fusion experiments.

Development of Oxide Dispersion Strengthened (ODS) Ferritic Steel Through Powder Forging

NASA Astrophysics Data System (ADS)

Kumar, Deepak; Prakash, Ujjwal; Dabhade, Vikram V.; Laha, K.; Sakthivel, T.

2017-04-01

Oxide dispersion strengthened (ODS) ferritic steels are candidates for cladding tubes in fast breeder nuclear reactors. In this study, an 18%Cr ODS ferritic steel was prepared through powder forging route. Elemental powders with a nominal composition of Fe-18Cr-2 W-0.2Ti (composition in wt.%) with 0 and 0.35% yttria were prepared by mechanical alloying in a Simoloyer attritor under argon atmosphere. The alloyed powders were heated in a mild steel can to 1473 K under flowing hydrogen atmosphere. The can was then hot forged. Steps of sealing, degassing and evacuation are eliminated by using powder forging. Heating ODS powder in hydrogen atmosphere ensures good bonding between alloy powders. A dense ODS alloy with an attractive combination of strength and ductility was obtained after re-forging. On testing at 973 K, a loss in ductility was observed in yttria-containing alloy. The strength and ductility increased with increase in strain rate at 973 K. Reasons for this are discussed. The ODS alloy exhibited a recrystallized microstructure which is difficult to achieve by extrusion. No prior particle boundaries were observed after forging. The forged compacts exhibited isotropic mechanical properties. It is suggested that powder forging may offer several advantages over the traditional extrusion/HIP routes for fabrication of ODS alloys.

TC17 titanium alloy laser melting deposition repair process and properties

NASA Astrophysics Data System (ADS)

Liu, Qi; Wang, Yudai; Zheng, Hang; Tang, Kang; Li, Huaixue; Gong, Shuili

2016-08-01

Due to the high manufacturing cost of titanium compressor blisks, aero engine repairing process research has important engineering significance and economic value. TC17 titanium alloy is a rich β stable element dual α+β phase alloy whose nominal composition is Ti-5Al-2Sn-2Zr-4Mo-4Cr. It has high mechanical strength, good fracture toughness, high hardenability and a wide forging-temperature range. Through a surface response experiment with different laser powers, scanning speeds and powder feeding speeds, the coaxial powder feeding laser melting deposition repair process is studied for the surface circular groove defects. In this paper, the tensile properties, relative density, microhardness, elemental composition, internal defects and microstructure of the laser-repaired TC17 forging plate are analyzed. The results show that the laser melting deposition process could realize the form restoration of groove defect; tensile strength and elongation could reach 1100 MPa and 10%, which could reach 91-98% that of original TC17 wrought material; with the optimal parameters (1000 W-25 V-8 mm/s), the microhardness of the additive zone, the heat-affected zone and base material is evenly distributed at 370-390 HV500. The element content difference between the additive zone and base material is less than ±0.15%. Due to the existence of the pores 10 μm in diameter, the relative density could reach 99%, which is mainly inversely proportional to the powder feeding speed. The repaired zone is typically columnar and dendrite crystal, and the 0.5-1.5 mm-deep heat-affected zone in the groove interface is coarse equiaxial crystal.

[Technology of cementless hip endoprosthetics].

PubMed

Ungethüm, M; Blömer, W

1987-06-01

The success achieved with non-cemented hip arthroplasty depends mainly on the stability of the fixation, the quality of the stabilizing bone being just as important as favourable biomechanical conditions. The results of the intensive research and development with respect to the particular features of a non-cemented hip endoprosthesis can be divided into the following basic categories: Biomechanical aspects with special reference to bone related to the design of the prosthesis; material characteristics, such as fatigue strength, tribology, corrosion resistance, and biocompatibility; and development of new materials and coatings to permit direct bonding of implant and bone. With regard to the stem of hip prostheses, the different design parameters of various types are examined to determine their typical design characteristics, such as bearing surface of the collar, geometry of cross section, anatomically adapted shaping, and surface of the implant forming the contact with the bone. The latter can be divided into macroprofiles and macro- and micro-porous coated surfaces. On the other hand, the methods of cementless fixation of acetabular cups can be primarily divided into conical and spherical screw fixation and pegged fixation with additional macroprofiles of porous surfaces. In a separate study of the biomechanical aspects of screwed sockets, the special importance of socket shape and thread geometry are presented with reference to primary stability and long-term fixation of prostheses.

Intra-operative evaluation of cementless hip implant stability: a prototype device based on vibration analysis.

PubMed

Lannocca, Maurizio; Varini, Elena; Cappello, Angelo; Cristofolini, Luca; Bialoblocka, Ewa

2007-10-01

Cementless implants are mechanically stabilized during surgery by a press-fitting procedure. Good initial stability is crucial to avoid stem loosening and bone cracking, therefore, the surgeon must achieve optimal press-fitting. A possible approach to solve this problem and assist the surgeon in achieving the optimal compromise, involves the use of vibration analysis. The present study aimed to design and test a prototype device able to evaluate the primary mechanical stability of a cementless prosthesis, based on vibration analysis. In particular, the goal was to discriminate between stable and quasi-stable implants; thus the stem-bone system was assumed to be linear in both cases. For that reason, it was decided to study the frequency responses of the system, instead of the harmonic distortion. The prototype developed consists of a piezoelectric exciter connected to the stem and an accelerometer attached to the femur. Preliminary tests were performed on four composite femurs implanted with a conventional stem. The results showed that the input signal was repeatable and the output could be recorded accurately. The most sensitive parameter to stability was the shift in resonance frequency of the stem-bone system, which was highly correlated with residual micromotion on all four specimens.

Prospective long-term follow-up of the cementless bicontact hip stem with plasmapore coating.

PubMed

Ochs, U; Eingartner, C; Volkmann, R; Ochs, B G; Huber, C; Weller, S; Weise, K

2007-01-01

A prospective long-term study of the first 250 cementless Bicontact stems implanted in the BG Trauma Centre, Tuebingen, Germany. All of the patients in this series (treatment period June 1987 to April 1990) who were still contactable were invited for clinical and radiological follow-up. The radiographs were analysed for signs of loosening in the form of Gruen lysis zones, stress shielding, subsidence behaviour, heterotopic ossification and spot welds. The average follow-up period was 17.8 (16.7 - 19.5) years. The overall rate of follow-up was 65 % (162 of 250) and 91 % of patients who were still alive (162 of 179). The average patient age was 56.2 years at the time of operation and 74.0 years at follow-up. The average HHS was 81.6 points. In the course of the first 10 years (up to 03/1998), a total of 8 stem revisions had to be performed. In the period from 03/1998 to 01/2007, 2 cases of loosening requiring revision occurred in the patients still alive at the time of follow-up. The survival rate calculated was thus 95.6 %. These outstanding results provide enduring support for the philosophy of the cementless and bone-preserving fixation principles underlying the Bicontact hip stem with proximal intertrochanteric transmission of forces and high primary rotational stability.

A Multicenter Approach Evaluating the Impact of Vitamin E-Blended Polyethylene in Cementless Total Hip Replacement

PubMed Central

Jäger, Marcus; van Wasen, Andrea; Warwas, Sebastian; Landgraeber, Stefan; Haversath, Marcel; Group, VITAS

2014-01-01

Since polyethylene is one of the most frequently used biomaterials as a liner in total hip arthroplasty, strong efforts have been made to improve design and material properties over the last 50 years. Antioxidants seems to be a promising alternative to further increase durability and reduce polyethylene wear in long term. As of yet, only in vitro results are available. While they are promising, there is yet no clinical evidence that the new material shows these advantages in vivo. To answer the question if vitamin-E enhanced ultra-high molecular weight polyethylene (UHMWPE) is able to improve long-term survivorship of cementless total hip arthroplasty we initiated a randomized long-term multicenter trial. Designed as a superiority study, the oxidation index assessed in retrieval analyses of explanted liners was chosen as primary parameter. Radiographic results (wear rate, osteolysis, radiolucency) and functional outcome (Harris Hip Scores, University of California-Los Angeles, Hip Disability and Osteoarthritis Outcome Score, Visual Analogue Scale) will serve as secondary parameters. Patients with the indication for a cementless total hip arthroplasty will be asked to participate in the study and will be randomized to either receive a standard hip replacement with a highly cross-linked UHMWPE-X liner or a highly cross-linked vitamin-E supplemented UHMWPE-XE liner. The follow-up will be 15 years, with evaluation after 5, 10 and 15 years. The controlled randomized study has been designed to determine if Vitamin-E supplemented highly cross-linked polyethylene liners are superior to standard XLPE liners in cementless total hip arthroplasty. While several studies have been started to evaluate the influence of vitamin-E, most of them evaluate wear rates and functional results. The approach used for this multicenter study, to analyze the oxidation status of retrieved implants, should make it possible to directly evaluate the ageing process and development of the implant

Roosevelt Hot Springs, Utah FORGE Regional Well Locations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nash, Greg

This archive contains a GIS point feature shapefile that shows the locations of wells in the general region of the Utah FORGE project, near Roosevelt Hot Springs. This includes Utah FORGE deep well 58-32 and wells for which data has been uploaded to the Geothermal Data Repository. The attribute table has a field that contains well names.

Optimising mechanical properties of hot forged nickel superalloy 625 components

NASA Astrophysics Data System (ADS)

Singo, Nthambe; Coles, John; Rosochowska, Malgorzata; Lalvani, Himanshu; Hernandez, Jose; Ion, William

2018-05-01

Hot forging and subsequent heat treatment were resulting in substandard mechanical properties of nickel superalloy, Alloy 625, components. The low strength was found to be due to inadequate deformation during forging, excessive grain growth and precipitation of carbides during subsequent heat treatment. Experimentation in a drop forging company and heat treatment facility led to the establishment of optimal parameters to minimise grain size and mitigate the adverse effects of carbide precipitation, leading to successful fulfilment of mechanical property specifications. This was achieved by reducing the number of operations, maximising the extent of deformation by changing the slug dimensions and its orientation in the die, and minimising the time of exposure to elevated temperatures in both the forging and subsequent heat treatment processes to avoid grain growth.

Comparison of the risk of revision in cementless total hip arthroplasty with ceramic-on-ceramic and metal-on-polyethylene bearings

PubMed Central

Varnum, Claus; Pedersen, Alma B; Kjærsgaard-Andersen, Per; Overgaard, Søren

2015-01-01

Background and purpose Ceramic-on-ceramic (CoC) bearings were introduced in total hip arthroplasty (THA) to reduce problems related to polyethylene wear. We compared the 9-year revision risk for cementless CoC THA and for cementless metal-on-polyethylene (MoP) THA. Patients and methods In this prospective, population-based study from the Danish Hip Arthroplasty Registry, we identified all the primary cementless THAs that had been performed from 2002 through 2009 (n = 25,656). Of these, 1,773 THAs with CoC bearings and 9,323 THAs with MoP bearings were included in the study. To estimate the relative risk (RR) of revision, we used regression with the pseudo-value approach and treated death as a competing risk. Results 444 revisions were identified: 4.0% for CoC THA (71 of 1,773) and 4.0% for MoP THA (373 of 9,323). No statistically significant difference in the risk of revision for any reason was found for CoC and MoP bearings after 9 years of follow-up (adjusted RR = 1.3, 95% CI: 0.72–2.4). Revision rates due to component failure were 0.5% (n = 8) for CoC bearings and 0.1% (n = 6) for MoP bearings (p < 0.001). 6 patients with CoC bearings (0.34%) underwent revision due to ceramic fracture. Interpretation When compared to the “standard” MoP bearings, CoC THA had a 33% higher (though not statistically significantly higher) risk of revision for any reason at 9 years. PMID:25637339

The tridimensional geometry of the proximal femur should determine the design of cementless femoral stem in total hip arthroplasty.

PubMed

Wegrzyn, Julien; Roux, Jean-Paul; Loriau, Charlotte; Bonin, Nicolas; Pibarot, Vincent

2018-02-22

Using a cementless femoral stem in total hip arthroplasty (THA), optimal filling of the proximal femoral metaphyseal volume (PFMV) and restoration of the extramedullary proximal femoral (PF) parameters (i.e., femoral offset (FO), neck length (FNL), and head height (FHH)) constitute key goals for optimal hip biomechanics, functional outcome, and THA survivorship. However, almost 30% of mismatch between the PF anatomy and implant geometry of the most widely implanted non-modular cementless femoral stem has been demonstrated in a computed tomography scan (CT scan) study. Therefore, this anatomic study aimed to evaluate the relationship between the intra- and extramedullary PF parameters using tridimensional CT scan reconstructions. One hundred fifty-one CT scans of adult healthy hips were obtained from 151 male Caucasian patients (mean age = 66 ± 11 years) undergoing lower limb CT scan arteriography. Tridimensional PF reconstructions and parameter measurements were performed using a corrected PF coronal plane-defined by the femoral neck and diaphyseal canal longitudinal axes-to avoid influence of PF helitorsion and femoral neck version on extramedullary PF parameters. Independently of the femoral neck-shaft angle, the PFMV was significantly and positively correlated with the FO, FNL, and FHH (r = 0.407 to 0.420; p < 0.0001). This study emphasized that the tridimensional PF geometry measurement in the corrected coronal plane of the femoral neck can be useful to determine and optimize the design of a non-modular cementless femoral stem. Particularly, continuous homothetic size progression of the intra- and extramedullary PF parameters should be achieved to assure stem fixation and restore anatomic hip biomechanics.

Statistical analysis of interfacial gap in a cementless stem FE model.

PubMed

Park, Youngbae; Choi, Donok; Hwang, Deuk Soo; Yoon, Yong-San

2009-02-01

In cementless total hip arthroplasty, a fair amount of interfacial gap exists between the femoral stem and the bone. However, the effect of these gaps on the mechanical stability of the stem is poorly understood. In this paper, a finite element model with various interfacial gap definitions is used to quantify the effect of interfacial gaps on the primary stability of a Versys Fiber Metal Taper stem under stair climbing loads. In the first part, 500 random interfacial gap definitions were simulated. The resulting micromotion was approximately inversely proportional to the contact ratio, and the variance of the micromotion was greater with a lower contact ratio. Moreover, when the magnitude of the micromotion was compared between the gap definitions that had contact at a specific site and those that had no contact at that site, it was found that gaps located in the proximal-medial region of the stem surface had the most important effect on the micromotion. In a second trial, 17 gap definitions mimicking a gap pattern that has been observed experimentally were simulated. For a given contact ratio, the micromotion observed in the second trial was lower than the average result of those in the first, where the gaps were placed randomly. In either trial, when the contact ratio was higher than 40%, the micromotion showed no significant difference (first trial) or a gentle slope (-0.24 mum% in the second trial) in relation to the contact ratio. Considering the reported contact ratios for properly implanted stems, variations in the amount of interfacial gap would not likely cause a drastic difference in micromotion, and this effect could be easily overshadowed by other clinical factors. In conclusion, differences in interfacial gaps are not expected to have a noticeable effect on the clinical micromotion of this cementless stem.

Using of material-technological modelling for designing production of closed die forgings

NASA Astrophysics Data System (ADS)

Ibrahim, K.; Vorel, I.; Jeníček, Š.; Káňa, J.; Aišman, D.; Kotěšovec, V.

2017-02-01

Production of forgings is a complex and demanding process which consists of a number of forging operations and, in many cases, includes post-forge heat treatment. An optimized manufacturing line is a prerequisite for obtaining prime-quality products which in turn are essential to profitable operation of a forging company. Problems may, however, arise from modifications to the manufacturing route due to changing customer needs. As a result, the production may have to be suspended temporarily to enable changeover and optimization. Using material-technological modelling, the required modifications can be tested and optimized under laboratory conditions outside the plant without disrupting the production. Thanks to material-technological modelling, the process parameters can be varied rapidly in response to changes in market requirements. Outcomes of the modelling runs include optimum parameters for the forging part’s manufacturing route, values of mechanical properties, and results of microstructure analysis. This article describes the use of material-technological modelling for exploring the impact of the amount of deformation and the rate of cooling of a particular forged part from the finish-forging temperature on its microstructure and related mechanical properties.

Combined stamping-forging for non-axisymmetric product

NASA Astrophysics Data System (ADS)

Taureza, Muhammad; Danno, Atsushi; Song, Xu; Oh, Jin An

2016-10-01

Successive combined stamping-forging (CSF) is proposed to produce multi-thickness non-axisymmetric components. This method involves successive compression to create exclusively outward metal flow. Hitherto, the development of CSF has been mostly done for axisymmetric geometry. Using this technique, defect-free rectangular case component with length to thickness ratio of 40 is produced with lower forging pressure. This technology has potential for high throughput production of parts with multiple thicknesses and high width to thickness ratio.

76 FR 50755 - Heavy Forged Hand Tools From China

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-16

... INTERNATIONAL TRADE COMMISSION [Investigation Nos. 731-TA-457-A-D (Third Review)] Heavy Forged... heavy forged hand tools from China would be likely to lead to continuation or recurrence of material.... The views of the Commission are contained in USITC Publication 4250 (August 2011), entitled Heavy...

The development and production of thermo-mechanically forged tool steel spur gears

NASA Technical Reports Server (NTRS)

Bamberger, E. N.

1973-01-01

A development program to establish the feasibility and applicability of high energy rate forging procedures to tool steel spur gears was performed. Included in the study were relatively standard forging procedures as well as a thermo-mechanical process termed ausforming. The subject gear configuration utilized was essentially a standard spur gear having 28 teeth, a pitch diameter of 3.5 inches and a diametral pitch of 8. Initially it had been planned to use a high contact ratio gear design, however, a comprehensive evaluation indicated that severe forging problems would be encountered as a result of the extremely small teeth required by this type of design. The forging studies were successful in achieving gear blanks having integrally formed teeth using both standard and thermo-mechanical forging procedures.

Increased risk of revision of cementless stemmed total hip arthroplasty with metal-on-metal bearings

PubMed Central

Pedersen, Alma B; Mäkelä, Keijo; Eskelinen, Antti; Havelin, Leif Ivar; Furnes, Ove; Kärrholm, Johan; Garellick, Göran; Overgaard, Søren

2015-01-01

Background and purpose Data from the national joint registries in Australia and England and Wales have revealed inferior medium-term survivorship for metal-on-metal (MoM) total hip arthroplasty (THA) than for metal-on-polyethylene (MoP) THA. Based on data from the Nordic Arthroplasty Register Association (NARA), we compared the revision risk of cementless stemmed THA with MoM and MoP bearings and we also compared MoM THA to each other. Patients and methods We identified 32,678 patients who were operated from 2002 through 2010 with cementless stemmed THA with either MoM bearings (11,567 patients, 35%) or MoP bearings (21,111 patients, 65%). The patients were followed until revision, death, emigration, or the end of the study period (December 31, 2011), and median follow-up was 3.6 (interquartile range (IQR): 2.4–4.8) years for MoM bearings and 3.4 (IQR: 2.0–5.8) years for MoP bearings. Multivariable regression in the presence of competing risk of death was used to assess the relative risk (RR) of revision for any reason (with 95% confidence interval (CI)). Results The cumulative incidence of revision at 8 years of follow-up was 7.0% (CI: 6.0–8.1) for MoM bearings and 5.1% (CI: 4.7–5.6) for MoP bearings. At 6 years of follow-up, the RR of revision for any reason was 1.5 (CI: 1.3–1.7) for MoM bearings compared to MoP bearings. The RR of revision for any reason was higher for the ASR (adjusted RR = 6.4, CI: 5.0–8.1), the Conserve Plus (adjusted RR = 1.7, CI: 1.1–2.5) and “other” acetabular components (adjusted RR = 2.4, CI: 1.5–3.9) than for MoP THA at 6 years of follow-up. Interpretation At medium-term follow-up, the survivorship for cementless stemmed MoM THA was inferior to that for MoP THA, and metal-related problems may cause higher revision rates for MoM bearings with longer follow-up. PMID:25715878

Construction of a test bench for closed die forging

NASA Astrophysics Data System (ADS)

Batit, G.; Kaczmarek, B.; Ravassard, P.

1984-03-01

A swan neck press was equipped with hydraulic jacks to enable it to press and forge complex shapes in closed dies in one operation without wasting metal. Maximum closing stress is 250 kN, maximum pressing stress is 250 kN, maximum forging stress is 70 kN.

22 CFR 121.10 - Forgings, castings and machined bodies.

Code of Federal Regulations, 2013 CFR

2013-04-01

... STATES MUNITIONS LIST Enumeration of Articles § 121.10 Forgings, castings and machined bodies. Articles on the U.S. Munitions List include articles in a partially completed state (such as forgings... identifiable as defense articles. If the end-item is an article on the U.S. Munitions List (including...

22 CFR 121.10 - Forgings, castings and machined bodies.

Code of Federal Regulations, 2011 CFR

2011-04-01

... STATES MUNITIONS LIST Enumeration of Articles § 121.10 Forgings, castings and machined bodies. Articles on the U.S. Munitions List include articles in a partially completed state (such as forgings... identifiable as defense articles. If the end-item is an article on the U.S. Munitions List (including...

22 CFR 121.10 - Forgings, castings and machined bodies.

Code of Federal Regulations, 2012 CFR

2012-04-01

... STATES MUNITIONS LIST Enumeration of Articles § 121.10 Forgings, castings and machined bodies. Articles on the U.S. Munitions List include articles in a partially completed state (such as forgings... identifiable as defense articles. If the end-item is an article on the U.S. Munitions List (including...

High incidence of intraoperative calcar fractures with the cementless CLS Spotorno stem.

PubMed

Timmer, Carla; Gerhardt, Davey M J M; de Visser, Enrico; de Kleuver, Marinus; van Susante, Job L C

2018-05-07

This study reports on the incidence of intraoperative calcar fractures with the cementless Spotorno (CLS) stem, and the potential role of a learning curve and implant positioning is investigated. After introduction of the CLS stem, 800 consecutive cementless total hip arthroplasties (THA) were analyzed. The incidence of calcar fracture in the first 400 THA was compared with the second 400 THA, in order to study a potential learning curve effect. According to the instruction for users, varus positioning of the stem was avoided and a femoral neck osteotomy was aimed relatively close to the lesser trochanter since these are assumed to be correlated with calcar fractures. Implant positioning (neck-shaft angle, femoral offset and osteotomy-lesser trochanter distance) was measured on postoperative pelvic radiographs of all THA with calcar fractures and 100 randomly selected uncomplicated control cases. Seventeen (2.1%) intraoperative calcar fractures were recorded. The incidence of calcar fracture differed between the first 400 THA (n = 11) and the second 400 THA (n = 6). This difference was not statistically significant (p = 0.220); however, these numbers indicate a trend toward a learning effect. No significant difference in stem positioning nor the height of the femoral neck osteotomy was measured between THA with a calcar fracture (n = 17) and the control cases (n = 100). We report on a high incidence of intraoperative calcar fractures with the use of a CLS stem. The risk for calcar fractures remains clinically significant even after adequate implant positioning in the hands of experienced hip surgeons. Surgeons should be aware of this implant related phenomenon and be alert on this phenomenon intraoperatively.

Outcome after cementless total hip arthroplasty for arthritic hip in patients with residual poliomyelitis: a case series.

PubMed

Cho, Yoon J; Lee, Choong H; Chun, Young S; Rhyu, Kee H

2016-09-29

In this case series, we investigated the outcome of cementless total hip arthroplasty (THA) for advanced hip osteoarthritis in patients with residual poliomyelitis to evaluate its clinical usefulness for these patients. 11 unilateral cementless primary THA were performed to arthritic hips in patients with residual poliomyelitis. 7 were in paralytic and 4 were in nonparalytic limbs. The mean follow-up duration was 79.9 months. Retrospective clinical evaluations with various scores and radiological evaluations were made. Harris Hip Score, Western Ontario and McMaster Universities Arthritis Index (WOMAC) and Short-form (SF)-36 physical scales were significantly improved after the surgery. However, UCLA activity score and SF-36 mental scale were not. Because of remaining leg length discrepancies, all but 1 noted a residual limp. In nonparalytic hip, functional acetabular cup inclination during weight bearing significantly increased from installed inclination. Other than 1 case of posterior dislocation, no complications were observed. Although the overall result itself is excellent, THA for these patients cannot improve limp, physical activity and mental status. Surgeons should be aware of the change of the inclination of acetabular cup during mobilisation, especially for THA in contralateral hip.

The cost analysis of cemented versus cementless total hip replacement operations on the NHS.

PubMed

Kallala, R; Anderson, P; Morris, S; Haddad, F S

2013-07-01

In a time of limited resources, the debate continues over which types of hip prosthesis are clinically superior and more cost-effective. Orthopaedic surgeons increasingly need robust economic evidence to understand the full value of the operation, and to aid decision making on the 'package' of procedures that are available and to justify their practice beyond traditional clinical preference. In this paper we explore the current economic debate about the merits of cemented and cementless total hip replacement, an issue that continues to divide the orthopaedic community.

JPRS Report, Science & Technology, Japan

DTIC Science & Technology

1991-01-31

final test. Keywords: Spherical Pressure Hull, Titanium Alloy , Three-Dimensional Machining, Electron Beam Welding . 1. Introduction In bodies like... processed (the heat treatment involving high-temperature heating and rapid quenching in order to obtain finer grains of the titanium alloy ) and...given m Table 3. The test results were all satisfactory. Forged material of titanium alloy , manufactured by forging, beta processing , and billet

Efficacy and safety of the topical application of tranexamic acid in primary cementless hip arthroplasty: prospective, randomised, double-blind and controlled study.

PubMed

Tavares Sánchez-Monge, F J; Aguado Maestro, I; Bañuelos Díaz, A; Martín Ferrero, M Á; García Alonso, M F

To evaluate the efficacy of topical tranexamic acid topical in cementless total hip arthroplasty from the point of view of bleeding, transfusion requirements and length of stay, and describe the complications of use compared to a control group. A prospective, randomised, double-blinded and controlled study including all patients undergoing cementless total hip arthroplasty in our centre between June 2014 and July 2015. Blood loss was estimated using the formula described by Nadler and Good. The final analysis included 119 patients. The decrease in haemoglobin after surgery was lower in the tranexamic acid group (3.28±1.13g/dL) than in the controls (4.03±1.27g/dL, P=.001) and estimated blood loss (1,216.75±410.46mL vs. 1,542.12±498.97mL, P<.001), the percentage of transfused patients (35.9% vs. 19.3%, P<.05) and the number of transfused red blood cell units per patient (0.37±0.77 vs. 0.98±1.77; P<.05). There were no differences between groups in the occurrence of complications or length of stay. The use of topical tranexamic acid in cementless total hip arthroplasty results in a decrease in bleeding and transfusion requirements without increasing the incidence of complications. Copyright © 2017 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.

Strength computation of forged parts taking into account strain hardening and damage

NASA Astrophysics Data System (ADS)

Cristescu, Michel L.

2004-06-01

Modern non-linear simulation software, such as FORGE 3 (registered trade mark of TRANSVALOR), are able to compute the residual stresses, the strain hardening and the damage during the forging process. A thermally dependent elasto-visco-plastic law is used to simulate the behavior of the material of the hot forged piece. A modified Lemaitre law coupled with elasticiy, plasticity and thermic is used to simulate the damage. After the simulation of the different steps of the forging process, the part is cooled and then virtually machined, in order to obtain the finished part. An elastic computation is then performed to equilibrate the residual stresses, so that we obtain the true geometry of the finished part after machining. The response of the part to the loadings it will sustain during it's life is then computed, taking into account the residual stresses, the strain hardening and the damage that occur during forging. This process is illustrated by the forging, virtual machining and stress analysis of an aluminium wheel hub.

Experimental pre-clinical assessment of the primary stability of two cementless femoral knee components.

PubMed

Berahmani, Sanaz; Hendriks, Maartje; Wolfson, David; Wright, Abraham; Janssen, Dennis; Verdonschot, Nico

2017-11-01

To achieve long-lasting fixation of cementless implants, an adequate primary stability is required. We aimed to compare primary stability of a new cementless femoral knee component (Attune®) against a conventional implant (LCS®) under different loading conditions. Six pairs of femora were prepared following the normal surgical procedure. Calibrated CT-scans and 3D-optical scans of the bones were obtained to measure bone mineral density (BMD) and cut accuracy, respectively. Micromotions were measured in nine regions of interest at the bone-implant interface using digital image correlation. The reconstructions were subjected to the implant-specific's peak tibiofemoral load of gait and a deep knee bend loading profiles. Afterwards, the implants were pushed-off at a flexion angle of 150°. Micromotions of Attune were significantly lower than LCS under both loading conditions (P ≤ 0.001). Cut accuracy did not affect micromotions, and BMD was only a significant factor affecting the micromotions under simplified gait loading. No significant difference was found in high-flex push-off force, but Attune required a significantly higher load to generate excessive micromotions during push-off. Parallel anterior and posterior bone cuts in the LCS versus the tapered bone cuts of the Attune may explain the difference between the two designs. Additionally, the rims at the borders of the LCS likely reduced the area of contact with the bone for the LCS, which may have affected the initial fixation. Copyright © 2017 Elsevier Ltd. All rights reserved.

10-year evaluation of the cementless low-contact- stress rotating-platform total knee arthroplasty.

PubMed

Efstathopoulos, Nikolaos; Mavrogenis, Andreas F; Lallos, Stergios; Nikolaou, Vassilios; Papagelopoulos, Panayiotis J; Savvidou, Olga D; Korres, Demetrios S

2009-01-01

We present the clinical and radiographic outcomes of the cementless low-contact-stress (LCS) rotating-platform total knee arthroplasty. Overall, 423 prostheses were implanted in 393 consecutive patients (30 patients had bilateral total knee replacement) for primary varus gonarthrosis (381 patients) and rheumatoid arthritis (12 patients). There were 81 men and 312 women with a mean age of 73 years (range, 58-85 years). Patella replacement was not performed in any case. Clinical and radiographic evaluation was performed using the Knee Society Score (KSS) and the Knee Society Assessment Form, respectively. The mean follow-up was 10 years (range, 5-15 years). Three patients were lost to follow-up. Survival of the prostheses was 98% at 10 years; three prostheses required revision for deep infection, bearing dislocation, and periprosthetic fracture. The mean KSS improved significantly, from 42 and 44 points preoperatively to 90 and 79 points, respectively, at the latest evaluation (P < 0.001); results were excellent in 278 cases, good in 106, fair in 27, and poor in nine. Radiolucent lines were observed in 80 cases; revision arthroplasty was not performed in any of these cases. Complications included deep infection in one patient, bearing dislocation in one, skin necrosis in four, and a supracondylar fracture in one. The cementless LCS rotating-platform total knee arthroplasty is associated with excellent mid- and long-term results for patients with osteoarthritis and rheumatoid arthritis of the knee.

Process for synthesizing titanium carbide, titanium nitride and titanium carbonitride

DOEpatents

Koc, Rasit; Glatzmaier, Gregory C.

1995-01-01

A process for synthesizing titanium carbide, titanium nitride or titanium carbonitride. The process comprises placing particles of titanium, a titanium salt or titanium dioxide within a vessel and providing a carbon-containing atmosphere within the vessel. The vessel is heated to a pyrolysis temperature sufficient to pyrolyze the carbon to thereby coat the particles with a carbon coating. Thereafter, the carbon-coated particles are heated in an inert atmosphere to produce titanium carbide, or in a nitrogen atmosphere to produce titanium nitride or titanium carbonitride, with the heating being of a temperature and time sufficient to produce a substantially complete solid solution.

Biocompatibility and Inflammatory Potential of Titanium Alloys Cultivated with Human Osteoblasts, Fibroblasts and Macrophages

PubMed Central

Markhoff, Jana; Krogull, Martin; Schulze, Christian; Rotsch, Christian; Hunger, Sandra; Bader, Rainer

2017-01-01

The biomaterials used to maintain or replace functions in the human body consist mainly of metals, ceramics or polymers. In orthopedic surgery, metallic materials, especially titanium and its alloys, are the most common, due to their excellent mechanical properties, corrosion resistance, and biocompatibility. Aside from the established Ti6Al4V alloy, shape memory materials such as nickel-titanium (NiTi) have risen in importance, but are also discussed because of the adverse effects of nickel ions. These might be reduced by specific surface modifications. In the present in vitro study, the osteoblastic cell line MG-63 as well as primary human osteoblasts, fibroblasts, and macrophages were cultured on titanium alloys (forged Ti6Al4V, additive manufactured Ti6Al4V, NiTi, and Diamond-Like-Carbon (DLC)-coated NiTi) to verify their specific biocompatibility and inflammatory potential. Additive manufactured Ti6Al4V and NiTi revealed the highest levels of metabolic cell activity. DLC-coated NiTi appeared as a suitable surface for cell growth, showing the highest collagen production. None of the implant materials caused a strong inflammatory response. In general, no distinct cell-specific response could be observed for the materials and surface coating used. In summary, all tested titanium alloys seem to be biologically appropriate for application in orthopedic surgery. PMID:28772412

Biocompatibility and Inflammatory Potential of Titanium Alloys Cultivated with Human Osteoblasts, Fibroblasts and Macrophages.

PubMed

Markhoff, Jana; Krogull, Martin; Schulze, Christian; Rotsch, Christian; Hunger, Sandra; Bader, Rainer

2017-01-10

The biomaterials used to maintain or replace functions in the human body consist mainly of metals, ceramics or polymers. In orthopedic surgery, metallic materials, especially titanium and its alloys, are the most common, due to their excellent mechanical properties, corrosion resistance, and biocompatibility. Aside from the established Ti6Al4V alloy, shape memory materials such as nickel-titanium (NiTi) have risen in importance, but are also discussed because of the adverse effects of nickel ions. These might be reduced by specific surface modifications. In the present in vitro study, the osteoblastic cell line MG-63 as well as primary human osteoblasts, fibroblasts, and macrophages were cultured on titanium alloys (forged Ti6Al4V, additive manufactured Ti6Al4V, NiTi, and Diamond-Like-Carbon (DLC)-coated NiTi) to verify their specific biocompatibility and inflammatory potential. Additive manufactured Ti6Al4V and NiTi revealed the highest levels of metabolic cell activity. DLC-coated NiTi appeared as a suitable surface for cell growth, showing the highest collagen production. None of the implant materials caused a strong inflammatory response. In general, no distinct cell-specific response could be observed for the materials and surface coating used. In summary, all tested titanium alloys seem to be biologically appropriate for application in orthopedic surgery.

Fallon FORGE Well Lithologies

DOE Data Explorer

Doug Blankenship

2016-03-01

x,y,z text file of the downhole lithologic interpretations in the wells in and around the Fallon FORGE site. All the relevant information is in the file header (the spatial reference, the projection etc.) In addition all the fields in the data file are identified in the header.

Process for synthesizing titanium carbide, titanium nitride and titanium carbonitride

DOEpatents

Koc, R.; Glatzmaier, G.C.

1995-05-23

A process is disclosed for synthesizing titanium carbide, titanium nitride or titanium carbonitride. The process comprises placing particles of titanium, a titanium salt or titanium dioxide within a vessel and providing a carbon-containing atmosphere within the vessel. The vessel is heated to a pyrolysis temperature sufficient to pyrolyze the carbon to thereby coat the particles with a carbon coating. Thereafter, the carbon-coated particles are heated in an inert atmosphere to produce titanium carbide, or in a nitrogen atmosphere to produce titanium nitride or titanium carbonitride, with the heating being of a temperature and time sufficient to produce a substantially complete solid solution.

Cementless total hip arthroplasty with a double chevron subtrochanteric shortening osteotomy in patients with Crowe type-IV hip dysplasia.

PubMed

Li, Xigong; Sun, Junying; Lin, Xiangjin; Xu, Sanzhong; Tang, Tiansi

2013-06-01

The authors describe a modified double chevron subtrochanteric shortening osteotomy combined with cementless total hip arthroplasty for Crowe type-IV hip dysplasia. Shortening the femur allows to relax the shortened musculature. This operation was performed in 18 patients (22 hips) between January 2000 and February 2006. The mean follow-up period was 5.6 years (range: 3 to 8 years). The mean amount of femoral subtrochanteric shortening was 38 mm (range: 25 to 60 mm). The mean Harris hip score improved from 47 (range: 35 to 65) preoperatively to 88 points (range: 75 to 97) at final follow-up. The Trendelenburg sign was corrected from positive to negative in 12 of 22 hips. No acetabular or femoral components loosened or required revision during the follow-up period. All osteotomy sites healed in 3 to 6 months without complications. Cementless total hip arthroplasty using the modified double chevron subtrochanteric osteotomy provided good short- to midterm results in all 22 Crowe type-IV hip dislocations. Moreover, it restored the anatomic hip center and the limb length, which contributed to correction of the preoperative limp.

Early bone growth on the surface of titanium implants in rat femur is enhanced by an amorphous diamond coating.

PubMed

Jaatinen, Jarkko J P; Korhonen, Rami K; Pelttari, Alpo; Helminen, Heikki J; Korhonen, Hannu; Lappalainen, Reijo; Kröger, Heikki

2011-08-01

Amorphous diamond (AD) is a durable and compatible biomaterial for joint prostheses. Knowledge regarding bone growth on AD-coated implants and their early-stage osseointegration is poor. We investigated bone growth on AD-coated cementless intramedullary implants implanted in rats. Titanium was chosen as a reference due to its well-known performance. We placed AD-coated and non-coated titanium implants (R(a) ≈ 0.2 μm) into the femoral bone marrow of 25 rats. The animals were divided in 2 groups according to implant coating and they were killed after 4 or 12 weeks. The osseointegration of the implants was examined from hard tissue specimens by measuring the new bone formation on their surface. 4 weeks after the operation, the thickness of new bone in the AD-coated group was greater than that in the non-coated group (15.3 (SD 7.1) μm vs. 7.6 (SD 6.0) μm). 12 weeks after the operation, the thickness of new bone was similar in the non-coated group and in the AD-coated group. We conclude that AD coating of femoral implants can enhance bone ongrowth in rats in the acute, early stage after the operation and might be an improvement over earlier coatings.

Looking west inside of the machine/forge shop at chargin door ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Looking west inside of the machine/forge shop at chargin door of the forging furnace. - U.S. Steel Edgar Thomson Works, Auxiliary Buildings & Shops, Along Monongahela River, Braddock, Allegheny County, PA

TDNiCr (ni-20Cr-2ThO2) forging studies

NASA Technical Reports Server (NTRS)

Filippi, A. M.

1974-01-01

Elevated temperature tensile and stress rupture properties were evaluated for forged TDNiCr (Ni-20Cr-2ThO2) and related to thermomechanical history and microstructure. Forging temperature and final annealed condition had pronounced influences on grain size which, in turn, was related to high temperature strength. Tensile strength improved by a factor of 8 as grain size changed from 1 to 150 microns. Stress-rupture strength was improved by a factor of 3 to 5 by a grain size increase from 10 to 1000 microns. Some contributions to the elevated temperature strength of very large grain material may also occur from the development of a strong texture and a preponderance of small twins. Other conditions promoting the improvement of high temperature strength were: an increase of total reduction, forging which continued the metal deformation inherent in the starting material, a low forging speed, and prior deformation by extrusion. The mechanical properties of optimally forged TDNiCr compared favorably to those of high strength sheet developed for space shuttle application.

Cementless modular intramedullary nail without bone-on-bone fusion as a salvage procedure in chronically infected total knee prosthesis: long-term results.

PubMed

Scarponi, Sara; Drago, Lorenzo; Romanò, Delia; Logoluso, Nicola; Peccati, Andrea; Meani, Enzo; Romanò, Carlo L

2014-02-01

Our purpose was to evaluate long-term results of two-stage cementless intramedullary nailing without achieving bone-to-bone fusion for treating chronically infected total knee arthroplasty (TKA). Thirty-eight patients treated according to the same protocol were retrospectively evaluated for clinical, functional, laboratory and radiological outcomes. Spacer exchange was necessary for infection persistence in one case. At a minimum two year follow-up, 34 patients (89.5%) showed no infection recurrence; among these 34 patients, 29 (85.3%) reported no or moderate pain [visual analogue scale (VAS) ≤3]; mild to moderate handicap (Lequesne Algofunctional Index < 7.5) was observed in 18 patients (52.9%). No patient underwent revision for aseptic loosening, and no nail breakage was observed. Two-stage cementless intramedullary nailing without achieving bone-to-bone fusion is a viable option for treating chronically infected TKA in selected, complex cases.

Research to Conduct an Exploratory Experimental and Analytical Investigation of Alloys

DTIC Science & Technology

1978-03-01

d« (f n«r««a«rv on« 149*111* hv *l«c* f*u0«««> Titanium Aluminides , Alloy Development, Mechemical Properties, Powder Metallurgy, Forging, Joining...Ccmpcsition of Titanium 79 Aluminida Alloy 9 Nuclear Metals Reported REP Titanium 80 Aluminide Powder Size Distribution 10 Phase I, Task I...137 141 24 Chemical Composition of Titanium Aluminide Alloy TMCA Heat 75301 Ti-13.5Al-21.4Nb 25 Isothermal Forging Results 26 Tensile Results

Calculation of recovery plasticity in multistage hot forging under isothermal conditions.

PubMed

Zhbankov, Iaroslav G; Perig, Alexander V; Aliieva, Leila I

2016-01-01

A widely used method for hot forming steels and alloys, especially heavy forging, is the process of multistage forging with pauses between stages. The well-known effect which accompanies multistage hot forging is metal plasticity recovery in comparison with monotonic deformation. A method which takes into consideration the recovery of plasticity in pauses between hot deformations of a billet under isothermal conditions is proposed. This method allows the prediction of billet forming limits as a function of deformation during the forging stage and the duration of the pause between the stages. This method takes into account the duration of pauses between deformations and the magnitude of subdivided deformations. A hot isothermal upsetting process with pauses was calculated by the proposed method. Results of the calculations have been confirmed with experimental data.

Fallon, Nevada FORGE Well 21-31 Wireline Logs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blankenship, Doug

Included are the following wireline logs from the Fallon FORGE Well 21-31. Ormat_Forge 21-31_8.5 inch section: FMI data in PDF and DLIS formats; MSCT data in PDF format; Pressure and Temperature data in PDF, LAS, and DLIS formats; Sonic Scanner data in PDF, DLIS, and LAS formats (LAS format contains Stoneley Slowness, Shear Slowness, and Compressional Slowness logs); Triple Combo in PDF, DLIS, and LAS formats; and USIT data in DLIS and PDF formats. Ormat_Forge_21-31_12.25 inch section: Resistivity data in PDF and LAS formats; Sonic Scanner data in PDF, DLIS, and LAS formats (LAS format contains Stoneley Slowness, Shear Slowness,more » and Compressional Slowness logs); Triple Combo in PDF and LAS formats; and Caliper data in PDF format (DLIS format for caliper data is included in the Sonic Scanner DLIS).« less

Effect of Cold Forging on Microstructure and MechanicalProperties of Al/SiC Composites

NASA Astrophysics Data System (ADS)

Hanamantraygouda, M. B.; Shivakumar, B. P., Dr; Siddappa, P. N.; Sampathkumar, L.; Prashanth, L.

2018-02-01

The objective of this work was to investigate the effect of cold forging on mechanical properties and microstructural study of Al MMCs, at different wt% of SiC and forging cycle. The Al-SiC composite material was fabricated by stir casting method at different weight percentage of SiC such as 2.5, 5, 7.5 and 10%. Further, the deformation characteristics during open-die forging of Al-SiC composite at cold conditions was investigated. Cast and forged composite material was subjected to hardness test, tensile test and impact test. The grain size, microstructure behaviour was investigated using optical microscope. The results show that hardness and strength of Al-SiC composite increases and ductility decreases as compared to Al alloy in both as-cast and forged conditions. Optical microscope images showed that the distribution of SiC in Al matrix was more homogeneous in a forged composite as compared to cast one and reduction of porosity was found. Further, it showed that due to forging cycle the grain size was reduced by 30% to 35% from initial size.

Finite element simulations and experimental investigations on ductile fracture in cold forging of aluminum alloy

NASA Astrophysics Data System (ADS)

Amiri, Amir; Nikpour, Amin; Saraeian, Payam

2018-05-01

Forging is one of the manufacturing processes of aluminium parts which has two major categories: called hot and cold forging. In the cold forging, the dimensional and geometrical accuracy of final part is high. However, fracture may occur in some aluminium alloys during the process because of less workability. Fracture in cold forging can be in the form of ductile, brittle or combination of both depending on the alloy type. There are several criteria for predicting fracture in cold forging. In this study, cold forging process of 6063 aluminium alloy for three different parts is simulated in order to predict fracture. The results of numerical simulations of Freudenthal criterion is in conformity with experimental tests.

DataForge: Modular platform for data storage and analysis

NASA Astrophysics Data System (ADS)

Nozik, Alexander

2018-04-01

DataForge is a framework for automated data acquisition, storage and analysis based on modern achievements of applied programming. The aim of the DataForge is to automate some standard tasks like parallel data processing, logging, output sorting and distributed computing. Also the framework extensively uses declarative programming principles via meta-data concept which allows a certain degree of meta-programming and improves results reproducibility.

Influence of different sizes of composite femora on the biomechanical behavior of cementless hip prosthesis.

PubMed

Schmidutz, Florian; Woiczinski, Mathias; Kistler, Manuel; Schröder, Christian; Jansson, Volkmar; Fottner, Andreas

2017-01-01

For the biomechanical evaluation of cementless stems different sizes of composite femurs have been used in the literature. However, the impact of different specimen sizes on test results is unknown. To determine the potential effect of femur size the biomechanical properties of a conventional stem (CLS Spotorno) were examined in 3 different sizes (small, medium and large composite Sawbones®). Primary stability was tested under physiologically adapted dynamic loading conditions measuring 3-dimensional micromotions. For the small composite femur the dynamic load needed to be adapted since fractures occurred when reaching 1700N. Additionally, surface strain distribution was recorded before and after implantation to draw conclusions about the tendency for stress shielding. All tested sizes revealed similar micromotions only reaching a significant different level at one measurement point. The highest micromotions were observed at the tip of the stems exceeding the limit for osseous integration of 150μm. Regarding strain distribution the highest strain reduction after implantation was registered in all sizes at the level of the lesser trochanter. Specimen size seems to be a minor influence factor for biomechanical evaluation of cementless stems. However, the small composite femur is less suitable for biomechanical testing since this size failed under physiological adapted loads. For the CLS Spotorno osseous integration is unlikely at the tip of the stem and the tendency for stress shielding is the highest at the level of the lesser trochanter. Copyright © 2016 Elsevier Ltd. All rights reserved.

Deformation processes in forging ceramics

NASA Technical Reports Server (NTRS)

Cannon, R. M.; Rhodes, W. H.

1973-01-01

The deformation processes involved in the forging of refractory ceramic oxides were investigated. A combination of mechanical testing and forging was utilized to investigate both the flow and fracture processes involved. Deformation studies of very fine grain Al203 revealed an apparent transition in behavior, characterized by a shift in the strain rate sensitivity from 0.5 at low stresses to near unity at higher stresses. The behavior is indicative of a shift in control between two dependent mechanisms, one of which is indicated to be cation limited diffusional creep with significant boundary enhancement. The possible contributions of slip, indicated by crystallographic texture, interface control of the diffusional creep and inhomogeneous boundary sliding are also discussed. Additional experiments indicated an independence of deformation behavior on MgO doping and retained hot pressing impurities, at least for ultrafine grained material, and also an independence of test atmosphere.

Prediction of Microstructure in High-Strength Ductile Forging Parts

NASA Astrophysics Data System (ADS)

Urban, M.; Keul, C.; Back, A.; Bleck, W.; Hirt, G.

2010-06-01

Governmental, environmental and economic demands call for lighter, stiffer and at the same time cheaper products in the vehicle industry. Especially safety relevant parts have to be stiff and at the same time ductile. The strategy of this project was to improve the mechanical properties of forging steel alloys by employing a high-strength and ductile bainitic microstructure in the parts while maintaining cost effective process chains to reach these goals for high stressed forged parts. Therefore, a new steel alloy combined with an optimized process chain has been developed. To optimize the process chain with a minimum of expensive experiments, a numerical approach was developed to predict the microstructure of the steel alloy after the process chain based on FEM simulations of the forging and cooling combined with deformation-time-temperature-transformation-diagrams.

Independent predictors of failure up to 7.5 years after 35 386 single-brand cementless total hip replacements: a retrospective cohort study using National Joint Registry data.

PubMed

Jameson, S S; Baker, P N; Mason, J; Rymaszewska, M; Gregg, P J; Deehan, D J; Reed, M R

2013-06-01

The popularity of cementless total hip replacement (THR) has surpassed cemented THR in England and Wales. This retrospective cohort study records survival time to revision following primary cementless THR with the most common combination (accounting for almost a third of all cementless THRs), and explores risk factors independently associated with failure, using data from the National Joint Registry for England and Wales. Patients with osteoarthritis who had a DePuy Corail/Pinnacle THR implanted between the establishment of the registry in 2003 and 31 December 2010 were included within analyses. There were 35 386 procedures. Cox proportional hazard models were used to analyse the extent to which the risk of revision was related to patient, surgeon and implant covariates. The overall rate of revision at five years was 2.4% (99% confidence interval 2.02 to 2.79). In the final adjusted model, we found that the risk of revision was significantly higher in patients receiving metal-on-metal (MoM: hazard ratio (HR) 1.93, p < 0.001) and ceramic-on-ceramic bearings (CoC: HR 1.55, p = 0.003) compared with the best performing bearing (metal-on-polyethylene). The risk of revision was also greater for smaller femoral stems (sizes 8 to 10: HR 1.82, p < 0.001) compared with mid-range sizes. In a secondary analysis of only patients where body mass index (BMI) data were available (n = 17 166), BMI ≥ 30 kg/m(2) significantly increased the risk of revision (HR 1.55, p = 0.002). The influence of the bearing on the risk of revision remained significant (MoM: HR 2.19, p < 0.001; CoC: HR 2.09, p = 0.001). The risk of revision was independent of age, gender, head size and offset, shell, liner and stem type, and surgeon characteristics. We found significant differences in failure between bearing surfaces and femoral stem size after adjustment for a range of covariates in a large cohort of single-brand cementless THRs. In this study of procedures performed since 2003, hard bearings had

High yttria ferritic ODS steels through powder forging

NASA Astrophysics Data System (ADS)

Kumar, Deepak; Prakash, Ujjwal; Dabhade, Vikram V.; Laha, K.; Sakthivel, T.

2017-05-01

Oxide dispersion strengthened (ODS) steels are being developed for future nuclear reactors. ODS Fe-18%Cr-2%W-0.2%Ti steels with 0, 0.35, 0.5, 1 and 1.5% Y2O3 (all compositions in weight%) dispersion were fabricated by mechanical alloying of elemental powders. The powders were placed in a mild steel can and forged in a stream of hydrogen gas at 1473 K. The steels were forged again to final density. The strength of ODS steel increased with yttria content. Though this was accompanied by a decrease in tensile elongation, all the steels showed significant ductility. The ductility in high yttria alloys may be attributed to improved inter-particle bonding between milled powders due to reduction of surface oxides by hydrogen. This may permit development of ODS steels with yttria contents higher than the conventional limit of 0.5%. It is suggested that powder forging is a promising route to fabricate ODS steels with high yttria contents and improved ductility.

Midterm Outcomes of Revision Total Hip Arthroplasty With the Use of a Multihole Highly-Porous Titanium Shell.

PubMed

Delanois, Ronald E; Gwam, Chukwuweike U; Mohamed, Nequesha; Khlopas, Anton; Chughtai, Morad; Malkani, Arthur L; Mont, Michael A

2017-09-01

We are reporting on the minimum 5-year outcomes of patients who underwent revision total hip arthroplasty (THA) using a specific highly-porous titanium shell. We assessed (1) aseptic and all-cause survivorship; (2) functional outcomes; (3) complications; and (4) radiographic outcomes. Two hospital databases were evaluated for patients who underwent revision THA due to component instability or aseptic loosening using a cementless highly-porous titanium shell between September 2006 and December 2011. This yielded 35 patients who had a mean age of 61 years (range 14-88 years). Patients had a mean follow-up of 6 years (minimum 5 years). All-cause and aseptic survivorship of the shell was calculated. Functional outcomes were assessed using the Harris Hip Score. We determined the incidence of postoperative complications and performed radiographic evaluation of pelvic radiographs from regular office visits. The aseptic survivorship of the acetabular component was 97% (95% confidence interval; 8.1-9.5). The all-cause survivorship of the acetabular component was 91% (95% confidence interval; 7.3-8.1). One patient had an aseptic failure and 2 patients had septic failures. The mean postoperative Harris Hip Score was 76 points (range, 61-91 points). Excluding the aseptic and septic failures, there was no osteolysis or progressive radiolucencies present on radiographic evaluation at final follow-up. At a minimum of 5-year follow-up, the highly-porous titanium acetabular revision shell has excellent survivorship and functional outcomes. Although long-term follow-up is needed to further monitor these implants, the results are promising and demonstrate that this prosthesis may be an excellent option for patients undergoing revision THA. Copyright © 2017 Elsevier Inc. All rights reserved.

Temperature Contours around Milford FORGE site

DOE Data Explorer

Joe Moore

2016-03-09

This submission contains several ArcGIS shapefiles, each with Temperature contour lines at different depths. Subsurface temperature were important for characterizing the geothermal system beneath the FORGE site in Milford, Utah.

Design and Analysis of a Forging Die for Manufacturing of Multiple Connecting Rods

NASA Astrophysics Data System (ADS)

Megharaj, C. E.; Nagaraj, P. M.; Jeelan Pasha, K.

2016-09-01

This paper demonstrates to utilize the hammer capacity by modifying the die design such that forging hammer can manufacture more than one connecting rod in a given forging cycle time. To modify the die design study is carried out to understand the parameters that are required for forging die design. By considering these parameters, forging die is designed using design modelling tool solid edge. This new design now can produce two connecting rods in same capacity hammer. The new design is required to validate by verifying complete filing of metal in die cavities without any defects in it. To verify this, analysis tool DEFORM 3D is used in this project. Before start of validation process it is require to convert 3D generated models in to. STL file format to import the models into the analysis tool DEFORM 3D. After importing these designs they are analysed for material flow into the cavities and energy required to produce two connecting rods in new forging die design. It is found that the forging die design is proper without any defects and also energy graph shows that the forging energy required to produce two connecting rods is within the limit of that hammer capacity. Implementation of this project increases the production of connecting rods by 200% in less than previous cycle time.

Development and efficiency assessment of process lubrication for hot forging

NASA Astrophysics Data System (ADS)

Kargin, S.; Artyukh, Viktor; Ignatovich, I.; Dikareva, Varvara

2017-10-01

The article considers innovative technologies in testing and production of process lubricants for hot bulk forging. There were developed new compositions of eco-friendly water-graphite process lubricants for hot extrusion and forging. New approaches to efficiency assessment of process lubricants are developed and described in the following article. Laboratory and field results are presented.

76 FR 8773 - Forged Stainless Steel Flanges From India and Taiwan

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-15

... INTERNATIONAL TRADE COMMISSION [Investigation Nos. 731-TA-639 and 640 (Third Review)] Forged Stainless Steel Flanges From India and Taiwan AGENCY: United States International Trade Commission. ACTION... determine whether revocation of the antidumping duty orders on forged stainless steel flanges from India and...

Analysis of the thermo-mechanical deformations in a hot forging tool by numerical simulation

NASA Astrophysics Data System (ADS)

L-Cancelos, R.; Varas, F.; Martín, E.; Viéitez, I.

2016-03-01

Although programs have been developed for the design of tools for hot forging, its design is still largely based on the experience of the tool maker. This obliges to build some test matrices and correct their errors to minimize distortions in the forged piece. This phase prior to mass production consumes time and material resources, which makes the final product more expensive. The forging tools are usually constituted by various parts made of different grades of steel, which in turn have different mechanical properties and therefore suffer different degrees of strain. Furthermore, the tools used in the hot forging are exposed to a thermal field that also induces strain or stress based on the degree of confinement of the piece. Therefore, the mechanical behaviour of the assembly is determined by the contact between the different pieces. The numerical simulation allows to analyse different configurations and anticipate possible defects before tool making, thus, reducing the costs of this preliminary phase. In order to improve the dimensional quality of the manufactured parts, the work presented here focuses on the application of a numerical model to a hot forging manufacturing process in order to predict the areas of the forging die subjected to large deformations. The thermo-mechanical model developed and implemented with free software (Code-Aster) includes the strains of thermal origin, strains during forge impact and contact effects. The numerical results are validated with experimental measurements in a tooling set that produces forged crankshafts for the automotive industry. The numerical results show good agreement with the experimental tests. Thereby, a very useful tool for the design of tooling sets for hot forging is achieved.

Characterization of Cracking and Crack Growth Properties of the C5A Aircraft Tie-Box Forging

NASA Technical Reports Server (NTRS)

Piascik, Robert S.; Smith, Stephen W.; Newman, John A.; Willard, Scott A.

2003-01-01

Detailed destructive examinations were conducted to characterize the integrity and material properties of two aluminum alloy (7075-T6) horizontal stabilizer tie box forgings removed.from US. Air Force C5A and C5B transport aircraft. The C5B tie box forging was,found to contain no evidence of cracking. Thirteen cracks were found in the CSA,forging. All but one of the cracks observed in the C5A component were located along the top cap region (one crack was located in the bottom cap region). The cracks in the C5A component initiated at fastener holes and propagated along a highly tunneled intergranular crack path. The tunneled crack growth configuration is a likelv result of surface compressive stress produced during peening of the .forging suijace. The tie box forging ,fatigue crack growth, fracture and stress corrosion cracking (SCC) properties were characterized. Reported herein are the results of laboratory air ,fatigue crack growth tests and 95% relative humidity SCC tests conducted using specimens machined from the C5A ,forging. SCC test results revealed that the C5A ,forging material was susceptible to intergranular environmental assisted cracking: the C5A forging material exhibited a SCC crack-tip stress-intensity factor threshold of less than 6 MPadn. Fracture toughness tests revealed that the C5A forging material exhibited a fracture toughness that was 25% less than the C5B forging. The C5A forging exhibited rapid laboratory air fatigue crack growth rates having a threshold crack-tip stress-intensity factor range of less than 0.8 MPa sup m. Detailed fractographic examinations revealed that the ,fatigue crack intergranular growth crack path was similar to the cracking observed in the C5A tie box forging. Because both fatigue crack propagation and SCC exhibit similar intergranular crack path behavior, the damage mechanism resulting in multi-site cracking of tie box forgings cannot be determined unless local cyclic stresses can be quantified.

West Flank Coso FORGE Magnetotelluric 3D Data

DOE Data Explorer

Doug Blankenship

2016-01-01

This is the 3D version of the MT data for the West Flank FORGE area.The Coso geothermal field has had three Magnetotelluric (MT) datasets collected including surveys in 2003, 2006, and 2011. The final collection, in 2011, expanded the survey to the west and covers the West Flank of FORGE area.This most recent data set was collected by Schlumberger/WesternGeco and inverted by the WesternGeco GeoSolutions Integrated EM Center of Excellence in Milan, Italy; the 2003 and 2006 data were integrated for these inversions in the present study.

[Ex vivo microCT analysis of possible microfractures of the femoral head during implantation of a cementless hip resurfacing femoral component].

PubMed

Lerch, M; Olender, G; von der Höh, N; Thorey, F; von Lewinski, G; Meyer-Lindenberg, A; Windhagen, H; Hurschler, C

2009-01-01

Microfractures of the femoral head during implantation of the femoral components are suspected to be a cause of fractures at the implant/neck junction which represent a common failure mode in hip resurfacing arthroplasty. Callus formation observed in femoral head retrievals suggests the occurrence of microfractures inside the femoral head, which might be inadvertently caused by the surgeon during implantation. The aim of this biomechanical study was to analyse whether or not the implantation of a cementless femoral component hip resurfacing system causes microfractures in the femoral head. After the preparation of 20 paired human cadaveric femoral heads, the cementless femoral component ESKA Typ BS (ESKA Implants GmbH & Co., Lübeck) was implanted on 9 specimens with an impaction device that generates 4.5 kN impaction force. On 9 specimens the femoral component was implanted by hand. One head was used as a fracture model, 1 specimen served as control without manipulation. The femoral component used for impaction was equipped with hinges to enable its removal without further interfering with the bone stock. Specimens were scanned with a microCT device before and after impaction and the microCT datasets before and after impaction were compared to identify possible microfractures. Twenty strikes per hand or with the impaction device provided sufficient implant seating. Neither the macroscopic examination nor the 2-dimensional microCT analysis revealed any fractures of the femoral heads after impaction. At least macroscopically and in the 2-dimensional microCT analysis, implantation of the cementless hip resurfacing femoral component ESKA Typ BS with 4.5 kN or by hand does not seem to cause fractures of the femoral head. Georg Thieme Verlag KG Stuttgart, New York.

The cementless Bicontact stem in a prospective dual-energy X-ray absorptiometry study.

PubMed

Lerch, Matthias; Kurtz, Agnes; Windhagen, Henning; Bouguecha, Anas; Behrens, Bernd A; Wefstaedt, Patrick; Stukenborg-Colsman, Christina M

2012-11-01

The cementless Bicontact total hip arthroplasty (THA) system (AESCULAP AG, Tuttlingen, Germany) was introduced in 1986/1987 and has been in successful clinical use in an unaltered form up to today. Although good long-term results with the Bicontact stem have been published, it is questionable whether the implant provides the criteria for a state-of-the-art stem regarding proximal bone stock preservation. The purpose of the study was to monitor the periprosthetic bone mineral density (BMD) in a prospective two-year follow-up dual-energy X-ray absorptiometry (DEXA) study. After power analysis, a consecutive series of 25 patients with unilateral Bicontact stem implantation was examined clinically and underwent DEXA examinations. Scans of seven regions of interest were taken preoperatively and at one week, six months, and one and two years. One patient required stem revision due to a deep infection. The Harris Hip Score increased significantly by 44 points. The most significant bone loss was observed in the calcar region (R7) in the first six months (-19.2 %). It recovered in the following 18 months to -8.5 %. The BMD in the greater trochanter dropped significantly after six months and remained stable at this level. BMD exceeded baseline values in distal regions and even more in the lesser trochanter region after two years. We conclude that the Bicontact stem provides adequate proximal bone stock preservation. We observed some signs of stress shielding at the tip of the stem, which is inevitable to some degree in THA with cementless straight stems. However, in this prospective DEXA investigation, we showed that proximal off-loading does not occur after THA with the Bicontact system. Thus, we believe that this stem is still a state-of-the-art implant.

Comparative Thermal Aging Effects on PM-HIP and Forged Inconel 690

NASA Astrophysics Data System (ADS)

Bullens, Alexander L.; Bautista, Esteban; Jaye, Elizabeth H.; Vas, Nathaniel L.; Cain, Nathan B.; Mao, Keyou; Gandy, David W.; Wharry, Janelle P.

2018-03-01

This study compares thermal aging effects in Inconel 690 (IN690) produced by forging and powder metallurgy with hot isostatic pressing (PM-HIP). Isothermal aging is carried out over 400-800°C for up to 1000 h and then metallography and nanoindentation are utilized to relate grain microstructure with hardness and yield strength. The PM-HIP IN690 maintains a constant grain size through all aging conditions, while the forged IN690 exhibits limited grain growth at the highest aging temperature and longest aging time. The PM-HIP IN690 exhibits comparable mechanical integrity as the forged material throughout aging: hardness and yield strength are unchanged with 100 h aging, but increase after 1000 h aging at all temperatures. In both the PM-HIP and forged IN690, the Hall-Petch relationship for Ni-based superalloys predicts yield strength for 0-100 h aged specimens, but underestimates yield strength in the 1000 h aged specimens because of thermally induced precipitation.

Mesh morphing for finite element analysis of implant positioning in cementless total hip replacements.

PubMed

Bah, Mamadou T; Nair, Prasanth B; Browne, Martin

2009-12-01

Finite element (FE) analysis of the effect of implant positioning on the performance of cementless total hip replacements (THRs) requires the generation of multiple meshes to account for positioning variability. This process can be labour intensive and time consuming as CAD operations are needed each time a specific orientation is to be analysed. In the present work, a mesh morphing technique is developed to automate the model generation process. The volume mesh of a baseline femur with the implant in a nominal position is deformed as the prosthesis location is varied. A virtual deformation field, obtained by solving a linear elasticity problem with appropriate boundary conditions, is applied. The effectiveness of the technique is evaluated using two metrics: the percentages of morphed elements exceeding an aspect ratio of 20 and an angle of 165 degrees between the adjacent edges of each tetrahedron. Results show that for 100 different implant positions, the first and second metrics never exceed 3% and 3.5%, respectively. To further validate the proposed technique, FE contact analyses are conducted using three selected morphed models to predict the strain distribution in the bone and the implant micromotion under joint and muscle loading. The entire bone strain distribution is well captured and both percentages of bone volume with strain exceeding 0.7% and bone average strains are accurately computed. The results generated from the morphed mesh models correlate well with those for models generated from scratch, increasing confidence in the methodology. This morphing technique forms an accurate and efficient basis for FE based implant orientation and stability analysis of cementless hip replacements.

Impact of a learning curve on the survivorship of 4802 cementless total hip arthroplasties.

PubMed

Magill, P; Blaney, J; Hill, J C; Bonnin, M P; Beverland, D E

2016-12-01

Our aim was to report survivorship data and lessons learned with the Corail/Pinnacle cementless total hip arthroplasty (THA) system. Between August 2005 and March 2015, a total of 4802 primary cementless Corail/Pinnacle THAs were performed in 4309 patients. In March 2016, we reviewed these hips from a prospectively maintained database. A total of 80 hips (1.67%) have been revised which is equivalent to a cumulative risk of revision of 2.5% at ten years. The rate of revision was not significantly higher in patients aged ≥ 70 years (p = 0.93). The leading indications for revision were instability (n = 22, 0.46%), infection (n = 20, 0.42%), aseptic femoral loosening (n = 15, 0.31%) and femoral fracture (n = 6, 0.12%). There were changes in the surgical technique with respect to the Corail femoral component during the ten-year period involving a change to collared components and a trend towards larger size. These resulted in a decrease in the rate of iatrogenic femoral fracture and a decrease in the rate of aseptic loosening. The rate of revision in this series is comparable with the best performing THAs in registry data. Most revisions were not directly related to the implants. Despite extensive previous experience with cemented femoral components, the senior author noted a learning curve requiring increased focus on primary stability. The number of revisions related to the femoral component is reducing. Any new technology has a learning curve that may be independent of surgical experience. Cite this article: Bone Joint J 2016;98-B:1589-96. ©2016 The British Editorial Society of Bone & Joint Surgery.

Superplastic forging nitride ceramics

DOEpatents

Panda, Prakash C.; Seydel, Edgar R.; Raj, Rishi

1988-03-22

The invention relates to producing relatively flaw free silicon nitride ceramic shapes requiring little or no machining by superplastic forging This invention herein was made in part under Department of Energy Grant DE-AC01-84ER80167, creating certain rights in the United States Government. The invention was also made in part under New York State Science and Technology Grant SB1R 1985-10.

Valley Forge alternative transportation feasibility study

DOT National Transportation Integrated Search

2004-06-01

NPS, as part of their General Management Plan (GMP) realignment, worked with Volpe to develop a series of alternative transportation methods in Valley Forge National Historical Park. Automobiles are the predominant means of transportation in the park...

Titanium

USGS Publications Warehouse

Woodruff, Laurel G.; Bedinger, George M.; Piatak, Nadine M.; Schulz, Klaus J.; DeYoung,, John H.; Seal, Robert R.; Bradley, Dwight C.

2017-12-19

Titanium is a mineral commodity that is essential to the smooth functioning of modern industrial economies. Most of the titanium produced is refined into titanium dioxide, which has a high refractive index and is thus able to impart a durable white color to paint, paper, plastic, rubber, and wallboard. Because of their high strength-to-weight ratio and corrosion resistance, titanium metal and titanium metal alloys are used in the aerospace industry as well as for welding rod coatings, biological implants, and consumer goods.Ilmenite and rutile are currently the principal titanium-bearing ore minerals, although other minerals, including anatase, perovskite, and titanomagnetite, could have economic importance in the future. Ilmenite is currently being mined from two large magmatic deposits hosted in rocks of Proterozoic-age anorthosite plutonic suites. Most rutile and nearly one-half of the ilmenite produced are from heavy-mineral alluvial, fluvial, and eolian deposits. Titanium-bearing minerals occur in diverse geologic settings, but many of the known deposits are currently subeconomic for titanium because of complications related to the mineralogy or because of the presence of trace contaminants that can compromise the pigment production process.Global production of titanium minerals is currently dominated by Australia, Canada, Norway, and South Africa; additional amounts are produced in Brazil, India, Madagascar, Mozambique, Sierra Leone, and Sri Lanka. The United States accounts for about 4 percent of the total world production of titanium minerals and is heavily dependent on imports of titanium mineral concentrates to meet its domestic needs.Titanium occurs only in silicate or oxide minerals and never in sulfide minerals. Environmental considerations for titanium mining are related to waste rock disposal and the impact of trace constituents on water quality. Because titanium is generally inert in the environment, human health risks from titanium and titanium

Fallon, Nevada FORGE Geodetic Data

DOE Data Explorer

Blankenship, Doug; Eneva, Mariana; Hammond, William

2018-02-01

Fallon FORGE InSAR and geodetic GPS deformation data. InSAR shapefiles are packaged together as .MPK (ArcMap map package, compatible with other GIS platforms), and as .CSV comma-delimited plaintext. GPS data and additional metadata are linked to the Nevada Geodetic Laboratory database at the Univ. of Nevada, Reno (UNR).

Tensile and creep properties of titanium-vanadium, titanium-molybdenum, and titanium-niobium alloys

NASA Technical Reports Server (NTRS)

Gray, H. R.

1975-01-01

Tensile and creep properties of experimental beta-titanium alloys were determined. Titanium-vanadium alloys had substantially greater tensile and creep strength than the titanium-niobium and titanium-molybdenum alloys tested. Specific tensile strengths of several titanium-vanadium-aluminum-silicon alloys were equivalent or superior to those of commercial titanium alloys to temperatures of 650 C. The Ti-50V-3Al-1Si alloy had the best balance of tensile strength, creep strength, and metallurgical stability. Its 500 C creep strength was far superior to that of a widely used commercial titanium alloy, Ti-6Al-4V, and almost equivalent to that of newly developed commercial titanium alloys.

Deformation behavior of TC6 alloy in isothermal forging

NASA Astrophysics Data System (ADS)

Li, Xiaoli; Li, Miaoquan; Zhu, Dasong; Xiong, Aiming

2005-10-01

Isothermal compression of the TC6 alloy was carried out in a Thermecmaster-Z (Wuhan Iron and Steel Corporation, P.R. China) simulator at deformation temperatures of 800˜1040 °C, strain rates of 0.001˜50.0 s-1, and maximum height reduction of 50%. The deformation behavior of the TC6 alloy in isothermal forging was characterized based on stress-strain behavior and kinetic analysis. The activation energy of deformation obtained in the isothermal forging of the TC6 alloy was 267.49 kJ/mol in the β phase region and 472.76 kJ/mol in the α+β phase region. The processing map was constructed based on the dynamic materials model, and the optimal deformation parameters were obtained. Constitutive equations describing the flow stress as a function of strain rate, strain, and deformation temperature were proposed for the isothermal forging of the TC6 alloy, and a good agreement between the predicted and experimental stress-strain curves was achieved.

Fallon, Nevada FORGE Fluid Geochemistry

DOE Data Explorer

Blankenship, Doug; Ayling, Bridget

2018-03-13

Fluid geochemistry analysis for wells supporting the Fallon FORGE project. Samples were collected from geothermal wells using standard geothermal water sampling techniques, including filtration and acidification of the cation sample to pH < 2 prior to geochemical analysis. Analyses after 2005 were done in reputable commercial laboratories that follow standard protocols for aqueous chemistry analysis.

Subsidence of a cementless femoral component influenced by body weight and body mass index.

PubMed

Stihsen, Christoph; Radl, Roman; Keshmiri, Armin; Rehak, Peter; Windhager, Reinhard

2012-05-01

This trial was designed to evaluate the impact of physical characteristics such as body mass index, body weight and height on distal stem migration of a cementless femoral component, as the influence of obesity on the outcome of THA is still debated in literature and conflicting results have been found. In this retrospective cohort study, migration patterns for 102 implants were analysed using the Einzel-Bild-Roentgen-Analyse (EBRA-FCA, femoral component analysis). In all cases the Vision 2000 stem was implanted and combined with the Duraloc acetabular component (DePuy, Warsaw, Indiana). The mean follow-up was 93 months. EBRA-FCA evaluations revealed a mean subsidence of 1.38 mm after two years, 2.06 mm after five and 2.24 mm after seven years. Five stems loosened aseptically. Correlation between increased migration over the whole period and aseptic loosening was highly significant (p < 0.001). Surgical technique had a significant influence on migration and stem stability (p = 0.002) but physical patient characteristics such as body weight over 75 kg and height over 165 cm also significantly influenced stem subsidence towards progressive migration (p = 0.001, p < 0.001). However, a high BMI did not trigger progressive stem migration (p = 0.87). Being of the male gender raised the odds for increased migration (p = 0.03). Physical characteristics such as body weight and height showed significant influence on migration patterns of this cementless femoral component. The operating surgeon should be aware that body weight above 75 kg and height over 165 cm may trigger increased stem migration and the surgeon should aim to fit these prostheses as tightly as possible. However this study demonstrates that a high BMI does not trigger progressive stem migration. Further investigations are needed to confirm our findings.

Utah FORGE Site Location, Datasets, and Models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Joe Moore

This submission includes the geographic extent shapefile of the Milford FORGE site located in Utah, along with a shapefile of seismometer positions throughout the area, and models of basin depth and potentiometric contours.

Primary stability of a cementless acetabular cup in a cohort of patient-specific finite element models.

PubMed

O'Rourke, Dermot; Al-Dirini, Rami Ma; Taylor, Mark

2018-03-01

The primary stability achieved during total hip arthroplasty determines the long-term success of cementless acetabular cups. Pre-clinical finite element testing of cups typically use a model of a single patient and assume the results can be extrapolated to the general population. This study explored the variability in predicted primary stability of a Pinnacle ® cementless acetabular cup in 103 patient-specific finite element models of the hemipelvis and examined the association between patient-related factors and the observed variability. Cups were inserted by displacement-control into the FE models and then a loading configuration simulating a complete level gait cycle was applied. The cohort showed a range of polar gap of 284-1112 μm and 95th percentile composite peak micromotion (CPM) of 18-624 μm. Regression analysis was not conclusive on the relationship between patient-related factors and primary stability. No relationship was found between polar gap and micromotion. However, when the patient-related factors were categorised into quartile groups, trends suggested higher polar gaps occurred in subjects with small and shallow acetabular geometries and cup motion during gait was affected most by low elastic modulus and high bodyweight. The variation in primary stability in the cohort for an acetabular cup with a proven clinical track record may provide benchmark data when evaluating new cup designs. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1012-1023, 2018. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Identification of forged Bank of England £20 banknotes using IR spectroscopy

NASA Astrophysics Data System (ADS)

Sonnex, Emily; Almond, Matthew J.; Baum, John V.; Bond, John W.

2014-01-01

Bank of England notes of £20 denomination have been studied using infrared spectroscopy in order to generate a method to identify forged notes. An aim of this work was to develop a non-destructive method so that a small, compact Fourier transform infrared spectrometer (FT-IR) instrument could be used by bank workers, police departments or others such as shop assistants to identify forged notes in a non-lab setting. The ease of use of the instrument is the key to this method, as well as the relatively low cost. The presence of a peak at 1400 cm-1 arising from νasym (CO32-) from the blank paper section of a forged note proved to be a successful indicator of the note's illegality for the notes that we studied. Moreover, differences between the spectra of forged and genuine £20 notes were observed in the ν(OH) (ca. 3500 cm-1), ν(Csbnd H) (ca. 2900 cm-1) and ν(Cdbnd O) (ca. 1750 cm-1) regions of the IR spectrum recorded for the polymer film covering the holographic strip. In cases where these simple tests fail, we have shown how an infrared microscope can be used to further differentiate genuine and forged banknotes by producing infrared maps of selected areas of the note contrasting inks with background paper.

Identification of forged Bank of England £20 banknotes using IR spectroscopy.

PubMed

Sonnex, Emily; Almond, Matthew J; Baum, John V; Bond, John W

2014-01-24

Bank of England notes of £20 denomination have been studied using infrared spectroscopy in order to generate a method to identify forged notes. An aim of this work was to develop a non-destructive method so that a small, compact Fourier transform infrared spectrometer (FT-IR) instrument could be used by bank workers, police departments or others such as shop assistants to identify forged notes in a non-lab setting. The ease of use of the instrument is the key to this method, as well as the relatively low cost. The presence of a peak at 1400 cm(-1) arising from νasym (CO3(2-)) from the blank paper section of a forged note proved to be a successful indicator of the note's illegality for the notes that we studied. Moreover, differences between the spectra of forged and genuine £20 notes were observed in the ν(OH) (ca. 3500 cm(-1)), ν(C-H) (ca. 2900 cm(-1)) and ν(C=O) (ca. 1750 cm(-1)) regions of the IR spectrum recorded for the polymer film covering the holographic strip. In cases where these simple tests fail, we have shown how an infrared microscope can be used to further differentiate genuine and forged banknotes by producing infrared maps of selected areas of the note contrasting inks with background paper. Copyright © 2013 Elsevier B.V. All rights reserved.

Intersubjective decision-making for computer-aided forging technology design

NASA Astrophysics Data System (ADS)

Kanyukov, S. I.; Konovalov, A. V.; Muizemnek, O. Yu.

2017-12-01

We propose a concept of intersubjective decision-making for problems of open-die forging technology design. The intersubjective decisions are chosen from a set of feasible decisions using the fundamentals of the decision-making theory in fuzzy environment according to the Bellman-Zadeh scheme. We consider the formalization of subjective goals and the choice of membership functions for the decisions depending on subjective goals. We study the arrangement of these functions into an intersubjective membership function. The function is constructed for a resulting decision, which is chosen from a set of feasible decisions. The choice of the final intersubjective decision is discussed. All the issues are exemplified by a specific technological problem. The considered concept of solving technological problems under conditions of fuzzy goals allows one to choose the most efficient decisions from a set of feasible ones. These decisions correspond to the stated goals. The concept allows one to reduce human participation in automated design. This concept can be used to develop algorithms and design programs for forging numerous types of forged parts.

Treatment of Crowe Type-IV Hip Dysplasia Using Cementless Total Hip Arthroplasty and Double Chevron Subtrochanteric Shortening Osteotomy: A 5- to 10-Year Follow-Up Study.

PubMed

Li, Xigong; Lu, Yang; Sun, Junying; Lin, Xiangjin; Tang, Tiansi

2017-02-01

The purpose of this study was to evaluate the functional and radiographic results of patients with Crowe type-IV hip dysplasia treated by cementless total hip arthroplasty and double chevron subtrochanteric osteotomy. From January 2000 to February 2006, cementless total hip arthroplasty with a double chevron subtrochanteric shortening osteotomy was performed on 18 patients (22 hips) with Crowe type-IV dysplasia. The acetabular cup was placed in the position of the anatomic hip center, and subtrochanteric femoral shortening osteotomy was performed with the use of a double chevron design. The clinical and radiographic outcomes were reviewed with a mean follow-up of 6.5 years (5-10 years). The mean amount of femoral subtrochanteric shortening was 38 mm (25-60 mm). All osteotomy sites were healed by 3-6 months without complications. The mean Harris Hip Score improved significantly from 47 points (35-65 points) preoperatively to 88 points (75-97 points) at the final follow-up. The Trendelenburg sign was corrected from a positive preoperative status to a negative postoperative status in 12 of 22 hips. No acetabular and femoral components have loosened or required revision during the period of follow-up. Cementless total hip arthroplasty using double chevron subtrochanteric osteotomy allowed for restoration of anatomic hip center with safely functional limb lengthening, achieved correction of preoperative limp, and good functional and radiographic outcomes for 22 Crowe type-IV dislocation hips at the time of the 5- to 10-year follow-up. Copyright © 2016 Elsevier Inc. All rights reserved.

Cytotoxicity of titanium and titanium alloying elements.

PubMed

Li, Y; Wong, C; Xiong, J; Hodgson, P; Wen, C

2010-05-01

It is commonly accepted that titanium and the titanium alloying elements of tantalum, niobium, zirconium, molybdenum, tin, and silicon are biocompatible. However, our research in the development of new titanium alloys for biomedical applications indicated that some titanium alloys containing molybdenum, niobium, and silicon produced by powder metallurgy show a certain degree of cytotoxicity. We hypothesized that the cytotoxicity is linked to the ion release from the metals. To prove this hypothesis, we assessed the cytotoxicity of titanium and titanium alloying elements in both forms of powder and bulk, using osteoblast-like SaOS(2) cells. Results indicated that the metal powders of titanium, niobium, molybdenum, and silicon are cytotoxic, and the bulk metals of silicon and molybdenum also showed cytotoxicity. Meanwhile, we established that the safe ion concentrations (below which the ion concentration is non-toxic) are 8.5, 15.5, 172.0, and 37,000.0 microg/L for molybdenum, titanium, niobium, and silicon, respectively.

Deformation Mechanisms in Tube Billets from Zr-1%Nb Alloy under Radial Forging

NASA Astrophysics Data System (ADS)

Perlovich, Yuriy; Isaenkova, Margarita; Fesenko, Vladimir; Krymskaya, Olga; Zavodchikov, Alexander

2011-05-01

Features of the deformation process by cold radial forging of tube billets from Zr-1%Nb alloy were reconstructed on the basis of X-ray data concerning their structure and texture. The cold radial forging intensifies grain fragmentation in the bulk of billet and increases significantly the latent hardening of potentially active slip systems, so that operation only of the single slip system becomes possible. As a result, in radially-forged billets unusual deformation and recrystallization textures arise. These textures differ from usual textures of α-Zr by the mutual inversion of crystallographic axes, aligned along the axis of tube.

Roosevelt Hot Springs, Utah FORGE Rock Properties

DOE Data Explorer

Gwynn, Mark

2018-04-07

This is an Excel spreadsheet that contains rock properties from several wells in the Utah FORGE study area. This includes a map of the wells. Data is described in the Final Topical Report included in the resources below.

77 FR 39997 - Heavy Forged Hand Tools, Finished or Unfinished, With or Without Handles From the People's...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-06

... DEPARTMENT OF COMMERCE International Trade Administration [A-570-803] Heavy Forged Hand Tools... review on heavy forged hand tools, finished or unfinished, with or without handles from the People's..., 2012) (Tianjin v. United States). \\2\\ See Heavy Forged Hand Tools, Finished or Unfinished, With or...

Fallon FORGE Well Temp data

DOE Data Explorer

Doug Blankenship

2016-03-01

x,y,z downhole temperature data for wells in and around the Fallon FORGE site. Data for the following wells are included: 82-36, 82-19, 84.31, 61-36, 88-24, FOH-3D, FDU-1, and FDU-2. Data are formatted in txt format and in columns for importing into Earthvision Software. Column headers and coordinate system information is stored in the file header.

Does cemented or cementless single-stage exchange arthroplasty of chronic periprosthetic hip infections provide similar infection rates to a two-stage? A systematic review.

PubMed

George, D A; Logoluso, N; Castellini, G; Gianola, S; Scarponi, S; Haddad, F S; Drago, L; Romano, C L

2016-10-10

The best surgical modality for treating chronic periprosthetic hip infections remains controversial, with a lack of randomised controlled studies. The aim of this systematic review is to compare the infection recurrence rate after a single-stage versus a two-stage exchange arthroplasty, and the rate of cemented versus cementless single-stage exchange arthroplasty for chronic periprosthetic hip infections. We searched for eligible studies published up to December 2015. Full text or abstract in English were reviewed. We included studies reporting the infection recurrence rate as the outcome of interest following single- or two-stage exchange arthroplasty, or both, with a minimum follow-up of 12 months. Two reviewers independently abstracted data and appraised quality assessment. After study selection, 90 observational studies were included. The majority of studies were focused on a two-stage hip exchange arthroplasty (65 %), 18 % on a single-stage exchange, and only a 17 % were comparative studies. There was no statistically significant difference between a single-stage versus a two-stage exchange in terms of recurrence of infection in controlled studies (pooled odds ratio of 1.37 [95 % CI = 0.68-2.74, I 2  = 45.5 %]). Similarly, the recurrence infection rate in cementless versus cemented single-stage hip exchanges failed to demonstrate a significant difference, due to the substantial heterogeneity among the studies. Despite the methodological limitations and the heterogeneity between single cohorts studies, if we considered only the available controlled studies no superiority was demonstrated between a single- and two-stage exchange at a minimum of 12 months follow-up. The overalapping of confidence intervals related to single-stage cementless and cemented hip exchanges, showed no superiority of either technique.

Identification of Forged Bank of England 20 Gbp Banknotes Using IR Spectroscopy

NASA Astrophysics Data System (ADS)

Sonnex, Emily

2014-06-01

Bank of England notes of 20 GBP denomination have been studied using infrared spectroscopy in order to generate a method to identify forged notes. A principal aim of this work was to develop a method so that a small, compact ATR FTIR instrument could be used by bank workers, police departments or others such as shop assistants to identify forged notes in a non-lab setting. The ease of use of the instrument is the key to this method, as well as the relatively low cost. The presence of a peak at 1400 wn from the blank paper section of a forged note proved to be a successful indicator of the note's illegality for the notes that we studied. Moreover, differences between the spectra of forged and genuine 20 GBP notes were observed in the ν(OH) (ca. 3500 wn), ν(C-H) (ca. 2900 wn) and ν(C=O) (ca. 1750 wn) regions of the IR spectrum recorded for the polymer film covering the holographic strip. In cases where these simple tests fail, we have shown how an infrared microscope can be used to further differentiate genuine and forged banknotes by producing infrared maps of selected areas of the note contrasting inks with background paper. Further to this, with an announcement by the Bank of England to produce polymer banknotes in the future, the work has been extended using Australian polymer banknotes to show that the method would be transferable.

76 FR 31631 - Heavy Forged Hand Tools From China; Scheduling of Expedited Five-Year Reviews Concerning the...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-01

... INTERNATIONAL TRADE COMMISSION [Investigation Nos. 731-TA-457-A-D Third Review] Heavy Forged Hand... Heavy Forged Hand Tools From China. AGENCY: United States International Trade Commission. ACTION: Notice... the antidumping duty orders on heavy forged hand tools from China would be likely to lead to...

Cell Attachment Following Instrumentation with Titanium and Plastic Instruments, Diode Laser, and Titanium Brush on Titanium, Titanium-Zirconium, and Zirconia Surfaces.

PubMed

Lang, Melissa S; Cerutis, D Roselyn; Miyamoto, Takanari; Nunn, Martha E

2016-01-01

The aim of this study was to evaluate the surface characteristics and gingival fibroblast adhesion of disks composed of implant and abutment materials following brief and repeated instrumentation with instruments commonly used in procedures for implant maintenance, stage-two implant surgery, and periimplantitis treatment. One hundred twenty disks (40 titanium, 40 titaniumzirconium, 40 zirconia) were grouped into treatment categories of instrumentation by plastic curette, titanium curette, diode microlaser, rotary titanium brush, and no treatment. Twenty strokes were applied to half of the disks in the plastic and titanium curette treatment categories, while half of the disks received 100 strokes each to simulate implant maintenance occurring on a repetitive basis. Following analysis of the disks by optical laser profilometry, disks were cultured with human gingival fibroblasts. Cell counts were conducted from scanning electron microscopy (SEM) images. Differences in surface roughness across all instruments tested for zirconia disks were negligible, while both titanium disks and titaniumzirconium disks showed large differences in surface roughness across the spectrum of instruments tested. The rotary titanium brush and the titanium curette yielded the greatest overall mean surface roughness, while the plastic curette yielded the lowest mean surface roughness. The greatest mean cell counts for each disk type were as follows: titanium disks with plastic curettes, titanium-zirconium disks with titanium curettes, and zirconia disks with the diode microlaser. Repeated instrumentation did not result in cumulative changes in surface roughness of implant materials made of titanium, titanium-zirconium, or zirconia. Instrumentation with plastic implant curettes on titanium and zirconia surfaces appeared to be more favorable than titanium implant curettes in terms of gingival fibroblast attachment on these surfaces.

Preparation of the femoral bone cavity in cementless stems: broaching versus compaction

PubMed Central

Hjorth, Mette H; Stilling, Maiken; Søballe, Kjeld; Nielsen, Poul Torben; Christensen, Poul H; Kold, Søren

2016-01-01

Background and purpose — Short-term experimental studies have confirmed that there is superior fixation of cementless implants inserted with compaction compared to broaching of the cancellous bone. Patients and methods — 1-stage, bilateral primary THA was performed in 28 patients between May 2001 and September 2007. The patients were randomized to femoral bone preparation with broaching on 1 side and compaction on the other side. 8 patients declined to attend the postoperative follow-up, leaving 20 patients (13 male) with a mean age of 58 (36–70) years for evaluation. The patients were followed with radiostereometric analysis (RSA) at baseline, at 6 and 12 weeks, and at 1, 2, and 5 years, and measurements of periprosthetic bone mineral density (BMD) at baseline and at 1, 2, and 5 years. The subjective part of the Harris hip score (HHS) and details of complications throughout the observation period were obtained at a mean interval of 6.3 (3.0–9.5) years after surgery. Results — Femoral stems in the compaction group had a higher degree of medio-lateral migration (0.21 mm, 95% CI: 0.03–0.40) than femoral stems in the broaching group at 5 years (p = 0.02). No other significant differences in translations or rotations were found between the 2 surgical techniques at 2 years (p > 0.4) and 5 years (p > 0.7) postoperatively. There were no individual stems with continuous migration. Periprosthetic BMD in the 7 Gruen zones was similar at 2 years and at 5 years. Intraoperative femoral fractures occurred in 2 of 20 compacted hips, but there were none in the 20 broached hips. The HHS and dislocations were similar in the 2 groups at 6.3 (3.0–9.5) years after surgery. Interpretation — Bone compaction as a surgical technique with the Bi-Metric stem did not show the superior outcomes expected compared to conventional broaching. Furthermore, 2 periprosthetic fractures occurred using the compaction technique, so we cannot recommend compaction for insertion of the

The Proximal and Distal Femoral Canal Geometry Influences Cementless Stem Anchorage and Revision Hip and Knee Implant Stability.

PubMed

Heinecke, Markus; Rathje, Fabian; Layher, Frank; Matziolis, Georg

2018-05-01

Although cementless revision arthroplasty of the hip has become the gold standard, revision arthroplasty of the distal femur is controversial. This study evaluated the anchoring principles of different femoral revision stem designs in extended bone defect situations, taking into account the anatomical conditions of the proximal and distal femur, and the resulting primary stability. Cementless press-fit stems of 4 different designs were implanted in synthetic femurs. The specimens were analyzed by computed tomography and were tested considering axial/torsional stiffness and migration resistance. Different stem designs anchored in different femoral canal geometries achieved comparable primary stability. Despite considerably different anchorage lengths, no difference in migration behavior or stiffness was found. Both in the distal femur and in the proximal femur, the conical stems showed a combination of conical and 3-point anchorage. Regarding the cylindrical stem tested, a much shorter anchorage length was sufficient in the distal femur to achieve comparable primary stability. In the investigated osseous defect model, the stem design (conical vs cylindrical), not the geometry of the femoral canal (proximal vs distal), was decisive regarding the circumferential anchorage length. For the conical stems, it can be postulated that there are reserves available for achieving a conical-circular fixation as a result of the large contact length. For the cylindrical stems, only a small reserve for a stable anchorage can be assumed. [Orthopedics. 2018; 41(3):e369-e375.]. Copyright 2018, SLACK Incorporated.

2016 Accomplishments. Tritium aging studies on stainless steel. Forging process effects on the fracture toughness properties of tritium-precharged stainless steel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morgan, Michael J.

Forged austenitic stainless steels are used as the materials of construction for pressure vessels designed to contain tritium at high pressure. These steels are highly resistant to tritium-assisted fracture but their resistance can depend on the details of the forging microstructure. During FY16, the effects of forging strain rate and deformation temperature on the fracture toughness properties of tritium-exposed-and-aged Type 304L stainless steel were studied. Forgings were produced from a single heat of steel using four types of production forging equipment – hydraulic press, mechanical press, screw press, and high-energy-rate forging (HERF). Each machine imparted a different nominal strain ratemore » during the deformation. The objective of the study was to characterize the J-Integral fracture toughness properties as a function of the industrial strain rate and temperature. The second objective was to measure the effects of tritium and decay helium on toughness. Tritium and decay helium effects were measured by thermally precharging the as-forged specimens with tritium gas at 34.5 MPa and 350°C and aging for up to five years at -80°C to build-in decay helium prior to testing. The results of this study show that the fracture toughness properties of the as-forged steels vary with forging strain rate and forging temperature. The effect is largely due to yield strength as the higher-strength forgings had the lower toughness values. For non-charged specimens, fracture toughness properties were improved by forging at 871°C versus 816°C and Screw-Press forgings tended to have lower fracture toughness values than the other forgings. Tritium exposures reduced the fracture toughness values remarkably to fracture toughness values averaging 10-20% of as-forged values. However, forging strain rate and temperature had little or no effect on the fracture toughness after tritium precharging and aging. The result was confirmed by fractography which indicated that

Vanadium release in whole blood, serum and urine of patients implanted with a titanium alloy hip prosthesis.

PubMed

Catalani, S; Stea, S; Beraudi, A; Gilberti, M E; Bordini, B; Toni, A; Apostoli, P

2013-08-01

Vanadium (V) is a minor constituent of the Titanium-Aluminum-Vanadium (TiAlV) alloy currently used in cementless hip prostheses. Present study aimed at verifying the correlation of vanadium levels among different matrices and assessing reference levels of the ion in a population of patients wearing a well-functioning hip prosthesis. Vanadium was measured using Inductive Coupled Plasma Mass Spectrometry (ICP-MS) in whole blood, serum and urine of 129 patients implanted with a TiAlV-alloy hip prosthesis. The values in the serum were above the upper limit of the reference values in 42% of patients (29% in urine and 13% in whole blood). A good correlation among matrices was observed (p < 0.001). The cohort of patients (N = 32) complaining of pain or in which a loosening or damage to the prosthesis was assessed showed a significantly higher excretion of vanadium in urine as compared with the remaining asymptomatic patients (p = 0.001). The 95th percentile distribution of vanadium in the cohort of patients with a well-functioning prosthesis was 0.3 μg/L in whole blood, 0.5 μg/L in serum and 2.8 μg/L in urine, higher that in the unexposed population, especially for urine. The presence of a prosthesis, even though well-functioning, may cause a possible release of vanadium into the blood and a significant urinary excretion. The reference values of vanadium of the asymptomatic patients with titanium alloy hip prostheses supplied information regarding the background exposure level of the ions and their lower and upper limits.

Netcast™ Shape Casting Technology: A Technological Breakthrough that Enhances the Cost Effectiveness of Aluminum Forgings

NASA Astrophysics Data System (ADS)

Anderson, Mark; Bruski, Richard; Groszkiewicz, Daniel; Wagstaff, Bob

A new Direct Chill (DC) casting process is introduced to semi-continuous casting where near net shaped ingots are solidified. This process is currently being used at Alcan Engineered Cast Products (ECP) facility in Jonquiere, Canada, sectioned, then forged at Alcoa Automotive, Kentucky Casting Center (KCC). Finished forgings are machined and assembled into the Ford D/EW98 platform as suspension components. A brief description of the process and the implications on the forging process are presented.

[A method of temperature measurement for hot forging with surface oxide based on infrared spectroscopy].

PubMed

Zhang, Yu-cun; Qi, Yan-de; Fu, Xian-bin

2012-05-01

High temperature large forging is covered with a thick oxide during forging. It leads to a big measurement data error. In this paper, a method of measuring temperature based on infrared spectroscopy is presented. It can effectively eliminate the influence of surface oxide on the measurement of temperature. The method can measure the surface temperature and emissivity of the oxide directly using the infrared spectrum. The infrared spectrum is radiated from surface oxide of forging. Then it can derive the real temperature of hot forging covered with the oxide using the heat exchange equation. In order to greatly restrain interference spectroscopy through included in the received infrared radiation spectrum, three interference filter system was proposed, and a group of optimal gap parameter values using spectral simulation were obtained. The precision of temperature measurement was improved. The experimental results show that the method can accurately measure the surface temperature of high temperature forging covered with oxide. It meets the requirements of measurement accuracy, and the temperature measurement method is feasible according to the experiment result.

75 FR 70689 - Kaiser Aluminum Fabricated Products, LLC; Kaiser Aluminum-Greenwood Forge Division; Currently...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-18

... Fabricated Products, LLC; Kaiser Aluminum- Greenwood Forge Division; Currently Known As Contech Forgings, LLC..., South Carolina; Amended Certification Regarding Eligibility To Apply or Worker Adjustment Assistance In... Labor issued a Certification of Eligibility to Apply for Worker Adjustment Assistance on October 2, 2009...

Preparation of the Femoral Bone Cavity for Cementless Stems: Broaching vs Compaction. A Five-Year Randomized Radiostereometric Analysis and Dual Energy X-Ray Absorption Study.

PubMed

Hjorth, Mette H; Kold, Søren; Søballe, Kjeld; Langdahl, Bente L; Nielsen, Poul T; Christensen, Poul H; Stilling, Maiken

2017-06-01

Short-term experimental and animal studies have confirmed superior fixation of cementless implants inserted with compaction compared to broaching of the cancellous bone. Forty-four hips in 42 patients (19 men) were randomly operated using cementless hydroxyapatite-coated Bi-Metric stems. Patients were followed with radiostereometric analysis at baseline, 6 and 12 weeks, 1, 2, and 5 years, and measurements of periprosthetic bone mineral density at baseline, 1, 2, and 5 years. Complications during the study period and clinical outcome measures of Harris Hip Score were recorded at mean 7 years (5-8.8) after surgery. Absolute migrations of medio/lateral translations between the broaching group and the compaction group of mean 0.14 mm (standard deviation [SD] 0.10) vs mean 0.30 mm (SD 0.27) (P = .01) at 1 year, and of mean 0.13 mm (SD 0.10) vs 0.34 mm (0.31) (P = .01) at 5 years were different. Absolute valgus/varus rotations of mean 0.12° (SD 0.13°) in the broaching group were less than mean 0.35° (0.45°) in the compaction group (P < .01) at 1 year, but at 5 years no difference was observed (P = .19). Subsidence and retroversion were similar between groups at all follow-ups (P > .13). The compaction group had significantly less bone loss than the broaching group in Gruen zone 3 (distal-lateral to the stem) at 1 and 5 years. No further differences in bone mineral density changes were found between groups up to 5 years after surgery. Complications throughout the period and clinical outcome measures of Harris Hip Score were similar at 7 years (5-8.8) after surgery. We found increased migration when preparing the bone with compaction compared with broaching in cementless femoral stems. Copyright © 2017 Elsevier Inc. All rights reserved.

Forging Inclusive Solutions: Experiential Earth Charter Education

ERIC Educational Resources Information Center

Hill, Linda D.

2010-01-01

Forging Inclusive Solutions describes the aims, methodology and outcomes of Inclusive Leadership Adventures, an experiential education curriculum for exploring the Earth Charter. Experiential education builds meaningful relationships, skills, awareness and an inclusive community based on the Earth Charter principles. When we meet people where they…

Development and installation of an advanced beam guidance system on Viking`s 2.4 megawatt EB furnace

DOE Office of Scientific and Technical Information (OSTI.GOV)

Motchenbacher, C.A.; Grosse, I.A.

1994-12-31

Viking Metallurgical is a manufacturer of titanium alloy and superalloy seamless ring forgings for the aerospace industry. For more than 20 years Viking has used electron beam cold hearth melting to recover titanium alloy scrap and to produce commercially pure titanium ingot for direct forging. In the 1970`s Viking pioneered electron beam cold hearth melting and in 1983 added a two-gun, 2.4 MW furnace. As part of Vikings efforts to improve process control we have commissioned and installed a new electron beam guidance system. The system is capable of generating virtually unlimited EB patterns resulting in improved melt control.

Inter- and intra-observer variability of radiography and computed tomography for evaluation of Zurich cementless acetabular cup placement ex vivo.

PubMed

Leasure, Jessica O; Peck, Jeffrey N; Villamil, Armando; Fiore, Kara L; Tano, Cheryl A

2016-11-23

To evaluate the inter- and intra-observer variability in measurement of the angle of lateral opening (ALO) and version angle measurement using digital radiography and computed tomography (CT). Each hemipelvis was implanted with a cementless acetabular cup. Ventrodorsal and mediolateral radiographs were made of each pelvis, followed by CT imaging. After removal of the first cup, the pelves were implanted with an acetabular cup in the contralateral acetabulum and imaging was repeated. Three surgeons measured the ALO and version angles three times for each cup from the mediolateral radiographic projection. The same measurements were made using three-dimensional multiplanar reconstructions from CT images. Two anatomical axes were used to measure pelvic inclination in the sagittal plane, resulting in six measurements per cup. Two-way repeated measures analysis of variance evaluated inter- and intra-observer repeatability for radiographic and CT-based measurements. Version angle based on radiographic measurement did not differ within surgeons (p = 0.433), but differed between surgeons (p <0.001). Radiographic measurement of ALO differed within surgeons (p = 0.006) but not between surgeons (p = 0.989). The ALO and version angle measured on CT images did not differ with or between surgeons. Assessment of inter- and intra-observer measurement of ALO and version angle was more reproducible using CT images than conventional mediolateral radiography for a Zurich cementless acetabular cup.

Microstructure and degradation behavior of forged Fe-Mn-Si alloys

NASA Astrophysics Data System (ADS)

Xu, Zhigang; Hodgson, Michael A.; Cao, Peng

2015-03-01

This work presents a comparative study of a series of Fe-Mn-Si alloys proposed as degradable biomaterials for medical applications. Five Fe-28wt.%Mn-xSi (where x = 0 to 8 wt.%) alloys were fabricated by an arc-melting method. All the as-cast alloys were subsequently subjected to homogenization treatment and hot forging. The microstructure and phase constituents were investigated. It is found that the grain size of the as-forged alloys ranged approximately from 30 to 50 μm. The as-forged Fe-Mn-Si alloys containing Si from 2 to 6 wt.% was comprised of duplex martensitic ɛ and austenitic γ phases; however, the Si-free and 8 wt.% Si alloys only consisted of a single γ phase. After 30 days of static immersion test in a simulated body fluid (SBF) medium, it is found that pitting and general corrosion occur on the sample surfaces. Potentiodynamic analysis reveals that the degradation rate of the Fe-Mn-Si alloys increased gradually with Si content up to 6 wt.%, beyond which the degradation slows down.

Evaluation of Stress Corrosion Cracking Susceptibility Using Fracture Mechanics Techniques, Part 1. [environmental tests of aluminum alloys, stainless steels, and titanium alloys

NASA Technical Reports Server (NTRS)

Sprowls, D. O.; Shumaker, M. B.; Walsh, J. D.; Coursen, J. W.

1973-01-01

Stress corrosion cracking (SSC) tests were performed on 13 aluminum alloys, 13 precipitation hardening stainless steels, and two titanium 6Al-4V alloy forgings to compare fracture mechanics techniques with the conventional smooth specimen procedures. Commercially fabricated plate and rolled or forged bars 2 to 2.5-in. thick were tested. Exposures were conducted outdoors in a seacoast atmosphere and in an inland industrial atmosphere to relate the accelerated tests with service type environments. With the fracture mechanics technique tests were made chiefly on bolt loaded fatigue precracked compact tension specimens of the type used for plane-strain fracture toughness tests. Additional tests of the aluminum alloy were performed on ring loaded compact tension specimens and on bolt loaded double cantilever beams. For the smooth specimen procedure 0.125-in. dia. tensile specimens were loaded axially in constant deformation type frames. For both aluminum and steel alloys comparative SCC growth rates obtained from tests of precracked specimens provide an additional useful characterization of the SCC behavior of an alloy.

A material based approach to creating wear resistant surfaces for hot forging

NASA Astrophysics Data System (ADS)

Babu, Sailesh

Tools and dies used in metal forming are characterized by extremely high temperatures at the interface, high local pressures and large metal to metal sliding. These harsh conditions result in accelerated wear of tooling. Lubrication of tools, done to improve metal flow drastically quenches the surface layers of the tools and compounds the tool failure problem. This phenomenon becomes a serious issue when parts forged at complex and are expected to meet tight tolerances. Unpredictable and hence uncontrolled wear and degradation of tooling result in poor part quality and premature tool failure that result in high scrap, shop downtime, poor efficiency and high cost. The objective of this dissertation is to develop a computer-based methodology for analyzing the requirements hot forging tooling to resist wear and plastic deformation and wear and predicting life cycle of forge tooling. Development of such is a system is complicated by the fact that wear and degradation of tooling is influenced by not only the die material used but also numerous process controls like lubricant, dilution ratio, forging temperature, equipment used, tool geometries among others. Phenomenological models available u1 the literature give us a good thumb rule to selecting materials but do not provide a way to evaluate pits performance in field. Once a material is chosen, there are no proven approaches to create surfaces out of these materials. Coating approaches like PVD and CVD cannot generate thick coatings necessary to withstand the conditions under hot forging. Welding cannot generate complex surfaces without several secondary operations like heat treating and machining. If careful procedures are not followed, welds crack and seldom survive forging loads. There is a strong need for an approach to selectively, reliably and precisely deposit material of choice reliably on an existing surface which exhibit not only good tribological properties but also good adhesion to the substrate

Effect of raw materials and hardening process on hardness of manually forged knife

NASA Astrophysics Data System (ADS)

Balkhaya, Suwarno

2017-06-01

Knives are normally made by forging process either using a machine or traditional method by means of hammering process. This present work was conducted to study the effects of steel raw materials and hardening process on the hardness of manually forged knives. The knife samples were made by traditional hammering (forging) process done by local blacksmith. Afterward, the samples were heat treated with two different hardening procedures, the first was based on the blacksmith procedure and the second was systematically done at the laboratory. The forging was done in the temperature ranged between 900-950°C, while the final temperature ranged between 650-675°C. The results showed that knives made of spring steel and heat treated in simulated condition at the laboratory obtained higher level of hardness, i.e. 62 HRC. In general, knives heat treated by local blacksmith had lower level of hardness that those obtained from simulated condition. Therefore, we concluded that the traditional knife quality in term of hardness can be improved by optimizing the heat treatment schedule.

Assessment of NASA Dual Microstructure Heat Treatment Method for Multiple Forging Batch Heat Treatment

NASA Technical Reports Server (NTRS)

Gayda, John (Technical Monitor); Lemsky, Joe

2004-01-01

NASA dual microstructure heat treatment technology previously demonstrated on single forging heat treat batches of a generic disk shape was successfully demonstrated on a multiple disk batch of a production shape component. A group of four Rolls-Royce Corporation 3rd Stage AE2100 forgings produced from alloy ME209 were successfully dual microstructure heat treated as a single heat treat batch. The forgings responded uniformly as evidenced by part-to-part consistent thermocouple recordings and resultant macrostructures, and from ultrasonic examination. Multiple disk DMHT processing offers a low cost alternative to other published dual microstructure processing techniques.

Development of an acoustic measurement protocol to monitor acetabular implant fixation in cementless total hip Arthroplasty: A preliminary study.

PubMed

Goossens, Quentin; Leuridan, Steven; Henyš, Petr; Roosen, Jorg; Pastrav, Leonard; Mulier, Michiel; Desmet, Wim; Denis, Kathleen; Vander Sloten, Jos

2017-11-01

In cementless total hip arthroplasty (THA), the initial stability is obtained by press-fitting the implant in the bone to allow osseointegration for a long term secondary stability. However, finding the insertion endpoint that corresponds to a proper initial stability is currently based on the tactile and auditory experiences of the orthopedic surgeon, which can be challenging. This study presents a novel real-time method based on acoustic signals to monitor the acetabular implant fixation in cementless total hip arthroplasty. Twelve acoustic in vitro experiments were performed on three types of bone models; a simple bone block model, an artificial pelvic model and a cadaveric model. A custom made beam was screwed onto the implant which functioned as a sound enhancer and insertor. At each insertion step an acoustic measurement was performed. A significant acoustic resonance frequency shift was observed during the insertion process for the different bone models; 250 Hz (35%, second bending mode) to 180 Hz (13%, fourth bending mode) for the artificial bone block models and 120 Hz (11%, eighth bending mode) for the artificial pelvis model. No significant frequency shift was observed during the cadaveric experiment due to a lack of implant fixation in this model. This novel diagnostic method shows the potential of using acoustic signals to monitor the implant seating during insertion. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

Survival of cementless femoral components after osteonecrosis of the femoral head with different etiologies.

PubMed

Radl, Roman; Egner, Sigrun; Hungerford, Marc; Rehak, Peter; Windhager, Reinhard

2005-06-01

We reviewed 41 patients with 55 cementless total hip arthroplasty operated for advanced osteonecrosis. Patients were divided into 2 groups according to etiology of the osteonecrosis. The first group included 17 cases with osteonecrosis without a systemic disease and the second group 38 cases with osteonecrosis associated with a systemic disease. The follow-up was on average 6.4 years (range, 2-12.8). Eight (15.4%) stem revisions had to be performed; all of them were in the patients with a systemic disease. Ten-year survival rates with femoral revision as the endpoint were in the first group 100% and in the systemic disease group 68% (P = .03). The data of this retrospective study indicate a correlation between the survival of the femoral component and the etiology of the osteonecrosis.

Welded Titanium Case for Space-Probe Rocket Motor

NASA Technical Reports Server (NTRS)

Brothers, A. J.; Boundy, R. A.; Martens, H. E.; Jaffe, L. D.

1959-01-01

components used to make the stainless steel and the 6A1--4V titanium alloy cases. The forward dome and aft fitting for the stainless steel assembly were fabricated from a combination of forged, spun and machined parts.. In order to facilitate the fabrication of the titanium alloy motor ) these components were machined from a large-diameter billet.

Titanium

USGS Publications Warehouse

Bedinger, G.M.

2013-01-01

Titanium is the ninth most abundant element in the earth’s crust and can be found in nearly all rocks and sediments. It is a lithophile element with a strong affinity for oxygen and is not found as a pure metal in nature. Titanium was first isolated as a pure metal in 1910, but it was not until 1948 that metal was produced commercially using the Kroll process (named after its developer, William Kroll) to reduce titanium tetrachloride with magnesium to produce titanium metal.

Initial stability of cementless acetabular cups: press-fit and screw fixation interaction--an in vitro biomechanical study.

PubMed

Tabata, Tomonori; Kaku, Nobuhiro; Hara, Katsutoshi; Tsumura, Hiroshi

2015-04-01

Press-fit and screw fixation are important technical factors to achieve initial stability of a cementless acetabular cup for good clinical results of total hip arthroplasty. However, how these factors affect one another in initial cup fixation remains unclear. Therefore, this study aimed to evaluate the mutual influence between press-fit and screw fixation on initial cup stability. Foam bone was subjected to exact hemispherical-shape machining to diameters of 48, 48.5 and 49 mm. A compressive force was applied to ensure seating of a 48-mm-diameter acetabular cup in the foam bone prior to testing. Screws were inserted in six different conditions and tightened in a radial direction at the same torque strength. Then, the socket was rotated with a twist-testing machine, and the torque value at the start of axial rotation between the socket and the foam bone was measured under each screw condition. The torque values for the 48-mm-diameter reaming were >20 N m higher than those for the 48.5- and 49-mm-diameter reaming in each screw condition, indicating that press-fit fixation is stronger than screw fixation. Meanwhile, torque values for the 48.5- and 49-mm-diameter reaming tended to increase with increasing the number of screws. According to our experiment, press-fit fixation of a cementless acetabular cup achieved rigid stability. Although the supplemental screws increased stability of the implant under good press-fit conditions, they showed little impact on whole-cup stability. In the case of insufficient press-fit fixation, cup stability depends on screw stability and increasing the number of additional screws increases cup stability.

Full-field measurement of micromotion around a cementless femoral stem using micro-CT imaging and radiopaque markers.

PubMed

Malfroy Camine, V; Rüdiger, H A; Pioletti, D P; Terrier, A

2016-12-08

A good primary stability of cementless femoral stems is essential for the long-term success of total hip arthroplasty. Experimental measurement of implant micromotion with linear variable differential transformers is commonly used to assess implant primary stability in pre-clinical testing. But these measurements are often limited to a few distinct points at the interface. New techniques based on micro-computed tomography (micro-CT) have recently been introduced, such as Digital Volume Correlation (DVC) or markers-based approaches. DVC is however limited to measurement around non-metallic implants due to metal-induced imaging artifacts, and markers-based techniques are confined to a small portion of the implant. In this paper, we present a technique based on micro-CT imaging and radiopaque markers to provide the first full-field micromotion measurement at the entire bone-implant interface of a cementless femoral stem implanted in a cadaveric femur. Micromotion was measured during compression and torsion. Over 300 simultaneous measurement points were obtained. Micromotion amplitude ranged from 0 to 24µm in compression and from 0 to 49µm in torsion. Peak micromotion was distal in compression and proximal in torsion. The technique bias was 5.1µm and its repeatability standard deviation was 4µm. The method was thus highly reliable and compared well with results obtained with linear variable differential transformers (LVDTs) reported in the literature. These results indicate that this micro-CT based technique is perfectly relevant to observe local variations in primary stability around metallic implants. Possible applications include pre-clinical testing of implants and validation of patient-specific models for pre-operative planning. Copyright © 2016 Elsevier Ltd. All rights reserved.

Adapted diffusion processes for effective forging dies

NASA Astrophysics Data System (ADS)

Paschke, H.; Nienhaus, A.; Brunotte, K.; Petersen, T.; Siegmund, M.; Lippold, L.; Weber, M.; Mejauschek, M.; Landgraf, P.; Braeuer, G.; Behrens, B.-A.; Lampke, T.

2018-05-01

Hot forging is an effective production method producing safety relevant parts with excellent mechanical properties. The economic efficiency directly depends on the occurring wear of the tools, which limits service lifetime. Several approaches of the presenting research group aim at minimizing the wear caused by interacting mechanical and thermal loads by using enhanced nitriding technology. Thus, by modifying the surface zone layer it is possible to create a resistance against thermal softening provoking plastic deformation and pronounced abrasive wear. As a disadvantage, intensely nitrided surfaces may possibly include the risk of increased crack sensitivity and therefore feature the chipping of material at the treated surface. Recent projects (evaluated in several industrial applications) show the high technological potential of adapted treatments: A first approach evaluated localized treatments by preventing areas from nitrogen diffusion with applied pastes or other coverages. Now, further ideas are to use this principle to structure the surface with differently designed patterns generating smaller ductile zones beneath nitrided ones. The selection of suitable designs is subject to certain geo-metrical requirements though. The intention of this approach is to prevent the formation and propagation of cracks under thermal shock conditions. Analytical characterization methods for crack sensitivity of surface zone layers and an accurate system of testing rigs for thermal shock conditions verified the treatment concepts. Additionally, serial forging tests using adapted testing geometries and finally, tests in the industrial production field were performed. Besides stabilizing the service lifetime and decreasing specific wear mechanisms caused by thermal influences, the crack behavior was influenced positively. This leads to a higher efficiency of the industrial production process and enables higher output in forging campaigns of industrial partners.

Early Experience with a Short, Tapered Titanium Porous Plasma Sprayed Stem with Updated Design.

PubMed

Lombardi, Adolph V; Manocchio, Antonio G; Berend, Keith R; Morris, Michael J; Adams, Joanne B

2018-06-01

Short stem femoral components in primary total hip arthroplasty (THA) have increased in popularity since the advent of minimally invasive surgical techniques. The concept of a short stem is particularly compatible with tapered designs where the goal is to offload forces proximally in the femur. The purpose of this retrospective review was to review our early experience with a short, tapered titanium femoral component with updated design features. Beginning in November 2011 through February 2012, 92 consented patients (93 hips), at a single center, were treated with primary cementless THA using a short stem, tapered femoral component (Taperloc® Complete Microplasty; Zimmer Biomet, Warsaw, Indiana) and were available for review with a minimum two-year follow-up. Mean patient age at surgery was 63.2 years and body mass index (BMI) was 30.8 kg/m2. Mean stem length used was 110.3mm (range, 95-125). Mean follow-up was 4.5 years (2-6). Harris hip scores improved from 52.5 preoperatively to 84.7 at most recent. One stem was revised the same day for periprosthetic fracture. One patient with early infection was treated with single-stage exchange followed by recurrence that was treated successfully with two-stage exchange. A non-healing wound in one patient was treated with incision and debridement. Radiographic assessment demonstrated no evidence of loosening, osteolysis, distal hypertrophy, or pedestal formation in any hip, and all components appeared well fixed and in appropriate alignment. In this series of patients treated with primary THA using a short, tapered titanium porous plasma-sprayed femoral component with updated design features, good results were achieved with a low incidence of complications and revision. No aseptic loosening or osteolysis has occurred. Radiographic assessment was excellent for all patients.

Forging; Heat Treating and Testing; Technically Oriented Industrial Materials and Process 1: 5898.05.

ERIC Educational Resources Information Center

Dade County Public Schools, Miami, FL.

The course provides students with advanced and exploratory experience in the area of plastic deformation of metals and in the changing of the physical characteristics of metals by the controlled application and timed removal of heat. Course content includes goals, specific objectives, safety in forge work, forging tools and equipment, industrial…

Forging a unique nursing partnership with China.

PubMed

Munn, Flavia

2017-07-12

When members of a London nursing faculty forged a learning partnership with a Chinese counterpart they likely did not expect to be discussing the benefits of using Florence Nightingale lamps to decorate hospital walls. But there is nothing ordinary about the collaboration between King's College London and Nanjing Health School.

Forging Oxide-Dispersion-Strengthened Superalloys

NASA Technical Reports Server (NTRS)

Harf, F. H.; Glasgow, T. K.; Moracz, D. J.; Austin, C. M.

1986-01-01

Cladding of mild steel prevents surface cracking when alloy contacts die. Continual need for improvements in properties of alloys capable of withstanding elevated temperatures. Accomplished by using oxide-dispersion-strengthed superalloys such as Inconel Alloy MA 6000. Elevated tensile properties of forged alloy equal those of hot-rolled MA 6000 bar. Stress-rupture properties somewhat lower than those of bar stock but, at 1,100 degrees C, exceed those of strongest commercial single crystal, directionally solidified and conventionally cast superalloys.

Forging an Identity over the Life-Course

ERIC Educational Resources Information Center

Spiteri, Damian

2009-01-01

Using a social constructionist approach, this study explores the self-perceptions of young men who, when at school, were classed as boys with social, emotional and behavioural difficulties (SEBD). The aim is to understand how these perceptions were forged throughout the young men's life-courses resulting in changing self-identities. The study also…

Characterization of large 2219 aluminum alloy hand forgings for the space shuttle solid rocket booster

NASA Technical Reports Server (NTRS)

Brennecke, M. W.

1978-01-01

The mechanical properties, including fracture toughness, and stress corrosion properties of four types of 2219-T852 aluminum alloy hand forgings are presented. Weight of the forgings varied between 450 and 3500 lb at the time of heat treatment and dimensions exceeded the maximum covered in existing specifications. The forgings were destructively tested to develop reliable mechanical property data to replace estimates employed in the design of the Space Shuttle Solid Rocket Booster (SRB) and to establish minimum guaranteed properties for structural refinement and for entry into specification revisions. The report summarizes data required from the forgers and from the SRB Structures contractor.

Evaluation of Subsequent Heat Treatment Routes for Near-β Forged TA15 Ti-Alloy

PubMed Central

Sun, Zhichao; Wu, Huili; Yang, He

2016-01-01

TA15 Ti-alloy is widely used to form key load-bearing components in the aerospace field, where excellent service performance is needed. Near-β forging technology provides an attractive way to form these complicated Ti-alloy components but subsequent heat treatment has a great impact on the final microstructure and mechanical properties. Therefore evaluation and determination of the heat treatment route is of particular significance. In this paper, for the near-β forged TA15 alloy, the formation and evolution of microstructures under different subsequent heat treatment routes (annealing, solution and aging, toughening and strengthening) were studied and the cooling mode after forging was also considered. Then, the type and characteristics of the obtained microstructures were discussed through quantitative metallographic analysis. The corresponding mechanical properties (tensile, impact toughness, and fracture toughness) and effects of microstructural characteristics were investigated. Finally, for a required microstructure and performance a reasonable heat treatment route was recommended. The work is of importance for the application and development of near-β forging technology. PMID:28773994

The results of a proximally-coated cementless femoral component in total hip replacement: a five- to 12-year follow-up.

PubMed

Kim, Y-H

2008-03-01

This study reviewed the results of a cementless anatomical femoral component to give immediate post-operative stability, and with a narrow distal section in order not to contact the femoral cortex in the diaphysis, ensuring exclusively metaphyseal loading. A total of 471 patients (601 hips) who had a total hip replacement between March 1995 and February 2002 were included in the study. There were 297 men and 174 women. The mean age at the time of operation was 52.7 years (28 to 63). Clinical and radiological evaluation were performed at each follow-up. Bone densitometry was carried out on all patients two weeks after operation and at the final follow-up examination. The mean follow-up was 8.8 years (5 to 12). The mean pre-operative Harris hip score was 41 points (16 to 54), which improved to a mean of 96 (68 to 100) at the final follow-up. No patient complained of thigh pain at any stage. No acetabular or femoral osteolysis was observed and no hip required revision for aseptic loosening of either component. Deep infection occurred in two hips (0.3%) which required revision. One hip (0.2%) required revision of the acetabular component for recurrent dislocation. Bone mineral densitometry revealed a minimal bone loss in the proximal femur. This cementless anatomical femoral component with metaphyseal loading but without distal fixation produced satisfactory fixation and encourages proximal femoral loading.

Cementless total hip arthroplasty with ceramic-on-ceramic bearing in patients younger than 45 years with femoral-head osteonecrosis

PubMed Central

Choi, Yoowang; Kim, Jun-Shik

2009-01-01

Despite improvements in the quality of alumina ceramics, osteolysis has been reported anecdotally after total hip arthroplasty (THA) with use of a contemporary alumina-on-alumina ceramic bearing. The purpose of this study was to evaluate the clinical and radiographic outcomes of THA using alumina-on-alumina ceramic bearing and to determine osteolysis using radiographs and computed tomographic (CT) scans in young patients. Consecutive primary cementless THA using alumina-on-alumina ceramic bearing were performed in 64 patients (93 hips) who were younger than 45 years of age with femoral-head osteonecrosis. There were 55 men (84 hips) and nine women (nine hips). Average age was 38.2 (range 24–45) years. Average follow-up was 11.1 (range 10–13) years. Preoperative Harris Hip Score was 52.9 (range 22–58) points, which improved to 96 (range 85−100) points at the final follow-up examination. Two of 93 hips (2%) had clicking or squeaking sound. No hip had revision or aseptic loosening. Radiographs and CT scans demonstrated that no acetabular or femoral osteolysis was detected in any hip at the latest follow-up. Contemporary cementless acetabular and femoral components with alumina-on-alumina ceramic bearing couples function well with no osteolysis at a ten year minimum and average of 11.1-year follow-up in this series of young patients with femoral-head osteonecrosis. PMID:19784647

Phased array inspection of large size forged steel parts

NASA Astrophysics Data System (ADS)

Dupont-Marillia, Frederic; Jahazi, Mohammad; Belanger, Pierre

2018-04-01

High strength forged steel requires uncompromising quality to warrant advance performance for numerous critical applications. Ultrasonic inspection is commonly used in nondestructive testing to detect cracks and other defects. In steel blocks of relatively small dimensions (at least two directions not exceeding a few centimetres), phased array inspection is a trusted method to generate images of the inside of the blocks and therefore identify and size defects. However, casting of large size forged ingots introduces changes of mechanical parameters such as grain size, the Young's modulus, the Poisson's ratio, and the chemical composition. These heterogeneities affect the wave propagation, and consequently, the reliability of ultrasonic inspection and the imaging capabilities for these blocks. In this context, a custom phased array transducer designed for a 40-ton bainitic forged ingot was investigated. Following a previous study that provided local mechanical parameters for a similar block, two-dimensional simulations were made to compute the optimal transducer parameters including the pitch, width and number of elements. It appeared that depending on the number of elements, backwall reconstruction can generate high amplitude artefacts. Indeed, the large dimensions of the simulated block introduce numerous constructive interferences from backwall reflections which may lead to important artefacts. To increase image quality, the reconstruction algorithm was adapted and promising results were observed and compared with the scattering cone filter method available in the CIVA software.

76 FR 31585 - Forged Stainless Steel Flanges From India: Notice of Rescission of Antidumping Duty...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-01

... Flanges From India: Notice of Rescission of Antidumping Duty Administrative Review AGENCY: Import... review of the antidumping duty order on forged stainless steel flanges from India. The period of review... administrative review of the antidumping duty order on forged stainless steel flanges from India. See Antidumping...

Fallon, Nevada FORGE Gravity and Magnetics Data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blankenship, Doug; Witter, Jeff; Carpenter, Thomas

This package contains principal facts for new gravity data collected September - November 2017 in support of the Fallon FORGE project. Also included are rock core density and magnetic susceptibility data for key core intervals, used in modeling 2D and 3D gravity inversions. Individual metadata summaries are provided as .pdf within each attached archive.

Reliability of system for precise cold forging

NASA Astrophysics Data System (ADS)

Krušič, Vid; Rodič, Tomaž

2017-07-01

The influence of scatter of principal input parameters of the forging system on the dimensional accuracy of product and on the tool life for closed-die forging process is presented in this paper. Scatter of the essential input parameters for the closed-die upsetting process was adjusted to the maximal values that enabled the reliable production of a dimensionally accurate product at optimal tool life. An operating window was created in which exists the maximal scatter of principal input parameters for the closed-die upsetting process that still ensures the desired dimensional accuracy of the product and the optimal tool life. Application of the adjustment of the process input parameters is shown on the example of making an inner race of homokinetic joint from mass production. High productivity in manufacture of elements by cold massive extrusion is often achieved by multiple forming operations that are performed simultaneously on the same press. By redesigning the time sequences of forming operations at multistage forming process of starter barrel during the working stroke the course of the resultant force is optimized.

Making randomised trials more efficient: report of the first meeting to discuss the Trial Forge platform.

PubMed

Treweek, Shaun; Altman, Doug G; Bower, Peter; Campbell, Marion; Chalmers, Iain; Cotton, Seonaidh; Craig, Peter; Crosby, David; Davidson, Peter; Devane, Declan; Duley, Lelia; Dunn, Janet; Elbourne, Diana; Farrell, Barbara; Gamble, Carrol; Gillies, Katie; Hood, Kerry; Lang, Trudie; Littleford, Roberta; Loudon, Kirsty; McDonald, Alison; McPherson, Gladys; Nelson, Annmarie; Norrie, John; Ramsay, Craig; Sandercock, Peter; Shanahan, Daniel R; Summerskill, William; Sydes, Matt; Williamson, Paula; Clarke, Mike

2015-06-05

Randomised trials are at the heart of evidence-based healthcare, but the methods and infrastructure for conducting these sometimes complex studies are largely evidence free. Trial Forge ( www.trialforge.org ) is an initiative that aims to increase the evidence base for trial decision making and, in doing so, to improve trial efficiency.This paper summarises a one-day workshop held in Edinburgh on 10 July 2014 to discuss Trial Forge and how to advance this initiative. We first outline the problem of inefficiency in randomised trials and go on to describe Trial Forge. We present participants' views on the processes in the life of a randomised trial that should be covered by Trial Forge.General support existed at the workshop for the Trial Forge approach to increase the evidence base for making randomised trial decisions and for improving trial efficiency. Agreed upon key processes included choosing the right research question; logistical planning for delivery, training of staff, recruitment, and retention; data management and dissemination; and close down. The process of linking to existing initiatives where possible was considered crucial. Trial Forge will not be a guideline or a checklist but a 'go to' website for research on randomised trials methods, with a linked programme of applied methodology research, coupled to an effective evidence-dissemination process. Moreover, it will support an informal network of interested trialists who meet virtually (online) and occasionally in person to build capacity and knowledge in the design and conduct of efficient randomised trials.Some of the resources invested in randomised trials are wasted because of limited evidence upon which to base many aspects of design, conduct, analysis, and reporting of clinical trials. Trial Forge will help to address this lack of evidence.

Superplastic forging nitride ceramics

DOEpatents

Panda, P.C.; Seydel, E.R.; Raj, R.

1988-03-22

A process is disclosed for preparing silicon nitride ceramic parts which are relatively flaw free and which need little or no machining, said process comprising the steps of: (a) preparing a starting powder by wet or dry mixing ingredients comprising by weight from about 70% to about 99% silicon nitride, from about 1% to about 30% of liquid phase forming additive and from 1% to about 7% free silicon; (b) cold pressing to obtain a preform of green density ranging from about 30% to about 75% of theoretical density; (c) sintering at atmospheric pressure in a nitrogen atmosphere at a temperature ranging from about 1,400 C to about 2,200 C to obtain a density which ranges from about 50% to about 100% of theoretical density and which is higher than said preform green density, and (d) press forging workpiece resulting from step (c) by isothermally uniaxially pressing said workpiece in an open die without initial contact between said workpiece and die wall perpendicular to the direction of pressing and so that pressed workpiece does not contact die wall perpendicular to the direction of pressing, to substantially final shape in a nitrogen atmosphere utilizing a temperature within the range of from about 1,400 C to essentially 1,750 C and strain rate within the range of about 10[sup [minus]7] to about 10[sup [minus]1] seconds[sup [minus]1], the temperature and strain rate being such that surface cracks do not occur, said pressing being carried out to obtain a shear deformation greater than 30% whereby superplastic forging is effected.

Roosevelt Hot Springs, Utah FORGE Observation Well Data

DOE Data Explorer

Nash, Greg

2018-02-22

This archive contains temperature data for Roosevelt Hot Springs observation wells OH-1, OH-4, OH-5 and OH-7. There are also mud logs for OH-4. These are old datasets obtained from Rocky Mountain Power for use in the Utah FORGE project.

Queen City Forging Revitalized by Oak Ridge National Lab Partnership – U.S. Department of Energy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mayer, Rob; Blue, Craig

Oak Ridge National Laboratory, with support from the U.S. Department of Energy, teamed up with Queen City Forging, the U.S. Forging Industry, and Infrared Heating Technologies to develop a rapid-infrared heating furnace to produce aluminum turbochargers.

The effects of composition and thermal path on hot ductility of forging steels

NASA Astrophysics Data System (ADS)

Connolly, Brendan M.

This work examines the effects of composition and thermal path on the hot ductility of several forging steels with varied aluminum and nitrogen content. The primary mechanisms and controlling factors related to hot ductility are identified with a focus on the role of precipitates and segregation. The unique thermal paths and solidification structures of large cross-section forging ingots are discussed. Hot ductility testing is performed in a manner that approximates industrial conditions experienced by large cross-section forging ingots. A computer model for precipitation of aluminum nitride and vanadium nitride in austenite is presented. Industrial material is examined for comparison to experimental findings. It is found that increased aluminum and nitrogen content coarsens the as-solidified structure. The combined effects of microsegregation and uphill diffusion during deformation allow for carbide precipitation at prior austenite grain boundaries which reduces the hot ductility.

Cold forging and chemical heat treatment of the casing of the internal joint for VAZ cars

NASA Astrophysics Data System (ADS)

Arzamastsev, V. A.; Sardaev, N. L.; Kochergin, A. S.

1996-11-01

The technological process of cold forging applied for the first time in the production of the casing of the internal joint with races is described. The process operations of cold forging and the annealing and carburizing regimes for this part me described.

Geologic setting of the proposed Fallon FORGE Site, Nevada: Suitability for EGS research and development

USGS Publications Warehouse

Faulds, James E.; Blankenship, Douglas; Hinz, Nicholas H.; Sabin, Andrew; Nordquist, Josh; Hickman, Stephen H.; Glen, Jonathan; Kennedy, Mack; Siler, Drew; Robinson-Tait, Ann; Williams, Colin F.; Drakos, Peter; Calvin, Wendy M.

2015-01-01

The proposed Fallon FORGE site lies within and adjacent to the Naval Air Station Fallon (NASF) directly southeast of the town of Fallon, Nevada, within the large basin of the Carson Sink in west-central Nevada. The site is located on two parcels that include land owned by the NASF and leased and owned by Ormat Nevada, Inc. The Carson Sink in the vicinity of the Fallon site is covered by Quaternary deposits, including alluvial fan, eolian, and lacustrine sediments. Four wells penetrate the entire Neogene section and bottom in Mesozoic basement. Late Miocene to Quaternary basin-fill sediments are 0.5 to >1 km thick and overlie Oligocene-Miocene volcanic and lesser sedimentary rocks. The volcanic section is 0.5 to 1.0 km thick and dominated by Miocene mafic lavas. The Neogene section rests nonconformably on heterogeneous Mesozoic basement, which consists of Triassic-Jurassic metamorphic rocks intruded by Cretaceous granitic plutons. The structural framework is dominated by a gently west-tilted half graben cut by moderately to steeply dipping N- to NNEstriking normal faults that dip both east and west. Quaternary faults have not been observed within the proposed FORGE site. Fallon was selected for a potential FORGE site due to its extensional tectonic setting, abundance of available data, existing infrastructure, and documented temperatures, permeability, and lithologic composition of potential reservoirs that fall within the ranges specified by DOE for FORGE. Since the early 1970s, more than 45 wells have been drilled for geothermal exploration within the area. Four exploration wells within the FORGE site are available for use in the project. Several additional wells are available for monitoring outside the central FORGE site within the NASF and Ormat lease area, including numerous temperature gradient holes. There is an existing, ten-station micro-seismic earthquake (MEQ) array that has been collecting data since 2001; the MEQ array can be expanded to encompass the

Strain Evolution in Cold-Warm Forged Steel Components Studied by Means of EBSD Technique

PubMed Central

Bonollo, Franco; Bassan, Fabio; Berto, Filippo

2017-01-01

Electron BackScatter Diffraction (EBSD) in conjunction with Field-Emission Environmental Scanning Electron Microscopy (FEG-ESEM) has been used to evaluate the microstructural and local plastic strain evolution in different alloys (AISI 1005, AISI 304L and Duplex 2205) deformed by a single-stage cold and warm forging process. The present work is aimed to describe the different behavior of the austenite and ferrite during plastic deformation as a function of different forging temperatures. Several topological EBSD maps have been measured on the deformed and undeformed states. Then, image quality factor, distributions of the grain size and misorientation have been analyzed in detail. In the austenitic stainless steel, the γ-phase has been found to harden more easily, then α-phase and γ-phase in AISI 1005 and in duplex stainless steel, sequentially. Compared to the high fraction of continuous dynamic recrystallized austenitic zones observed in stainless steels samples forged at low temperatures, the austenitic microstructure of samples forged at higher temperatures, 600–700 °C, has been found to be mainly characterized by large and elongated grains with some colonies of fine nearly-equiaxed grains attributed to discontinuous dynamic recrystallization. PMID:29258249

Numerical modeling of axi-symmetrical cold forging process by ``Pseudo Inverse Approach''

NASA Astrophysics Data System (ADS)

Halouani, A.; Li, Y. M.; Abbes, B.; Guo, Y. Q.

2011-05-01

The incremental approach is widely used for the forging process modeling, it gives good strain and stress estimation, but it is time consuming. A fast Inverse Approach (IA) has been developed for the axi-symmetric cold forging modeling [1-2]. This approach exploits maximum the knowledge of the final part's shape and the assumptions of proportional loading and simplified tool actions make the IA simulation very fast. The IA is proved very useful for the tool design and optimization because of its rapidity and good strain estimation. However, the assumptions mentioned above cannot provide good stress estimation because of neglecting the loading history. A new approach called "Pseudo Inverse Approach" (PIA) was proposed by Batoz, Guo et al.. [3] for the sheet forming modeling, which keeps the IA's advantages but gives good stress estimation by taking into consideration the loading history. Our aim is to adapt the PIA for the cold forging modeling in this paper. The main developments in PIA are resumed as follows: A few intermediate configurations are generated for the given tools' positions to consider the deformation history; the strain increment is calculated by the inverse method between the previous and actual configurations. An incremental algorithm of the plastic integration is used in PIA instead of the total constitutive law used in the IA. An example is used to show the effectiveness and limitations of the PIA for the cold forging process modeling.

Different thermal conductivity in drilling of cemented compared with cementless hip prostheses in the treatment of periprosthetic fractures of the proximal femur: an experimental biomechanical analysis.

PubMed

Brand, Stephan; Klotz, Johannes; Hassel, Thomas; Petri, Maximilian; Ettinger, Max; Krettek, Christian; Goesling, Thomas; Bach, Friedrich-Wilhelm

2013-10-01

The purpose of this study was to evaluate the different temperature levels whilst drilling cemented and cementless hip prostheses implanted in bovine femora, and to evaluate the insulating function of the cement layer. Standard hip prostheses were implanted in bovine donor diaphyses, with or without a cement layer. Drilling was then performed using high-performance-cutting drills with a reinforced core, a drilling diameter of 5.5 mm and cooling channels through the tip of the drill for constantly applied internal cooling solution. An open type cooling model was used in this setup. Temperature was continuously measured by seven thermocouples placed around the borehole. Thermographic scans were also performed during drilling. At the cemented implant surface, the temperature never surpassed 24.7 °C when constantly applied internal cooling was used. Without the insulating cement layer (i.e. during drilling of the cementless bone-prosthesis construct), the temperature increased to 47 °C. Constantly applied internal cooling can avoid structural bone and soft tissue damage during drilling procedures. With a cement layer, the temperatures only increased to non-damaging levels. The results could be useful in the treatment of periprosthetic fractures with intraprosthetic implant fixation.

HaploForge: a comprehensive pedigree drawing and haplotype visualization web application.

PubMed

Tekman, Mehmet; Medlar, Alan; Mozere, Monika; Kleta, Robert; Stanescu, Horia

2017-12-15

Haplotype reconstruction is an important tool for understanding the aetiology of human disease. Haplotyping infers the most likely phase of observed genotypes conditional on constraints imposed by the genotypes of other pedigree members. The results of haplotype reconstruction, when visualized appropriately, show which alleles are identical by descent despite the presence of untyped individuals. When used in concert with linkage analysis, haplotyping can help delineate a locus of interest and provide a succinct explanation for the transmission of the trait locus. Unfortunately, the design choices made by existing haplotype visualization programs do not scale to large numbers of markers. Indeed, following haplotypes from generation to generation requires excessive scrolling back and forth. In addition, the most widely used program for haplotype visualization produces inconsistent recombination artefacts for the X chromosome. To resolve these issues, we developed HaploForge, a novel web application for haplotype visualization and pedigree drawing. HaploForge takes advantage of HTML5 to be fast, portable and avoid the need for local installation. It can accurately visualize autosomal and X-linked haplotypes from both outbred and consanguineous pedigrees. Haplotypes are coloured based on identity by descent using a novel A* search algorithm and we provide a flexible viewing mode to aid visual inspection. HaploForge can currently process haplotype reconstruction output from Allegro, GeneHunter, Merlin and Simwalk. HaploForge is licensed under GPLv3 and is hosted and maintained via GitHub. https://github.com/mtekman/haploforge. r.kleta@ucl.ac.uk. Supplementary data are available at Bioinformatics online. © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Performance Assessment Method for a Forged Fingerprint Detection Algorithm

NASA Astrophysics Data System (ADS)

Shin, Yong Nyuo; Jun, In-Kyung; Kim, Hyun; Shin, Woochang

The threat of invasion of privacy and of the illegal appropriation of information both increase with the expansion of the biometrics service environment to open systems. However, while certificates or smart cards can easily be cancelled and reissued if found to be missing, there is no way to recover the unique biometric information of an individual following a security breach. With the recognition that this threat factor may disrupt the large-scale civil service operations approaching implementation, such as electronic ID cards and e-Government systems, many agencies and vendors around the world continue to develop forged fingerprint detection technology, but no objective performance assessment method has, to date, been reported. Therefore, in this paper, we propose a methodology designed to evaluate the objective performance of the forged fingerprint detection technology that is currently attracting a great deal of attention.

A Life Study of Ausforged, Standard Forged and Standard Machined AISI M-50 Spur Gears

NASA Technical Reports Server (NTRS)

Townsend, D. P.; Bamberger, E. N.; Zaretsky, E. V.

1975-01-01

Tests were conducted at 350 K (170 F) with three groups of 8.9 cm (3.5 in.) pitch diameter spur gears made of vacuum induction melted (VIM) consumable-electrode vacuum-arc melted (VAR), AISI M-50 steel and one group of vacuum-arc remelted (VAR) AISI 9310 steel. The pitting fatigue life of the standard forged and ausforged gears was approximately five times that of the VAR AISI 9310 gears and ten times that of the bending fatigue life of the standard machined VIM-VAR AISI M-50 gears run under identical conditions. There was a slight decrease in the 10-percent life of the ausforged gears from that for the standard forged gears, but the difference is not statistically significant. The standard machined gears failed primarily by gear tooth fracture while the forged and ausforged VIM-VAR AISI M-50 and the VAR AISI 9310 gears failed primarily by surface pitting fatigue. The ausforged gears had a slightly greater tendency to fail by tooth fracture than the standard forged gears.

Utilization of gas-atomized titanium and titanium-aluminide powder

NASA Astrophysics Data System (ADS)

Moll, John H.

2000-05-01

A gas-atomization process has been developed producing clean, high-quality, prealloyed spherical titanium and titanium-aluminide powder. The powder is being used to manufacture hot-isostatically pressed consolidated shapes for aerospace and nonaerospace allocations. These include gamma titanium-aluminide sheet and orthorhombic titanium-aluminide wire as well as niche markets, such as x-ray drift standards and sputtering targets. The powder is also being used in specialized processes, including metal-matrix composites, laser forming, and metal-injection molding.

[The incidence of osteopenia and osteoporosis in patients with cementless total hip arthroplasty].

PubMed

Lacko, M; Schreierová, D; Čellár, R; Vaško, G

2015-01-01

The aim of the study was to evaluate the incidence of osteopenia and osteoporosis in the patients elected to cementless total hip replacement. The group evaluated comprised 100 patients with primary or secondary forms of coxarthrosis who underwent cementless total hip arthroplasty (THA). The results of densitometric examination of the lumbar spine and proximal femur were analysed. Based on the lowest T-score value, the patients were divided into three groups, i.e., fist, normal bone density; second, osteopenia; third, osteoporosis. Clinical examination included patient medical history, Harris hip scores and visual analogue scale assessment for pain intensity; the Kellgren-Lawrence classification was used to measure the grade of hip osteoarthritis; blood tests were made to assess the levels of total calcium, ionised calcium, phosphorus, vitamin D and the markers of bone resorption and formation. Osteoporosis was found in 32 and osteopenia in 21 patients; 47 patients had normal bone density. Osteoporosis was detected in the lumbar spine of 21 patients, in the proximal femur of nine patients and at both sites in two patients. In 13 patients this diagnosis was made for the fist time. The patients with osteoporosis had a significantly lower body mass index. There were no differences in the other characteristics, i.e., age, functional, radiological and laboratory findings, among the groups; all three showed the mean vitamin D concentration below the lowest level of its physiological range. Insufficient vitamin D levels were found in 54 women and 18 men. Of all patients, only 13 women and four men took vitamin D supplements. DISCUSSION Osteoarthritis and osteoporosis are the most frequent complex musculoskeletal diseases. Several studies have suggested that these disorders are mutually exclusive. This assumption has been based on the absence of radiographic evidence of osteoarthritis seen in many elderly patients with femoral neck fractures. Our relatively frequent

Bilaterally Primary Cementless Total Hip Arthroplasty for Severe Hip Ankylosis with Ankylosing Spondylitis.

PubMed

Feng, Dong-Xu; Zhang, Kun; Zhang, Yu-Min; Nian, Yue-Wen; Zhang, Jun; Kang, Xiao-Min; Wu, Shu-Fang; Zhu, Yang-Jun

2016-08-01

Total hip arthroplasty is a reliable therapeutic intervention in patients with ankylosing spondylitis, in whom the aims of surgery are to reduce pain, restore hip function and improve quality of life. The current study is a retrospective analysis of the clinical and radiographic findings in a consecutive series of patients with hip ankylosis associated with severe ankylosing spondylitis who underwent bilateral primary total hip arthroplasty using non-cemented components. From June 2008 to May 2012, total hip arthroplasty was performed on 34 hips in 17 patients with bilateral ankylosis caused by ankylosing spondylitis. The study patients included 13 men and 4 women with a mean age of 24.2 years. The mean duration of disease was 8.3 years and the average duration of hip involvement was 7.6 years. All patients had severe hip pain and dysfunction with bilateral bony ankylosis and no range of motion preoperatively and all underwent bilateral cementless total hip arthroplasty performed by a single surgeon. Joint pain, range of motion (ROM), and Harris hip scores were assessed to evaluate the postoperative results. At a mean follow-up of 31.7 months, all patients had experienced significant clinical improvement in function, ROM, posture and ambulation. At the final follow-up, the mean postoperative flexion ROM was 134.4° compared with 0° preoperatively. Similar improvements were seen in hip abduction, adduction, internal rotation and external rotation. Postoperatively, 23 hips were completely pain-free, six had only occasional discomfort, three mild to moderate pain and two severe pain. The average Harris Hip Score improved from 23.7 preoperatively to 65.8 postoperatively. No stems had loosened at the final follow-up in any patient, nor had any revision surgery been required. Bilateral severe hip ankylosis in patients with ankylosing spondylitis can be treated with cementless bilateral synchronous total hip arthroplasty, which can greatly improve hip joint function and

Effect of Forging Parameters on Low Cycle Fatigue Behaviour of Al/Basalt Short Fiber Metal Matrix Composites

PubMed Central

Karthigeyan, R.; Ranganath, G.

2013-01-01

This paper deals with metal matrix composites (MMCs) of Al 7075 alloy containing different weight percentage (2.5, 5, 7.5, and 10) basalt short fiber reinforcement and unreinforced matrix alloy. The samples were produced by the permanent stir casting technique. The casting ingots were cut into blanks to be forged in single stage and double stage, using MN press and graphite-based lubricant. The microstructures and fatigue properties of the matrix alloy and MMC samples were investigated in the as cast state and in the single and double stage forging operations. The microstructure results showed that the forged sample had a uniform distribution of the basalt short fiber throughout the specimens. Evaluation of the fatigue properties showed that the forged samples had higher values than those of the as cast counterparts. After forging, the enhancement of the fatigue strength of the matrix alloy was so significant and high in the case of 2.5 and 5.0 wt. percentage basalt short fiber reinforced MMC, and there was no enhancement in 7.5 and 10 weight percentages short fiber reinforced MMCs. The fracture damage was mainly due to decohesion at the matrix-fiber interface. PMID:24298207

Effect of forging parameters on low cycle fatigue behaviour of Al/basalt short fiber metal matrix composites.

PubMed

Karthigeyan, R; Ranganath, G

2013-01-01

This paper deals with metal matrix composites (MMCs) of Al 7075 alloy containing different weight percentage (2.5, 5, 7.5, and 10) basalt short fiber reinforcement and unreinforced matrix alloy. The samples were produced by the permanent stir casting technique. The casting ingots were cut into blanks to be forged in single stage and double stage, using MN press and graphite-based lubricant. The microstructures and fatigue properties of the matrix alloy and MMC samples were investigated in the as cast state and in the single and double stage forging operations. The microstructure results showed that the forged sample had a uniform distribution of the basalt short fiber throughout the specimens. Evaluation of the fatigue properties showed that the forged samples had higher values than those of the as cast counterparts. After forging, the enhancement of the fatigue strength of the matrix alloy was so significant and high in the case of 2.5 and 5.0 wt. percentage basalt short fiber reinforced MMC, and there was no enhancement in 7.5 and 10 weight percentages short fiber reinforced MMCs. The fracture damage was mainly due to decohesion at the matrix-fiber interface.

Titanium 2013

USGS Publications Warehouse

2014-01-01

Titanium is the ninth most abundant element in the earth's crust and can be found in nearly all rocks and sediments. It is a lithophile element with a strong affinity for oxygen and is not found as a pure metal in nature. Titanium was first isolated as a pure metal in 1910, but it was not until 1948 that the metal was produced commercially using the Kroll process (named after its developer, William Kroll) to reduce titanium tetrachloride with magnesium to produce titanium metal.

Evolution of A-Type Macrosegregation in Large Size Steel Ingot After Multistep Forging and Heat Treatment

NASA Astrophysics Data System (ADS)

Loucif, Abdelhalim; Ben Fredj, Emna; Harris, Nathan; Shahriari, Davood; Jahazi, Mohammad; Lapierre-Boire, Louis-Philippe

2018-03-01

A-type macrosegregation refers to the channel chemical heterogeneities that can be formed during solidification in large size steel ingots. In this research, a combination of experiment and simulation was used to study the influence of open die forging parameters on the evolution of A-type macrosegregation patterns during a multistep forging of a 40 metric ton (MT) cast, high-strength steel ingot. Macrosegregation patterns were determined experimentally by macroetch along the longitudinal axis of the forged and heat-treated ingot. Mass spectroscopy, on more than 900 samples, was used to determine the chemical composition map of the entire longitudinal sectioned surface. FORGE NxT 1.1 finite element modeling code was used to predict the effect of forging sequences on the morphology evolution of A-type macrosegregation patterns. For this purpose, grain flow variables were defined and implemented in a large scale finite element modeling code to describe oriented grains and A-type segregation patterns. Examination of the A-type macrosegregation showed four to five parallel continuous channels located nearly symmetrical to the axis of the forged ingot. In some regions, the A-type patterns became curved or obtained a wavy form in contrast to their straight shape in the as-cast state. Mass spectrometry analysis of the main alloying elements (C, Mn, Ni, Cr, Mo, Cu, P, and S) revealed that carbon, manganese, and chromium were the most segregated alloying elements in A-type macrosegregation patterns. The observed differences were analyzed using thermodynamic calculations, which indicated that changes in the chemical composition of the liquid metal can affect the primary solidification mode and the segregation intensity of the alloying elements. Finite element modeling simulation results showed very good agreement with the experimental observations, thereby allowing for the quantification of the influence of temperature and deformation on the evolution of the shape of the

Evolution of A-Type Macrosegregation in Large Size Steel Ingot After Multistep Forging and Heat Treatment

NASA Astrophysics Data System (ADS)

Loucif, Abdelhalim; Ben Fredj, Emna; Harris, Nathan; Shahriari, Davood; Jahazi, Mohammad; Lapierre-Boire, Louis-Philippe

2018-06-01

A-type macrosegregation refers to the channel chemical heterogeneities that can be formed during solidification in large size steel ingots. In this research, a combination of experiment and simulation was used to study the influence of open die forging parameters on the evolution of A-type macrosegregation patterns during a multistep forging of a 40 metric ton (MT) cast, high-strength steel ingot. Macrosegregation patterns were determined experimentally by macroetch along the longitudinal axis of the forged and heat-treated ingot. Mass spectroscopy, on more than 900 samples, was used to determine the chemical composition map of the entire longitudinal sectioned surface. FORGE NxT 1.1 finite element modeling code was used to predict the effect of forging sequences on the morphology evolution of A-type macrosegregation patterns. For this purpose, grain flow variables were defined and implemented in a large scale finite element modeling code to describe oriented grains and A-type segregation patterns. Examination of the A-type macrosegregation showed four to five parallel continuous channels located nearly symmetrical to the axis of the forged ingot. In some regions, the A-type patterns became curved or obtained a wavy form in contrast to their straight shape in the as-cast state. Mass spectrometry analysis of the main alloying elements (C, Mn, Ni, Cr, Mo, Cu, P, and S) revealed that carbon, manganese, and chromium were the most segregated alloying elements in A-type macrosegregation patterns. The observed differences were analyzed using thermodynamic calculations, which indicated that changes in the chemical composition of the liquid metal can affect the primary solidification mode and the segregation intensity of the alloying elements. Finite element modeling simulation results showed very good agreement with the experimental observations, thereby allowing for the quantification of the influence of temperature and deformation on the evolution of the shape of the

Sealing glasses for titanium and titanium alloys

DOEpatents

Brow, R.K.; McCollister, H.L.; Phifer, C.C.; Day, D.E.

1997-07-15

Barium lanthanoborate sealing-glass compositions are provided comprising various combinations (in terms of mole-%) of boron oxide (B{sub 2}O{sub 3}), barium oxide (BaO), lanthanum oxide (La{sub 2}O{sub 3}), and at least one other oxide selected from the group consisting of aluminum oxide (Al{sub 2}O{sub 3}), calcium oxide (CaO), lithium oxide (Li{sub 2}O), sodium oxide (Na{sub 2}O), silicon dioxide (SiO{sub 2}), or titanium dioxide (TiO{sub 2}). These sealing-glass compositions are useful for forming hermetic glass-to-metal seals with titanium and titanium alloys having an improved aqueous durability and favorable sealing characteristics. Examples of the sealing-glass compositions are provided having coefficients of thermal expansion about that of titanium or titanium alloys, and with sealing temperatures less than about 900 C, and generally about 700--800 C. The barium lanthanoborate sealing-glass compositions are useful for components and devices requiring prolonged exposure to moisture or water, and for implanted biomedical devices (e.g. batteries, pacemakers, defibrillators, pumps). 1 fig.

Sealing glasses for titanium and titanium alloys

DOEpatents

Brow, Richard K.; McCollister, Howard L.; Phifer, Carol C.; Day, Delbert E.

1997-01-01

Barium lanthanoborate sealing-glass compositions are provided comprising various combinations (in terms of mole-%) of boron oxide (B.sub.2 O.sub.3), barium oxide (BaO), lanthanum oxide (La.sub.2 O.sub.3), and at least one other oxide selected from the group consisting of aluminum oxide (Al.sub.2 O.sub.3), calcium oxide (CaO), lithium oxide (Li.sub.2 O), sodium oxide (Na.sub.2 O), silicon dioxide (SiO.sub.2), or titanium dioxide (TiO.sub.2). These sealing-glass compositions are useful for forming hermetic glass-to-metal seals with titanium and titanium alloys having an improved aqueous durability and favorable sealing characteristics. Examples of the sealing-glass compositions are provided having coefficients of thermal expansion about that of titanium or titanium alloys, and with sealing temperatures less than about 900.degree. C., and generally about 700.degree.-800.degree. C. The barium lanthanoborate sealing-glass compositions are useful for components and devices requiring prolonged exposure to moisture or water, and for implanted biomedical devices (e.g. batteries, pacemakers, defibrillators, pumps).

Sealing glasses for titanium and titanium alloys

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brow, R.K.; McCollister, H.L.; Phifer, C.C.

1997-07-15

Barium lanthanoborate sealing-glass compositions are provided comprising various combinations (in terms of mole-%) of boron oxide (B{sub 2}O{sub 3}), barium oxide (BaO), lanthanum oxide (La{sub 2}O{sub 3}), and at least one other oxide selected from the group consisting of aluminum oxide (Al{sub 2}O{sub 3}), calcium oxide (CaO), lithium oxide (Li{sub 2}O), sodium oxide (Na{sub 2}O), silicon dioxide (SiO{sub 2}), or titanium dioxide (TiO{sub 2}). These sealing-glass compositions are useful for forming hermetic glass-to-metal seals with titanium and titanium alloys having an improved aqueous durability and favorable sealing characteristics. Examples of the sealing-glass compositions are provided having coefficients of thermal expansionmore » about that of titanium or titanium alloys, and with sealing temperatures less than about 900 C, and generally about 700--800 C. The barium lanthanoborate sealing-glass compositions are useful for components and devices requiring prolonged exposure to moisture or water, and for implanted biomedical devices (e.g. batteries, pacemakers, defibrillators, pumps). 1 fig.« less

76 FR 52313 - Heavy Forged Hand Tools (i.e., Axes & Adzes, Bars & Wedges, Hammers & Sledges, and Picks...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-22

... DEPARTMENT OF COMMERCE International Trade Administration [A-570-803] Heavy Forged Hand Tools (i.e... Administration, Department of Commerce. SUMMARY: As a result of the determinations by the Department of Commerce... on heavy forged hand tools (i.e., [[Page 52314

Surface modification of titanium and titanium alloys by ion implantation.

PubMed

Rautray, Tapash R; Narayanan, R; Kwon, Tae-Yub; Kim, Kyo-Han

2010-05-01

Titanium and titanium alloys are widely used in biomedical devices and components, especially as hard tissue replacements as well as in cardiac and cardiovascular applications, because of their desirable properties, such as relatively low modulus, good fatigue strength, formability, machinability, corrosion resistance, and biocompatibility. However, titanium and its alloys cannot meet all of the clinical requirements. Therefore, to improve the biological, chemical, and mechanical properties, surface modification is often performed. In view of this, the current review casts new light on surface modification of titanium and titanium alloys by ion beam implantation. (c) 2010 Wiley Periodicals, Inc.

Gentamicin-Eluting Titanium Dioxide Nanotubes Grown on the Ultrafine-Grained Titanium.

PubMed

Nemati, Sima Hashemi; Hadjizadeh, Afra

2017-08-01

Titanium (Ti)-based materials is the most appropriate choices for the applications as orthopedic and dental implants. In this regard, ultrafine-grained (UFG) titanium with an enhanced mechanical properties and surface energy has attracted more attention. Titanium dioxide (TiO 2 ) nanotubes grown on the titanium could enhance bone bonding, cellular response and are good reservoirs for loading drugs and antibacterial agents. This article investigates gentamicin loading into and release from the TiO 2 nanotubes, grown on the UFG compared to coarse-grained (CG) titanium substrate surfaces. Equal Channel Angular Pressing (ECAP) was employed to produce the UFG structure titanium. TiO 2 nanotubes were grown by the anodizing technique on both UFG and CG titanium substrate surfaces. Scanning electron microscopy (SEM) imaging confirmed TiO 2 nanotube growth on the surface. The UV-vis spectroscopy analysis results show that the amount of gentamicin load-release in the anodized UFG titanium sample is higher than that of CG one which can be explained in terms of thicker TiO 2 nanotube arrays layer formed on UFG sample. Moreover, the anodized UFG titanium samples released the drug in a longer time than CG (1 day for the UFG titanium vs. 3 h for the CG one). Regarding wettability analysis, anodized UFG titanium sample showed more enhanced hydrophilicity than CG counterpart. Therefore, the significantly smaller grain size of pure titanium provided by the ECAP technique coupled with appropriate subsequent anodization treatment not only offers a good combination of biocompatibility and adequate mechanical properties but also it provides a delayed release condition for gentamicin.

The Valley Forge Encampment: Epic on the Schuylkill.

ERIC Educational Resources Information Center

Trussell, John B. B., Jr.

Valley Forge, outside Philadelphia (Pennsylvania), has long been recognized as the site of a great victory of the human spirit. Eleven thousand men including Blacks and Indians resided there during the winter of 1777-78 and triumphed over cold, starvation, nakedness, disease, and uncertainty. The encampment site was unprepared for the tattered,…

Family Health and Financial Literacy--Forging the Connection

ERIC Educational Resources Information Center

Braun, Bonnie; Kim, Jinhee; Anderson, Elaine A.

2009-01-01

Families are at-risk of or experiencing a diminished quality of living and life in current economic times and difficult decisions are required. Health and financial literacy are the basis for wise personal and public decision making. Family and consumer sciences (FCS) professionals can forge connections between health and financial literacy to…

Optimization of the Hot Forging Processing Parameters for Powder Metallurgy Fe-Cu-C Connecting Rods Based on Finite Element Simulation

NASA Astrophysics Data System (ADS)

Li, Fengxian; Yi, Jianhong; Eckert, Jürgen

2017-12-01

Powder forged connecting rods have the problem of non-uniform density distributions because of their complex geometric shape. The densification behaviors of powder metallurgy (PM) connecting rod preforms during hot forging processes play a significant role in optimizing the connecting rod quality. The deformation behaviors of a connecting rod preform, a Fe-3Cu-0.5C (wt pct) alloy compacted and sintered by the powder metallurgy route (PM Fe-Cu-C), were investigated using the finite element method, while damage and friction behaviors of the material were considered in the complicated forging process. The calculated results agree well with the experimental results. The relationship between the processing parameters of hot forging and the relative density of the connecting rod was revealed. The results showed that the relative density of the hot forged connecting rod at the central shank changed significantly compared with the relative density at the big end and at the small end. Moreover, the relative density of the connecting rod was sensitive to the processing parameters such as the forging velocity and the initial density of the preform. The optimum forging processing parameters were determined and presented by using an orthogonal design method. This work suggests that the processing parameters can be optimized to prepare a connecting rod with uniform density distribution and can help to better meet the requirements of the connecting rod industry.

Characterisation of titanium-titanium boride composites processed by powder metallurgy techniques

DOE Office of Scientific and Technical Information (OSTI.GOV)

Selva Kumar, M., E-mail: sel_mcet@yahoo.co.in; Chandrasekar, P.; Chandramohan, P.

2012-11-15

In this work, a detailed characterisation of titanium-titanium boride composites processed by three powder metallurgy techniques, namely, hot isostatic pressing, spark plasma sintering and vacuum sintering, was conducted. Two composites with different volume percents of titanium boride reinforcement were used for the investigation. One was titanium with 20% titanium boride, and the other was titanium with 40% titanium boride (by volume). Characterisation was performed using X-ray diffraction, electron probe micro analysis - energy dispersive spectroscopy and wavelength dispersive spectroscopy, image analysis and scanning electron microscopy. The characterisation results confirm the completion of the titanium boride reaction. The results reveal themore » presence of titanium boride reinforcement in different morphologies such as needle-shaped whiskers, short agglomerated whiskers and fine plates. The paper also discusses how mechanical properties such as microhardness, elastic modulus and Poisson's ratio are influenced by the processing techniques as well as the volume fraction of the titanium boride reinforcement. - Highlights: Black-Right-Pointing-Pointer Ti-TiB composites were processed by HIP, SPS and vacuum sintering. Black-Right-Pointing-Pointer The completion of Ti-TiB{sub 2} reaction was confirmed by XRD, SEM and EPMA studies. Black-Right-Pointing-Pointer Hardness and elastic properties of Ti-TiB composites were discussed. Black-Right-Pointing-Pointer Processing techniques were compared with respect to their microstructure.« less

Bone turnover and periprosthetic bone loss after cementless total hip arthroplasty can be restored by zoledronic acid: a prospective, randomized, open-label, controlled trial.

PubMed

Huang, Tsan-Wen; Wang, Chao-Jan; Shih, Hsin-Nung; Chang, Yuhan; Huang, Kuo-Chin; Peng, Kuo-Ti; Lee, Mel S

2017-05-22

Although the loss of bone mineral density (BMD) after total hip arthroplasty (THA) is a known problem, it remains unresolved. This study prospectively examined the effect of zoledronic acid (ZA) on bone turnover and BMD after cementless THA. Between January 2010 and August 2011, 60 patients who underwent cementless THA were randomly assigned to receive either ZA infusion or placebo (0.9% normal saline only) postoperatively. ZA was administered at 2 day and 1 year postoperatively. Periprosthetic BMD in seven Gruen zones was assessed preoperatively and at given time points for 2 years. Serum markers of bone turnover, functional scales, and adverse events were recorded. Each group contained 27 patients for the final analysis. The loss of BMD across all Gruen zones (significantly in zones 1 and 7) up to 2 years postoperatively was noted in the placebo group. BMD was significantly higher in the ZA group than in the placebo group in Gruen zones 1, 2, 6, and 7 at 1 year and in Gruen zones 1, 6, and 7 at 2 years (p < 0.05). Compared with baseline measures of BMD, the ZA group had increased BMD in zones 1, 2, 4, 5, 6, and 7 at 1 year and in zones 1, 4, 6, and 7 at 2 years (p < 0.05). Serum bone-specific alkaline phosphatase and N-telopeptide of procollagen I levels were significantly increased at 6 weeks in the placebo group and decreased after 3 months in the ZA group. A transient decrease in osteocalcin level was found at 6 months in the ZA group. Functional scales and adverse events were not different between the two groups. The loss of periprosthetic BMD, especially in the proximal femur (zones 1 and 7), after cementless THA could be effectively reverted using ZA. In addition, bone turnover markers were suppressed until 2 years postoperatively following ZA administration. Chang Gung Memorial Hospital Protocol Record 98-1150A3, Prevention of Periprosthetic Bone Loss After Total Hip Replacement by Annual Bisphosphonate Therapy, has been reviewed and

EVALUATION OF THE MECHANICAL PROPERTIES OF 9NI-4CO FORGINGS.

DTIC Science & Technology

FORGING, MECHANICAL PROPERTIES, STEEL , QUENCHING, SPECIFICATIONS, TENSILE PROPERTIES, COMPRESSIVE PROPERTIES, FATIGUE(MECHANICS), TOUGHNESS, STRESS...CORROSION, THERMAL STABILITY, STRAIN(MECHANICS), BAINITE , TEST METHODS, HEAT TREATMENT, CRACK PROPAGATION.

76 FR 25300 - Foreign-Trade Zone 141-Rochester, NY; Application for Manufacturing Authority, Firth Rixson, Inc...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-04

... County (see Docket 29-2011). The facility is used to produce aircraft turbine engine components of forged... aircraft turbine engines for the U.S. market and export. The manufacturing process under FTZ procedures... procedures that applies to aircraft turbine engine components and forged rings of titanium (duty rates--free...

Primary Stability Recognition of the Newly Designed Cementless Femoral Stem Using Digital Signal Processing

PubMed Central

Salleh, Sh-Hussain; Hamedi, Mahyar; Zulkifly, Ahmad Hafiz; Lee, Muhammad Hisyam; Mohd Noor, Alias; Harris, Arief Ruhullah A.; Abdul Majid, Norazman

2014-01-01

Stress shielding and micromotion are two major issues which determine the success of newly designed cementless femoral stems. The correlation of experimental validation with finite element analysis (FEA) is commonly used to evaluate the stress distribution and fixation stability of the stem within the femoral canal. This paper focused on the applications of feature extraction and pattern recognition using support vector machine (SVM) to determine the primary stability of the implant. We measured strain with triaxial rosette at the metaphyseal region and micromotion with linear variable direct transducer proximally and distally using composite femora. The root mean squares technique is used to feed the classifier which provides maximum likelihood estimation of amplitude, and radial basis function is used as the kernel parameter which mapped the datasets into separable hyperplanes. The results showed 100% pattern recognition accuracy using SVM for both strain and micromotion. This indicates that DSP could be applied in determining the femoral stem primary stability with high pattern recognition accuracy in biomechanical testing. PMID:24800230

Primary stability recognition of the newly designed cementless femoral stem using digital signal processing.

PubMed

Baharuddin, Mohd Yusof; Salleh, Sh-Hussain; Hamedi, Mahyar; Zulkifly, Ahmad Hafiz; Lee, Muhammad Hisyam; Mohd Noor, Alias; Harris, Arief Ruhullah A; Abdul Majid, Norazman

2014-01-01

Stress shielding and micromotion are two major issues which determine the success of newly designed cementless femoral stems. The correlation of experimental validation with finite element analysis (FEA) is commonly used to evaluate the stress distribution and fixation stability of the stem within the femoral canal. This paper focused on the applications of feature extraction and pattern recognition using support vector machine (SVM) to determine the primary stability of the implant. We measured strain with triaxial rosette at the metaphyseal region and micromotion with linear variable direct transducer proximally and distally using composite femora. The root mean squares technique is used to feed the classifier which provides maximum likelihood estimation of amplitude, and radial basis function is used as the kernel parameter which mapped the datasets into separable hyperplanes. The results showed 100% pattern recognition accuracy using SVM for both strain and micromotion. This indicates that DSP could be applied in determining the femoral stem primary stability with high pattern recognition accuracy in biomechanical testing.

Current forgings and their properties for steam generator of nuclear plant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tsukada, Hisashi; Suzuki, Komei; Kusuhashi, Mikio

1997-12-31

Current steel forgings for steam generator (SG) of PWR plant are reviewed in the aspect of design and material improvement. The following three items are introduced. The use of integral type steel forgings for the fabrication of steam generator enhances the structural integrity and makes easier fabrication and inspection including in-service inspection. The following examples of current integral type forgings developed by the Japan Steel Works, Ltd. (JSW) are introduced: (1) primary head integrated with nozzles, manways and supports; (2) steam drum head integrated with nozzle and handhole; (3) conical shell integrated with cylindrical sections and handholes. In order tomore » decrease the weight of steam generator, the high strength materials such as SA508, Cl.3a steel have been adopted in some cases. The properties of this steel are introduced and the chemistry and heat treatment condition are discussed. As one of the methods to minimize the macro- and micro-segregations, the use of vacuum carbon deoxidation (VCD), i.e. deoxidization of steel by gaseous CO reaction, with addition of Al for grain refining was investigated. The properties of SA508, Cl.3 steels with Low Si content are compared with those of conventional one.« less

Nine percent nickel steel heavy forging weld repair study. [National Transonic Wind Tunnel fan components

NASA Technical Reports Server (NTRS)

Young, C. P., Jr.; Gerringer, A. H.; Brooks, T. G.; Berry, R. F., Jr.

1978-01-01

The feasibility of making weld repairs on heavy section 9% nickel steel forgings such as those being manufactured for the National Transonic Facility fan disk and fan drive shaft components was evaluated. Results indicate that 9% nickel steel in heavy forgings has very good weldability characteristics for the particular weld rod and weld procedures used. A comparison of data for known similar work is included.

Titanium hermetic seals

DOEpatents

Brow, Richard K.; Watkins, Randall D.

1995-07-04

Titanium is prenitrided by being heated in a nitrogen environment under conditions which give rise to the formation of a titanium-nitride surface layer on the titanium. Titanium thus prenitrided may be used in electrical components which are hermetically sealed using silicate glasses and standard glass sealing techniques. According to the method of the invention, alkali volatilization and formation of deleterious interfacial silicide are inhibited.

Titanium hermetic seals

DOEpatents

Brow, Richard K.; Watkins, Randall D.

1995-01-01

Titanium is prenitrided by being heated in a nitrogen environment under conditions which give rise to the formation of a titanium-nitride surface layer on the titanium. Titanium thus prenitrided may be used in electrical components which are hermetically sealed using silicate glasses and standard glass sealing techniques. According to the method of the invention, alkali volatilization and formation of deleterious interfacial silicide are inhibited.

Influence of die geometry and material selection on the behavior of protective die covers in closed-die forging

NASA Astrophysics Data System (ADS)

Yu, Yingyan; Rosenstock, Dirk; Wolfgarten, Martin; Hirt, Gerhard

2016-10-01

Due to the fact that tooling costs make up to 30% of total costs of the final forged part, the tool life is always one main research topic in closed-die forging [1]. To improve the wear resistance of forging dies, many methods like nitriding and deposition of ceramic layers have been used. However, all these methods will lose its effect after a certain time, then tool repair or exchange is needed, which requires additional time and costs. A new method, which applies an inexpensive and changeable sheet metal on the forging die to protect it from abrasive wear, was firstly proposed in [2]. According to the first investigation, the die cover is effective for decreasing thermal and mechanical loads, but there are still several challenges to overcome in this concept, like wrinkling and thinning of the die cover. Therefore, an experimental study using different geometries and die cover materials is presented within this work. The results indicate the existence of feasible application cases of this concept, since conditions are found under which a die cover made of 22MnB5 still keeps its original shape even after 7 forging cycles.

What history reveals about Forge River pollution on Long Island, New York's south shore.

PubMed

Swanson, R Lawrence; Brownawell, B; Wilson, Robert E; O'Connell, Christine

2010-06-01

Fifty years ago, the Forge River and Moriches Bay, of Long Island's south shore lagoonal system, achieved notoriety when their polluted conditions were alluded to in a report of the US President's Science Advisory Committee (1965). The Woods Hole Oceanographic Institution investigated the bay throughout the 1950s, identifying duck farming as the cause of "objectionable", "highly contaminated" conditions of these waters. Much has changed: duck farming declined; the river was dredged to remove polluted sediments, improve navigation; and barrier island inlets stabilized. Yet, the river remains seasonally eutrophic. Why? This paper reviews what occurred in the Forge River watershed. While governments aggressively curtailed the impacts of duck pollution, they failed to manage development and sewage pollution. The Forge experience indicates that watershed management is a continuing governmental responsibility as development accelerates. Otherwise, we will always be looking for that instantaneous remediation that is usually not affordable and is socially contentious.

27 CFR 447.22 - Forgings, castings, and machined bodies.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 27 Alcohol, Tobacco Products and Firearms 3 2013-04-01 2013-04-01 false Forgings, castings, and machined bodies. 447.22 Section 447.22 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION IMPORTATION OF ARMS, AMMUNITION AND...

27 CFR 447.22 - Forgings, castings, and machined bodies.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 27 Alcohol, Tobacco Products and Firearms 3 2012-04-01 2010-04-01 true Forgings, castings, and machined bodies. 447.22 Section 447.22 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION IMPORTATION OF ARMS, AMMUNITION AND...

27 CFR 447.22 - Forgings, castings, and machined bodies.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 27 Alcohol, Tobacco Products and Firearms 3 2014-04-01 2014-04-01 false Forgings, castings, and machined bodies. 447.22 Section 447.22 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION IMPORTATION OF ARMS, AMMUNITION AND...

27 CFR 447.22 - Forgings, castings, and machined bodies.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 27 Alcohol, Tobacco Products and Firearms 3 2011-04-01 2010-04-01 true Forgings, castings, and machined bodies. 447.22 Section 447.22 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION IMPORTATION OF ARMS, AMMUNITION AND...

Queen City Forging Revitalized by Oak Ridge National Lab Partnership – U.S. Department of Energy

ScienceCinema

Mayer, Rob; Blue, Craig

2018-01-16

Oak Ridge National Laboratory, with support from the U.S. Department of Energy, teamed up with Queen City Forging, the U.S. Forging Industry, and Infrared Heating Technologies to develop a rapid-infrared heating furnace to produce aluminum turbochargers.

Management of an infected cementless cup with prosthetic retention and antibiotic therapy in a dog.

PubMed

Dan, B J; Kim, S E; Pozzi, A

2014-11-01

A two-year-old Rottweiler presented for acute onset of a right hindlimb lameness 20 weeks after a cementless total hip replacement (THR) and 16 weeks after open reduction to address luxation of the THR. Radiographs revealed periosteal proliferation of the medial acetabulum and a stable implant. Synovial fluid cytology was consistent with inflammatory joint fluid. Treatment consisted of surgical debridement and intravenous and oral antibiotics. THR implants were not removed. Culture of tissue removed from the THR site yielded growth of Pseudomonas and Staphylococcus species. Lameness resolved 2 months after surgery. Twenty months after surgery, the dog was exercising normally with no clinical lameness and pelvic radiographs revealed no evidence of implant loosening and markedly decreased periosteal reaction. To the authors' knowledge, this is the first report of an infected THR site successfully treated without prosthesis explantation in the dog. © 2014 British Small Animal Veterinary Association.

6. NORTH END OF MACHINE SHOP. FORGE SHOP (HAER No. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. NORTH END OF MACHINE SHOP. FORGE SHOP (HAER No. CA-326-K) ON LEFT, FORD PLANT IN DISTANCE, NE BY 60. - Rosie the Riveter National Historical Park, Machine Shop, 1311 Canal Boulevard, Richmond, Contra Costa County, CA

Computer-Aided Design of Manufacturing Chain Based on Closed Die Forging for Hardly Deformable Cu-Based Alloys

NASA Astrophysics Data System (ADS)

Pietrzyk, Maciej; Kuziak, Roman; Pidvysots'kyy, Valeriy; Nowak, Jarosław; Węglarczyk, Stanisław; Drozdowski, Krzysztof

2013-07-01

Two copper-based alloys were considered, Cu-1 pct Cr and Cu-0.7 pct Cr-1 pct Si-2 pct Ni. The thermal, electrical, and mechanical properties of these alloys are given in the paper and compared to pure copper and steel. The role of aging and precipitation kinetics in hardening of the alloys is discussed based upon the developed model. Results of plastometric tests performed at various temperatures and various strain rates are presented. The effect of the initial microstructure on the flow stress was investigated. Rheologic models for the alloys were developed. A finite element (FE) model based on the Norton-Hoff visco-plastic flow rule was applied to the simulation of forging of the alloys. Analysis of the die wear for various processes of hot and cold forging is presented as well. A microstructure evolution model was implemented into the FE code, and the microstructure and mechanical properties of final products were predicted. Various variants of the manufacturing cycles were considered. These include different preheating schedules, hot forging, cold forging, and aging. All variants were simulated using the FE method and loads, die filling, tool wear, and mechanical properties of products were predicted. Three variants giving the best combination of forging parameters were selected and industrial trials were performed. The best manufacturing technology for the copper-based alloys is proposed.

Development of SiC Nanoparticles and Second Phases Synergistically Reinforced Mg-Based Composites Processed by Multi-Pass Forging with Varying Temperatures.

PubMed

Nie, Kaibo; Guo, Yachao; Deng, Kunkun; Wang, Xiaojun; Wu, Kun

2018-01-13

In this study, SiC nanoparticles were added into matrix alloy through a combination of semisolid stirring and ultrasonic vibration while dynamic precipitation of second phases was obtained through multi-pass forging with varying temperatures. During single-pass forging of the present composite, as the deformation temperature increased, the extent of recrystallization increased, and grains were refined due to the inhibition effect of the increasing amount of dispersed SiC nanoparticles. A small amount of twins within the SiC nanoparticle dense zone could be found while the precipitated phases of Mg 17 Al 12 in long strips and deformation bands with high density dislocations were formed in the particle sparse zone after single-pass forging at 350 °C. This indicated that the particle sparse zone was mainly deformed by dislocation slip while the nanoparticle dense zone may have been deformed by twinning. The yield strength and ultimate tensile strength of the composites were gradually enhanced through increasing the single-pass forging temperature from 300 °C to 400 °C, which demonstrated that initial high forging temperature contributed to the improvement of the mechanical properties. During multi-pass forging with varying temperatures, the grain size of the composite was gradually decreased while the grain size distribution tended to be uniform with reducing the deformation temperature and extending the forging passes. In addition, the amount of precipitated second phases was significantly increased compared with that after multi-pass forging under a constant temperature. The improvement in the yield strength of the developed composite was related to grain refinement strengthening and Orowan strengthening resulting from synergistical effect of the externally applied SiC nanoparticles and internally precipitated second phases.

Fallon, Nevada FORGE Seismic Reflection Profiles

DOE Data Explorer

Blankenship, Doug; Faulds, James; Queen, John; Fortuna, Mark

2018-02-01

Newly reprocessed Naval Air Station Fallon (1994) seismic lines: pre-stack depth migrations, with interpretations to support the Fallon FORGE (Phase 2B) 3D Geologic model. Data along seven profiles (>100 km of total profile length) through and adjacent to the Fallon site were re-processed. The most up-to-date, industry-tested seismic processing techniques were utilized to improve the signal strength and coherency in the sedimentary, volcanic, and Mesozoic crystalline basement sections, in conjunction with fault diffractions in order to improve the identification and definition of faults within the study area.

31 CFR 370.40 - Can I be held accountable if my negligence contributes to a forged signature?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Can I be held accountable if my negligence contributes to a forged signature? 370.40 Section 370.40 Money and Finance: Treasury Regulations... if my negligence contributes to a forged signature? (a) General. If your failure to exercise ordinary...

Titanium disilicide formation by sputtering of titanium on heated silicon substrate

NASA Astrophysics Data System (ADS)

Tanielian, M.; Blackstone, S.

1984-09-01

We have sputter deposited titanium on bare silicon substrates at elevated temperatures. We find that at a substrate temperature of about 515 °C titanium silicide is formed due to the reaction of the titanium with the Si. The resistivity of the silicide is about 15 μΩ cm and it is not etchable in a selective titanium etch. This process can have applications in low-temperature, metal-oxide-semiconductor self-aligned silicide formation for very large scale integrated

Preparation of titanium diboride powder

DOEpatents

Brynestad, Jorulf; Bamberger, Carlos E.

1985-01-01

Finely-divided titanium diboride or zirconium diboride powders are formed by reacting gaseous boron trichloride with a material selected from the group consisting of titanium powder, zirconium powder, titanium dichloride powder, titanium trichloride powder, and gaseous titanium trichloride.

5. VIEW OF 20TON STEAMPOWERED FORGE HAMMER Manufactured by Chambersburg ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. VIEW OF 20-TON STEAM-POWERED FORGE HAMMER Manufactured by Chambersburg Engineering Company, Chambersburg, Pennsylvania - Juniata Shops, Blacksmith Shop No. 1, East of Fourth Avenue at Second Street, Altoona, Blair County, PA

Ibandronate and cementless total hip arthroplasty: densitometric measurement of periprosthetic bone mass and new therapeutic approach to the prevention of aseptic loosening

PubMed Central

Muratore, Maurizio; Quarta, Eugenio; Quarta, Laura; Calcagnile, Fabio; Grimaldi, Antonella; Orgiani, M. Antonio; Marsilio, Antonio; Rollo, Giuseppe

2012-01-01

Summary Studies of the mechanisms of periprosthetic bone loss have led to the development of pharmacologic strategies intended to enhance bone mass recovery after surgery and consequently prevent aseptic loosening and prolong the implant survival. Bisphosphonates, potent anti-resorptive drugs widely used in the treatment of osteoporosis and other disorders of bone metabolism, were shown to be particularly effective in reducing periprosthetic bone resorption in the first year after hip and knee arthroplasty, both cemented and cementless. Based on these results, we investigated the inhibitory effects of ibandronate on periprosthetic bone loss in a 2-year study of postmenopausal women that underwent cementless total hip arthroplasty. In the first 6 months both groups (A, treated with ibandronate 3 mg i.v. within five days after surgery and then with oral ibandronate 150 mg/month, plus calcium and vitamin D supplementation; and B, treated with calcium and vitamin D supplementation only) experienced bone loss, though to a lesser extent in group A. After 12 months, group A showed a remarkable BMD recovery, that was statistically significant versus baseline values (about +1, 74% of global BMD) and most evident in region R1 (+3, 81%) and R2 (+4, 12%); in group B, on the contrary, BMD values were unchanged compared with those at 6 months post-surgery. Quality of life scores also showed a greater improvement in group A, both at 6 and 12 months after surgery, likely because of the pain-reducing effects of ibandronate treatment. PMID:22783337

Electronic Portfolios in Teacher Education: Forging a Middle Ground

ERIC Educational Resources Information Center

Strudler, Neal; Wetzel, Keith

2012-01-01

At a time when implementation of electronic portfolios (EPs) is expanding, the issues of clarifying their purposes continue to plague teacher education programs. Are student-centered uses of EPs compatible with program assessment and accreditation efforts? Is this an either/or situation, or can a productive middle ground be forged? This article…

Development of SiC Nanoparticles and Second Phases Synergistically Reinforced Mg-Based Composites Processed by Multi-Pass Forging with Varying Temperatures

PubMed Central

Nie, Kaibo; Guo, Yachao; Deng, Kunkun; Wang, Xiaojun; Wu, Kun

2018-01-01

In this study, SiC nanoparticles were added into matrix alloy through a combination of semisolid stirring and ultrasonic vibration while dynamic precipitation of second phases was obtained through multi-pass forging with varying temperatures. During single-pass forging of the present composite, as the deformation temperature increased, the extent of recrystallization increased, and grains were refined due to the inhibition effect of the increasing amount of dispersed SiC nanoparticles. A small amount of twins within the SiC nanoparticle dense zone could be found while the precipitated phases of Mg17Al12 in long strips and deformation bands with high density dislocations were formed in the particle sparse zone after single-pass forging at 350 °C. This indicated that the particle sparse zone was mainly deformed by dislocation slip while the nanoparticle dense zone may have been deformed by twinning. The yield strength and ultimate tensile strength of the composites were gradually enhanced through increasing the single-pass forging temperature from 300 °C to 400 °C, which demonstrated that initial high forging temperature contributed to the improvement of the mechanical properties. During multi-pass forging with varying temperatures, the grain size of the composite was gradually decreased while the grain size distribution tended to be uniform with reducing the deformation temperature and extending the forging passes. In addition, the amount of precipitated second phases was significantly increased compared with that after multi-pass forging under a constant temperature. The improvement in the yield strength of the developed composite was related to grain refinement strengthening and Orowan strengthening resulting from synergistical effect of the externally applied SiC nanoparticles and internally precipitated second phases. PMID:29342883

Simulation of 7050 Wrought Aluminum Alloy Wheel Die Forging and its Defects Analysis based on DEFORM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang Shiquan; Yi Youping; Zhang Yuxun

2010-06-15

Defects such as folding, intercrystalline cracking and flow lines outcrop are very likely to occur in the forging of aluminum alloy. Moreover, it is difficult to achieve the optimal set of process parameters just by trial and error within an industrial environment. In producing 7050 wrought aluminum alloy wheel, a rigid-plastic finite element method (FEM) analysis has been performed to optimize die forging process. Processing parameters were analyzed, focusing on the effects of punch speed, friction factor and temperature. Meanwhile, mechanism as well as the evolution with respect to the defects of the wrought wheel was studied in details. Frommore » an analysis of the results, isothermal die forging was proposed for producing 7050 aluminum alloy wheel with good mechanical properties. Finally, verification experiment was carried out on hydropress.« less

Sealing glasses for titanium and titanium alloys

DOEpatents

Brow, Richard K.; Watkins, Randall D.

1992-01-01

Glass compositions containing CaO, Al.sub.2 O.sub.3, B.sub.2 O.sub.3, SrO and BaO of various combinations of mole % are provided. These compositions are capable of forming stable glass-to-metal seals with titanium and titanium alloys, for use in components such as seals for battery headers.

Sealing glasses for titanium and titanium alloys

DOEpatents

Brow, R.K.; Watkins, R.D.

1988-01-21

Glass compositions containing CaO, Al/sub 2/O/sub 3/, B/sub 2/O/sub 3/, SrO and BaO of various combinations of mole % are provided. These compositions are capable of forming stable glass-to-metal seals with titanium and titanium alloys, for use in components such as seals for battery headers.

Leaching of Titanium and Silicon from Low-Grade Titanium Slag Using Hydrochloric Acid Leaching

NASA Astrophysics Data System (ADS)

Zhao, Longsheng; Wang, Lina; Qi, Tao; Chen, Desheng; Zhao, Hongxin; Liu, Yahui; Wang, Weijing

2018-05-01

Acid-leaching behaviors of the titanium slag obtained by selective reduction of vanadium-bearing titanomagnetite concentrates were investigated. It was found that the optimal leaching of titanium and silicon were 0.7% and 1.5%, respectively. The titanium and silicon in the titanium slag were firstly dissolved in the acidic solution to form TiO2+ and silica sol, and then rapidly reprecipitated, forming hydrochloric acid (HCl) leach residue. Most of the silicon presented in the HCl leach residue as floccules-like silica gel, while most of the titanium was distributed in the nano-sized rod-like clusters with crystallite refinement and intracrystalline defects, and, as such, 94.3% of the silicon was leached from the HCl leach residue by alkaline desilication, and 96.5% of the titanium in the titanium-rich material with some rutile structure was then digested by the concentrated sulfuric acid. This provides an alternative route for the comprehensive utilization of titanium and silicon in titanium slag.

Army Combat Medic Resilience: The Process of Forging Loyalty.

PubMed

Abraham, Preetha A; Russell, Dale W; Huffman, Sarah; Deuster, Patricia; Gibbons, Susanne W

2018-03-01

This study presents a grounded theory analysis of in-depth interviews of United States Army Combat Medics (CMs) who had served in Iraq and/or Afghanistan. The study explores how 17 CMs nominated by their peers as resilient cope with military stressors in order to identify the factors that enable them to thrive amidst harsh conditions. Four distinct categories of characteristics unique to this group emerged: (1) social bonding, (2) readiness, (3) dual loyalty as performance, and (4) leader by example. Forging loyalty underpins these characteristics and represents the main process used by resilient CMs and comprised three behavior patterns: (1) commitment to the family, (2) commitment to the military mission, and (3) commitment to their guiding religious and spiritual beliefs. Prominent behavioral tendencies of forging loyalty likely developed during childhood and re-enforced by families, friends, and other role models. Based on the findings, new training and education efforts should focus on developing positive emotional, environmental, and social resources to enhance the health and well-being of service members and their families.

Synthesis of Titanium Oxycarbide from Titanium Slag by Methane-Containing Gas

NASA Astrophysics Data System (ADS)

Dang, Jie; Fatollahi-Fard, Farzin; Pistorius, Petrus Christiaan; Chou, Kuo-Chih

2018-02-01

In this study, reaction steps of a process for synthesis of titanium oxycarbide from titanium slag were demonstrated. This process involves the reduction of titanium slag by a methane-hydrogen-argon mixture at 1473 K (1200 °C) and the leaching of the reduced products by hydrofluoric acid near room temperature to remove the main impurity (Fe3Si). Some iron was formed by disproportionation of the main M3O5 phase before gaseous reduction started. Upon reduction, more iron formed first, followed by reduction of titanium dioxide to suboxides and eventually oxycarbide.

Removal of titanium plates coated with anodic titanium oxide ceramic: retrospective study.

PubMed

Velich, Norbert; Németh, Zsolt; Suba, Csongor; Szabó, György

2002-09-01

Transformation of the surface of metallic titanium with titanium oxides prepared in various ways is a modern procedure. For more than 15 years, the authors have been utilizing fixing elements coated with titanium oxide ceramics, prepared by anodic oxidation and thermal treatment, for purposes of jawbone osteosynthesis. The aim of the authors' work was to assess the extent to which the titanium oxide ceramic coating influences the fate of the plates used for osteosynthesis within the human organism, in regard to the possible need for their removal. During a 5-year period, 108 of 1,396 plates coated with anodic titanium oxide had to be removed for various reasons: plate exposure (47), osteomyelitis (25), palpable swelling and tenderness (21), patient request for psychological reasons (13), or fracture of the plate (2). In none of these 108 cases was metallosis observed, which otherwise is reported relatively frequently in the vicinity of traditional titanium fixing elements, nor was any tissue damage connected with the surface of the plates. The results indicate the favorable properties of the titanium oxide ceramic surface.

Fallon, Nevada FORGE Distinct Element Reservoir Modeling

DOE Data Explorer

Blankenship, Doug; Pettitt, Will; Riahi, Azadeh; Hazzard, Jim; Blanksma, Derrick

2018-03-12

Archive containing input/output data for distinct element reservoir modeling for Fallon FORGE. Models created using 3DEC, InSite, and in-house Python algorithms (ITASCA). List of archived files follows; please see 'Modeling Metadata.pdf' (included as a resource below) for additional file descriptions. Data sources include regional geochemical model, well positions and geometry, principal stress field, capability for hydraulic fractures, capability for hydro-shearing, reservoir geomechanical model-stimulation into multiple zones, modeled thermal behavior during circulation, and microseismicity.

Examination on the use of acoustic emission for monitoring metal forging process: A study using simulation technique

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mullins, W.M.; Irwin, R.D.; Malas, J.C. III

The aim of this study is to determine the feasibility of using acoustic emission as a monitoring technique for metal forging operations. From the sensor development paradigm proposed by McClean et al. the most likely approach to determining feasibility for application is through signal recognition. For this reason, signature prediction and analysis was chosen to determine the suitability for forging applications.

Bending stiffness, torsional stability, and insertion force of cementless femoral stems.

PubMed

Incavo, S J; Johnson, C C; Churchill, D L; Beynnon, B D

2001-04-01

In cementless total hip arthroplasty, increased femoral stem flexibility and decreased fracture propensity are desirable characteristics. The slotting and tapering of the stem have been introduced to achieve this. These features should not, however, be allowed to interfere with the ability of the distal stem to provide initial mechanical stability, especially under rotation. This study was done to investigate the ability of slotted and tapered stem designs to reduce stiffness and insertion force while still maintaining adequate torsional strength. The torsional strength, maximum insertion force, and insertional work of straight, slotted, and taper stems were measured by inserting each type into rigid polyurethane foam and torque testing to failure. Bending stiffness of each stem design was calculated using numerical methods. When compared to a straight stem, a unislot stem has similar torsional strength, maximum insertional force, and work of insertion. The bending stiffness is decreased by 19% to 82% depending on the bending direction. A trislot design decreased torque strength by 29%, maximal insertion force by 36%, and work by 11%. Bending stiffness was decreased by 74% and was not dependent on bending direction. A 0.5-mm taper decreased torque strength by 11% and insertional work by 14%. No difference was seen in maximum insertional force. We conclude that the design features studied (slots and taper) are effective in decreasing stem stiffness and reducing fracture propensity.

Fallon FORGE 3D Geologic Model

DOE Data Explorer

Doug Blankenship

2016-03-01

An x,y,z scattered data file for the 3D geologic model of the Fallon FORGE site. Model created in Earthvision by Dynamic Graphic Inc. The model was constructed with a grid spacing of 100 m. Geologic surfaces were extrapolated from the input data using a minimum tension gridding algorithm. The data file is tabular data in a text file, with lithology data associated with X,Y,Z grid points. All the relevant information is in the file header (the spatial reference, the projection etc.) In addition all the fields in the data file are identified in the header.

Surface fatigue and failure characteristics of hot forged powder metal AISI 4620, AISI 4640, and machined AISI 4340 steel spur gears

NASA Technical Reports Server (NTRS)

Townsend, D. P.

1986-01-01

Spur gear surface fatigue endurance tests were conducted to investigate hot forged powder metal AISI 4620 and 4640 steel for use as a gear material, to determine endurance characteristics and to compare the results with machined AISI 4340 and 9310 steel gear materials. The as-forged and unground SISI 4620 gear exhibited a 10 percent fatigue life that was approximately one-fourth of that for AISI 9310 and less than one-half that for the AISI 4340 gears. The forged and finish ground AISI 4620 gears exhibited a 10 percent life, approximately 70 percent that of AISI 9310 and slightly better than that of AISI 4340. The AISI 4640 hot forged gears had less fracture toughness and slightly less fatigue life than the AISI 4620 test gears.

[Stress analysis of femoral stems in cementless total hip arthroplasty by two-dimensional finite element method using boundary friction layer].

PubMed

Oomori, H; Imura, S; Gesso, H

1992-04-01

To develop stem design achieving primary fixation of stems and effective load transfer to the femur, we studied stress analysis of stems in cementless total hip arthroplasty by two-dimensional finite element method using boundary friction layer in stem-bone interface. The results of analyses of stem-bone interface stresses and von Mises stresses at the cortical bones indicated that ideal stem design features would be as follows: 1) Sufficient length, with the distal end extending beyond the isthmus region. 2) Maximum possible width, to contact the cortical bones in the isthmus region. 3) No collars but a lateral shoulder at the proximal portion. 4) A distal tip, to contact the cortical bones at the distal portion.

Influence of undersized cementless hip stems on primary stability and strain distribution.

PubMed

Fottner, Andreas; Woiczinski, Matthias; Kistler, Manuel; Schröder, Christian; Schmidutz, Tobias F; Jansson, Volkmar; Schmidutz, Florian

2017-10-01

Undersizing of cementless hip stems is a risk factor for aseptic loosening and early subsidence. The purpose of this study was to evaluate the effects of undersized stems and determine whether a biomechanical study can predict the clinical results. Three consecutive sizes of a clinically proven stem (CLS Spotorno) were implanted into six composite femora (size large, Sawbones ® ), respectively. According to the Canal Fill Index (CFI), two stems (size 11.25 and 12.5) were undersized (CFI < 80%) and one stem (size 13.75) had an appropriate size (CFI > 80%). The primary stability was evaluated by measurement of 3-dimensional (3D)-micromotions under physiological adapted load and surface strains were recorded before and after implantation to detect stress-shielding processes. Both undersized stems revealed significantly higher micromotions in all regions compared to the appropriate stem. The highest micromotions were registered at the distal tip of the three stem sizes. The changes in surface strain did not show a significant difference between the three stem sizes, but the highest strain reduction was observed proximally indicating a tendency for stress shielding. This study confirms the clinical assumption that undersized stem result in a significantly reduced primary stability. Furthermore, in vitro studies allow to determine the effects of undersizing and stress shielding processes.

Effect of Friction on Barreling during cold Upset Forging of Aluminium 6082 Alloy Solid cylinders

NASA Astrophysics Data System (ADS)

Priyadarshini, Amrita; Kiran, C. P.; Suresh, K.

2018-03-01

Friction is one of the significant factors in forging operations since it affects metal flow in the die, forming load, strain distribution, tool and die life, surface quality of the product etc. In upset forging, the frictional forces at the die-workpiece interface oppose the outward flow of the material due to which the specimen develops a barrel shape. As a result, the deformation becomes non-uniform or inhomogeneous which is undesirable. Barreling can be reduced by applying effective lubricant on the surface of the platens. The objective of the present work is to study experimentally the effect of various frictional conditions (dry, grease, mineral oil) on barreling during upset forging of aluminum 6082 solid cylinders of different aspect ratio (length/diameter: 0.5, 0.75, 1). The friction coefficients are determined using the ring compression test. Curvature of barrel is determined based on the assumption that the curvature of the barrel follows the geometry of circular arc.

Research on online 3D laser scanner dimensional measurement system for heavy high-temperature forgings

NASA Astrophysics Data System (ADS)

Zhu, Jingguo; Li, Menglin; Jiang, Yan; Xie, Tianpeng; Li, Feng; Jiang, Chenghao; Liu, Ruqing; Meng, Zhe

2017-10-01

Online 3-D laser-scanner is a non-contact measurement system with high speed, high precision and easy operation, which can be used to measure heavy and high-temperature forgings. But the current online laser measurement system is mainly a mobile light indicator, which can only be used in the limited environment and lacks the capability of 3-D accurate measurement. This paper mainly introduces the structure of the online high-speed real-time 3-D measurement for heavy high-temperature forgings of Academy of Opto-Electronics (AOE), Chinese Academy of Sciences. Combining TOF pulse distance measurement with hybrid scan mode, the system can scan and acquire point cloud data of an area of 20m×10m with a 75°×40° field of view at the distance of 20m. The entire scanning time is less than 5 seconds with an accuracy of 8mm, which can meet the online dimensional measurement requirements of heavy high-temperature forgings.

Research to Conduct an Exploratory Experimental and Analytical Investigation of Alloys

DTIC Science & Technology

1980-11-01

Properties of Forged and Heat 31 Treated Alpha-Two Titanium Aluminide Alloys 10 Effect of Interstitial Elements on Room 33 Temperature Notched (Kt-3.9...percent (three to five percent of engine weight) would be achieved with widespread application of the titanium aluminides in rotating hardwarei...vanadium substitution effect was also undertaken. One of the inconsistencies in the previous titanium aluminide investigations has been the poorer

Roosevelt Hot Springs, Utah FORGE Ground Motion Study Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moore, Joe

Paragon Geophysical contracted Urban Seismic Specialists to conduct A Ground Motion Study, on their Forge 3D project located near in Milford Utah .The test was conducted to measure the effects of the vibrator array on a pipeline owned by Kern River. Testing began November 22nd, and was completed on November 23rd. Demobilizing was completed on November 24, 2017

Recovery of titanium values from titanium grinding swarf by electric furnace smelting

DOEpatents

Gerdemann, Stephen J.; White, Jack C.

1999-01-01

A method for the recovery of valuable materials from titanium grinding swarf is provided comprising the steps of sieving the accumulated titanium grinding swarf to remove unwanted coarse trash and grinding wheel fragments, pelletizing, and smelting in an electric arc furnace to produce ferrotitanium and/or high titanium slag.

Recovery of titanium values from titanium grinding swarf by electric furnace smelting

DOEpatents

Gerdemann, Stephen J.; White, Jack C.

1998-01-01

A method for the recovery of valuable materials from titanium grinding swarf is provided comprising the steps of sieving the accumulated titanium grinding swarf to remove unwanted coarse trash and grinding wheel fragments, pelletizing, and smelting in an electric arc furnace to produce ferrotitanium and/or high titanium slag.

Formation of Titanium Sulfide from Titanium Oxycarbonitride by CS2 Gas

NASA Astrophysics Data System (ADS)

Ahmadi, Eltefat; Yashima, Yuta; Suzuki, Ryosuke O.; Rezan, Sheikh Abdul

2018-05-01

Previously this group reported that a good quality titanium metal powder can be produced from titanium sulfides by electrochemical OS process. In this study, the sulfurization procedure was examined to synthesize titanium sulfide from titanium oxycarbonitride by CS2 gas. The experiments were carried out in the temperature range of 1173 K to 1523 K (900 °C to 1250 °C) in a tube reactor with continuously flowing argon (Ar) as carrier gas of CS2. The formation of titanium sulfide phases from the commercial TiN, TiC, and TiO powders was studied as the initial step. Then, TiO0.02C0.13N0.85 coming from ilmenite was sulfurized to prepare single phase of titanium sulfide. The products were characterized by X-ray diffraction, and the morphology of the sulfides was rigorously investigated, and the sulfur, oxygen, and carbon contents in the products were analyzed. The process was remarkably dependent on the temperature and time. TiN and TiO0.02C0.13N0.85 powders could be fully converted to the single phase of Ti2.45S4 (Ti2+x S4) at 1473 K (1200 °C) in 3.6 ks. The maximum weight gain of TiN sample was 55.3 pct indicating a full conversion of TiN to Ti2S3 phase. The carbon and oxygen contents in this sulfide prepared from the oxycarbonitride were about 1.8 wt pct C and 1.4 wt pct O, respectively. Therefore, the titanium sulfide could be a promising feedstock for the production of commercial grade titanium powder.

The effect of forging history on the strength and microstructure of TDNiCr /Ni-20Cr-2ThO2/

NASA Technical Reports Server (NTRS)

Filippi, A. M.

1975-01-01

Forging variables were evaluated to determine their influence on the elevated temperature strength and microstructure of TDNiCr. Grain size was the principal microstructural feature related to elevated temperature strength and was controlled primarily by the thermomechanical variables of forging temperature and final annealing condition. Tests at 1366 K revealed a factor of eight increase in tensile strength as grain size increased from 1 to 150 microns, while stress-rupture strength improved by three to five times as grain size increased from 15 to 150 microns. Forged material of grain size greater than or equal to about 150 microns displayed a level of elevated temperature strength comparable to that of optimized TDNiCr sheet. The presence of a preponderance of small twins and a strong preferred orientation may have also been factors contributing to the excellent high temperature strength of large grain forged material.

Recovery of titanium values from titanium grinding swarf by electric furnace smelting

DOEpatents

Gerdemann, S.J.; White, J.C.

1998-08-04

A method for the recovery of valuable materials from titanium grinding swarf is provided comprising the steps of sieving the accumulated titanium grinding swarf to remove unwanted coarse trash and grinding wheel fragments, pelletizing, and smelting in an electric arc furnace to produce ferrotitanium and/or high titanium slag. 1 fig.

Simulation of forming a flat forging

NASA Astrophysics Data System (ADS)

Solomonov, K.; Tishchuk, L.; Fedorinin, N.

2017-11-01

The metal flow in some of the metal shaping processes (rolling, pressing, die forging) is subjected to the regularities which determine the scheme of deformation in the metal samples upsetting. The object of the study was the research of the metal flow picture including the contour of the part, the demarcation lines of the metal flow and the flow lines. We have created an algorithm for constructing the metal flow picture, which is based on the representation of the metal flow demarcation line as an equidistant. Computer and physical simulation of the metal flow picture with the help of various software systems confirms the suggested hypothesis.

A Comparison between the Properties of Solid Cylinders and Tube Products in Multi-Pass Hot Radial Forging Using Finite Element Method

NASA Astrophysics Data System (ADS)

Abedian, A.; Poursina, M.; Golestanian, H.

2007-05-01

Radial forging is an open die forging process used for reducing the diameter of shafts, tubes, stepped shafts and axels, and creating internal profiles for tubes such as rifling of gun barrels. In this work, a comprehensive study of multi-pass hot radial forging of short hollow and solid products are presented using 2-D axisymmetric finite element simulation. The workpiece is modeled as an elastic-viscoplastic material. A mixture of Coulomb law and constant limit shear is used to model the die-workpiece and mandrel-workpiece contacts. Thermal effects are also taken in to account. Three-pass radial forging of solid cylinders and tube products are considered. Temperature, stress, strain and metal flow distribution are obtained in each pass through thermo-mechanical simulation. The numerical results are compared with available experimental data and are in good agreement with them.

Scale-Up of a Titanium Carbonitride Coating System for Titanium Alloys.

DTIC Science & Technology

1980-07-01

Ti-Cote C on JT12 Compressor 7th-Stage Airfoil -Optical Photomicrograph Porosity in Ti-Cote C Titanium 6AI- 4V Substrate - -- Mag: 1000OX FD 171506...30 21 TiCN Coating on Titanium 6A1- 4V ...indication of any corrosive damage to the titanium 6A1- 4V . This had been a matter of concern due to the corrosive nature of the reactive gases and

Wear Improvement of Tools in the Cold Forging Process for Long Hex Flange Nuts.

PubMed

Hsia, Shao-Yi; Shih, Po-Yueh

2015-09-25

Cold forging has played a critical role in fasteners and has been widely used in automotive production, manufacturing, aviation and 3C (Computer, Communication, and Consumer electronics). Despite its extensive use in fastener forming and die design, operator experience and trial and error make it subjective and unreliable owing to the difficulty of controlling the development schedule. This study used finite element analysis to establish and simulate wear in automotive repair fastener manufacturing dies based on actual process conditions. The places on a die that wore most quickly were forecast, with the stress levels obtained being substituted into the Archard equation to calculate die wear. A 19.87% improvement in wear optimization occurred by applying the Taguchi quality method to the new design. Additionally, a comparison of actual manufacturing data to simulations revealed a nut forging size error within 2%, thereby demonstrating the accuracy of this theoretical analysis. Finally, SEM micrographs of the worn surfaces on the upper punch indicate that the primary wear mechanism on the cold forging die for long hex flange nuts was adhesive wear. The results can simplify the development schedule, reduce the number of trials and further enhance production quality and die life.

Roosevelt Hot Springs, Utah FORGE X-Ray Diffraction Data

DOE Data Explorer

Nash, Greg; Jones, Clay

2018-02-07

This dataset contains X-ray diffraction (XRD) data taken from wells and outcrops as part of the DOE GTO supported Utah FORGE project located near Roosevelt Hot Springs. It contains an Excel spreadsheet with the XRD data, a text file with sample site names, types, and locations in UTM, Zone 12, NAD83 coordinates, and a GIS shapefile of the sample locations with attributes.

Forging Consensus for Implementing Youth Socialization Policy in Northwest China

ERIC Educational Resources Information Center

Fairbrother, Gregory P.

2011-01-01

The goal of this article is to examine how the provincial education media in China play a role of forging consensus among local actors responsible for the implementation of new centrally-promulgated youth socialization policy. In doing so, it also explores the tension among three of the Chinese state's claims to legitimacy: economic development,…

Large forging manufacturing process

DOEpatents

Thamboo, Samuel V.; Yang, Ling

2002-01-01

A process for forging large components of Alloy 718 material so that the components do not exhibit abnormal grain growth includes the steps of: a) providing a billet with an average grain size between ASTM 0 and ASTM 3; b) heating the billet to a temperature of between 1750.degree. F. and 1800.degree. F.; c) upsetting the billet to obtain a component part with a minimum strain of 0.125 in at least selected areas of the part; d) reheating the component part to a temperature between 1750.degree. F. and 1800.degree. F.; e) upsetting the component part to a final configuration such that said selected areas receive no strains between 0.01 and 0.125; f) solution treating the component part at a temperature of between 1725.degree. F. and 1750.degree. F.; and g) aging the component part over predetermined times at different temperatures. A modified process achieves abnormal grain growth in selected areas of a component where desirable.

A coupled thermo-mechanical pseudo inverse approach for preform design in forging

NASA Astrophysics Data System (ADS)

Thomas, Anoop Ebey; Abbes, Boussad; Li, Yu Ming; Abbes, Fazilay; Guo, Ying-Qiao; Duval, Jean-Louis

2017-10-01

Hot forging is a process used to form difficult to form materials as well as to achieve complex geometries. This is possible due to the reduction of yield stress at high temperatures and a subsequent increase in formability. Numerical methods have been used to predict the material yield and the stress/strain states of the final product. Pseudo Inverse Approach (PIA) developed in the context of cold forming provides a quick estimate of the stress and strain fields in the final product for a given initial shape. In this paper, PIA is extended to include the thermal effects on the forging process. A Johnson-Cook thermo-viscoplastic material law is considered and a staggered scheme is employed for the coupling between the mechanical and thermal problems. The results are compared with available commercial codes to show the efficiency and the limitations of PIA.

Microstructural stability and thermomechanical processing of boron modified beta titanium alloys

NASA Astrophysics Data System (ADS)

Cherukuri, Balakrishna

One of the main objectives during primary processing of titanium alloys is to reduce the prior beta grain size. Producing an ingot with smaller prior beta grain size could potentially eliminate some primary processing steps and thus reduce processing cost. Trace additions of boron have been shown to decrease the as-cast grain size in alpha + beta titanium alloys. The primary focus of this dissertation is to investigate the effect of boron on microstructural stability and thermomechanical processing in beta titanium alloys. Two metastable beta titanium alloys: Ti-15Mo-2.6Nb-3Al-0.2Si (Beta21S) and Ti-5Al-5V-5Mo-3Cr (Ti5553) with 0.1 wt% B and without boron additions were used in this investigation. Significant grain refinement of the as-cast microstructure and precipitation of TiB whiskers along the grain boundaries was observed with boron additions. Beta21S and Beta21S-0.1B alloys were annealed above the beta transus temperature for different times to investigate the effect of boron on grain size stability. The TiB precipitates were very effective in restricting the beta grain boundary mobility by Zener pinning. A model has been developed to predict the maximum grain size as a function of TiB size, orientation, and volume fraction. Good agreement was obtained between model predictions and experimental results. Beta21S alloys were solution treated and aged for different times at several temperatures below the beta transus to study the kinetics of alpha precipitation. Though the TiB phase did not provide any additional nucleation sites for alpha precipitation, the grain refinement obtained by boron additions resulted in accelerated aging. An investigation of the thermomechanical processing behavior showed different deformation mechanisms above the beta transus temperature. The non-boron containing alloys showed a non-uniform and fine recrystallized necklace structure at grain boundaries whereas uniform intragranular recrystallization was observed in boron containing

Bone remodelling around HA-coated acetabular cups

PubMed Central

Nielsen, P. T.; Søballe, K.

2006-01-01

This study was designed to investigate bone remodelling around the cup in cementless THA. Previous studies indicate an advantage of better sealing of the bone-prosthesis interface by HA/TCP coating of implants, inhibiting polyethylene-induced osteolysis. One hundred patients gave informed consent to participate in a controlled randomized study between porous coated Trilogy versus Trilogy Calcicoat (HA/TCP coated). The cup was inserted in press-fit fixation. The femoral component was a cementless porous coated titanium alloy stem (Bi-Metric), with a modular 28-mm CrCo head. The Harris Hip Score (HHS) and bone mineral density (BMD) determined by DEXA scanning were used to study the effect. Measurements revealed no difference between the two groups after 3 years either in the clinical outcome or in terms of periprosthetic bone density. Patients with a body mass index above normal regained more bone mineral than patients with normal weight. This finding supports the assumption that load is beneficial to bone remodelling. PMID:16761153

Energy efficient engine. Volume 2. Appendix A: Component development and integration program

NASA Technical Reports Server (NTRS)

Moracz, D. J.; Cook, C. R.

1981-01-01

The large size and the requirement for precise lightening cavities in a considerable portion of the titanium fan blades necessitated the development of a new manufacturing method. The approach which was selected for development incorporated several technologies including HIP diffusion bonding of titanium sheet laminates containing removable cores and isothermal forging of the blade form. The technology bases established in HIP/DB for composite blades and in isothermal forging for fan blades were applicable for development of the manufacturing process. The process techniques and parameters for producing and inspecting the cored diffusion bonded titanium laminate blade preform were established. The method was demonstrated with the production of twelve hollow simulated blade shapes for evaluation. Evaluations of the critical experiments conducted to establish procedures to produce hollow structures by a laminate/core/diffusion bonding approach are included. In addition the transfer of this technology to produce a hollow fan blade is discussed.

Artefacts in multimodal imaging of titanium, zirconium and binary titanium-zirconium alloy dental implants: an in vitro study.

PubMed

Smeets, Ralf; Schöllchen, Maximilian; Gauer, Tobias; Aarabi, Ghazal; Assaf, Alexandre T; Rendenbach, Carsten; Beck-Broichsitter, Benedicta; Semmusch, Jan; Sedlacik, Jan; Heiland, Max; Fiehler, Jens; Siemonsen, Susanne

2017-02-01

To analyze and evaluate imaging artefacts induced by zirconium, titanium and titanium-zirconium alloy dental implants. Zirconium, titanium and titanium-zirconium alloy implants were embedded in gelatin and MRI, CT and CBCT were performed. Standard protocols were used for each modality. For MRI, line-distance profiles were plotted to quantify the accuracy of size determination. For CT and CBCT, six shells surrounding the implant were defined every 0.5 cm from the implant surface and histogram parameters were determined for each shell. While titanium and titanium-zirconium alloy induced extensive signal voids in MRI owing to strong susceptibility, zirconium implants were clearly definable with only minor distortion artefacts. For titanium and titanium-zirconium alloy, the MR signal was attenuated up to 14.1 mm from the implant. In CT, titanium and titanium-zirconium alloy resulted in less streak artefacts in comparison with zirconium. In CBCT, titanium-zirconium alloy induced more severe artefacts than zirconium and titanium. MRI allows for an excellent image contrast and limited artefacts in patients with zirconium implants. CT and CBCT examinations are less affected by artefacts from titanium and titanium-zirconium alloy implants compared with MRI. The knowledge about differences of artefacts through different implant materials and image modalities might help support clinical decisions for the choice of implant material or imaging device in the clinical setting.

Hot Deformation Behavior and Pulse Current Auxiliary Isothermal Forging of Hot Pressing Sintering TiAl Based Alloys

PubMed Central

Shi, Chengcheng; Jiang, Shaosong; Zhang, Kaifeng

2017-01-01

This paper focuses on the fabrication of as-forged Ti46.5Al2Cr1.8Nb-(W, B) alloy via pulse current auxiliary isothermal forging (PCIF). The starting material composed of near gamma (NG) microstructure was fabricated by adopting pre-alloyed powders via hot pressing sintering (HPS) at 1300 °C. Isothermal compression tests were conducted at a strain rate range of 0.001–0.1 s−1 and a temperature range of 1125–1275 °C to establish the constitutive model and processing map. The optimal hot deformation parameters were successfully determined (in a strain rate range of 10−3–2.5 × 10−3 s−1 and temperature range of 1130–1180 °C) based on the hot processing map and microstructure observation. Accordingly, an as-forged TiAl based alloy without cracks was successfully fabricated by PCIF processing at 1175 °C with a nominal strain rate of 10−3 s−1. Microstructure observation indicated that complete dynamic recrystallization (DRX) and phase transformation of γ→α2 occurred during the PCIF process. The elongation of as-forged alloy was 136%, possessing a good secondary hot workability, while the sintered alloy was only 66% when tested at 900 °C with a strain rate of 2 × 10−4 s−1. PMID:29258198

Hot Deformation Behavior and Pulse Current Auxiliary Isothermal Forging of Hot Pressing Sintering TiAl Based Alloys.

PubMed

Shi, Chengcheng; Jiang, Shaosong; Zhang, Kaifeng

2017-12-16

This paper focuses on the fabrication of as-forged Ti46.5Al2Cr1.8Nb-(W, B) alloy via pulse current auxiliary isothermal forging (PCIF). The starting material composed of near gamma (NG) microstructure was fabricated by adopting pre-alloyed powders via hot pressing sintering (HPS) at 1300 °C. Isothermal compression tests were conducted at a strain rate range of 0.001-0.1 s -1 and a temperature range of 1125-1275 °C to establish the constitutive model and processing map. The optimal hot deformation parameters were successfully determined (in a strain rate range of 10 -3 -2.5 × 10 -3 s -1 and temperature range of 1130-1180 °C) based on the hot processing map and microstructure observation. Accordingly, an as-forged TiAl based alloy without cracks was successfully fabricated by PCIF processing at 1175 °C with a nominal strain rate of 10 -3 s -1 . Microstructure observation indicated that complete dynamic recrystallization (DRX) and phase transformation of γ→α₂ occurred during the PCIF process. The elongation of as-forged alloy was 136%, possessing a good secondary hot workability, while the sintered alloy was only 66% when tested at 900 °C with a strain rate of 2 × 10 -4 s -1 .

Bony integration of titanium implants with a novel bioactive calcium titanate (Ca4Ti3O10) surface treatment in a rabbit model.

PubMed

Haenle, Maximilian; Lindner, Tobias; Ellenrieder, Martin; Willfahrt, Manfred; Schell, Hanna; Mittelmeier, Wolfram; Bader, Rainer

2012-10-01

Nowadays total joint replacement is an indispensable component of modern medicine. The surfaces characteristics of cementless prostheses may be altered to achieve an accelerated and enduring bony integration. Classic surface coatings bear the risk of loosening or flaking from the implant body. This risk is excluded by the chemical conversion of the naturally existing TiO(2) surface layer into calcium titanate. The aim of this experimental animal study was to investigate the bony integration of implants with a new calcium titanate surface (Ca(4)Ti(3)O(10)) compared with a conventional standard Ti6Al4V surface. Cylindrical implants, made of titanium alloy (Ti6Al4V) were implanted in both lateral femoral condyles of New Zealand white rabbits. In each animal, an implant with and without surface treatment was inserted in a blinded manner. Animals were sacrificed after 4, 12, and 36 weeks, respectively. The axial pull-off forces were determined for 25 animals using a universal testing machine (Zwick Z010, Ulm, Germany). Furthermore, a histological analysis of the bony integration of the implants was performed in 12 specimens. In general, the pull-off forces for untreated and treated implants increased with longer survival times of the rabbits. No significant difference could be shown after 4 weeks between treated and untreated implants. After 12 weeks, the treated implants revealed a statistical significant higher pull-off force. After 36 weeks, the pull-off forces for treated and untreated implants aligned again. Titanium implants treated with calcium titanate, may offer an interesting and promising implant surface modification for endoprosthetic implants. They might lead to an accelerated osseointegration of total hip and knee replacements. Copyright © 2012 Wiley Periodicals, Inc.

[The surface roughness analysis of the titanium casting founding by a new titanium casting investment material].

PubMed

Liang, Qin-ye; Wu, Xia-yi; Lin, Xue-feng

2012-04-01

To investigate the surface roughness property of the titanium castings cast in a new investment for titanium casting. Six wax patterns (20 mm × 20 mm × 0.5 mm) were invested using two investments: three in a new titanium investment material and three in the control material (Rematitan Plus). Six titanium specimens were obtained by conventional casting. After casting, surface roughness of the specimens were evaluated with a surface profilometer. The surface roughness of the specimens cast in new titanium investment material was (1.72 ± 0.08) µm, which was much smaller than that from Rematitan Plus [(1.91 ± 0.15) µm, P < 0.05]. The surfaces of titanium cast using these two investment materials are both smooth enough to fulfill the demand of the titanium precision-casting for prosthodontic clinical use.

Evolution of the Ultrasonic Inspection of Heavy Rotor Forgings Over the Last Decades

NASA Astrophysics Data System (ADS)

Zimmer, A.; Vrana, J.; Meiser, J.; Maximini, W.; Blaes, N.

2010-02-01

All types of heavy forgings that are used in energy machine industry, rotor shafts as well as discs, retaining rings or tie bolts are subject to extensive nondestructive inspections before they are delivered to the customer. Due to the availability of the parts in simple shapes, these forgings are very well suited for full volmetric inspections using ultrasound. In the beginning, these inspections were carried out manually, using straight beam probes and analogue equipment. Higher requirements in reliability, efficiency, safety and power output in the machines have lead to higher requirements for the ultrasonic inspection in the form of more scanning directions, higher sensitivity demands and improved documentation means. This and the increasing use of high alloy materials for ever growing parts, increase the need for more and more sophisticated methods for testing the forgings. Angle scans and sizing technologies like DGS have been implemented, and for more than 15 years now, mechanized and automated inspections have gained importance since they allow better documentation as well as easier evaluation of the recorded data using different views (B- C- or D-Scans), projections or tomography views. The latest major development has been the availability of phased array probes to increase the flexibility of the inspection systems. Many results of the ongoing research in ultrasonic's have not been implemented yet. Today's availability of fast computers, large and fast data storages allows saving RF inspection data and applying sophisticated signal processing methods. For example linear diffraction tomography methods like SAFT offer tools for 3D reconstruction of inspection data, simplifying sizing and locating of defects as well as for improving signal to noise ratios. While such methods are already applied in medical ultrasonic's, they are still to be implemented in the steel industry. This paper describes the development of the ultrasonic inspection of heavy forgings

X-ray tomography studies on porosity and particle size distribution in cast in-situ Al-Cu-TiB{sub 2} semi-solid forged composites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mathew, James; Mandal, Animesh

X-ray computed tomography (XCT) was used to characterise the internal microstructure and clustering behaviour of TiB{sub 2} particles in in-situ processed Al-Cu metal matrix composites prepared by casting method. Forging was used in semi-solid state to reduce the porosity and to uniformly disperse TiB{sub 2} particles in the composite. Quantification of porosity and clustering of TiB{sub 2} particles was evaluated for different forging reductions (30% and 50% reductions) and compared with an as-cast sample using XCT. Results show that the porosity content was decreased by about 40% due to semi-solid forging as compared to the as-cast condition. Further, XCT resultsmore » show that the 30% forging reduction resulted in greater uniformity in distribution of TiB{sub 2} particles within the composite compared to as-cast and the 50% forge reduction in semi-solid state. These results show that the application of forging in semi-solid state enhances particle distribution and reduces porosity formation in cast in-situ Al-Cu-TiB{sub 2} metal matrix composites. - Highlights: •XCT was used to visualise 3D internal structure of Al-Cu-TiB{sub 2} MMCs. •Al-Cu-TiB{sub 2} MMC was prepared by casting using flux assisted synthesis method. •TiB{sub 2} particles and porosity size distribution were evaluated. •Results show that forging in semi-solid condition decreases the porosity content and improve the particle dispersion in MMCs.« less

Wear Improvement of Tools in the Cold Forging Process for Long Hex Flange Nuts

PubMed Central

Hsia, Shao-Yi; Shih, Po-Yueh

2015-01-01

Cold forging has played a critical role in fasteners and has been widely used in automotive production, manufacturing, aviation and 3C (Computer, Communication, and Consumer electronics). Despite its extensive use in fastener forming and die design, operator experience and trial and error make it subjective and unreliable owing to the difficulty of controlling the development schedule. This study used finite element analysis to establish and simulate wear in automotive repair fastener manufacturing dies based on actual process conditions. The places on a die that wore most quickly were forecast, with the stress levels obtained being substituted into the Archard equation to calculate die wear. A 19.87% improvement in wear optimization occurred by applying the Taguchi quality method to the new design. Additionally, a comparison of actual manufacturing data to simulations revealed a nut forging size error within 2%, thereby demonstrating the accuracy of this theoretical analysis. Finally, SEM micrographs of the worn surfaces on the upper punch indicate that the primary wear mechanism on the cold forging die for long hex flange nuts was adhesive wear. The results can simplify the development schedule, reduce the number of trials and further enhance production quality and die life. PMID:28793589

FE-simulation of hot forging with an integrated heat treatment with the objective of residual stress prediction

NASA Astrophysics Data System (ADS)

Behrens, Bernd-Arno; Chugreeva, Anna; Chugreev, Alexander

2018-05-01

Hot forming as a coupled thermo-mechanical process comprises numerous material phenomena with a corresponding impact on the material behavior during and after the forming process as well as on the final component performance. In this context, a realistic FE-simulation requires reliable mathematical models as well as detailed thermo-mechanical material data. This paper presents experimental and numerical results focused on the FE-based simulation of a hot forging process with a subsequent heat treatment step aiming at the prediction of the final mechanical properties and residual stress state in the forged component made of low alloy CrMo-steel DIN 42CrMo4. For this purpose, hot forging experiments of connecting rod geometry with a corresponding metallographic analysis and x-ray residual stress measurements have been carried out. For the coupled thermo-mechanical-metallurgical FE-simulations, a special user-defined material model based on the additive strain decomposition method and implemented in Simufact Forming via MSC.Marc solver features has been used.

Effect of solution treatment on the fatigue behavior of an as-forged Mg-Zn-Y-Zr alloy

NASA Astrophysics Data System (ADS)

Wang, S. D.; Xu, D. K.; Wang, B. J.; Han, E. H.; Dong, C.

2016-04-01

Through investigating and comparing the fatigue behavior of an as-forged Mg-6.7Zn-1.3Y-0.6Zr (wt.%) alloy before and after solid solution treatment (T4) in laboratory air, the effect of T4 treatment on fatigue crack initiation was disclosed. S-N curves illustrated that the fatigue strength of as-forged samples was 110 MPa, whereas the fatigue strength of T4 samples was only 80 MPa. Observations to fracture surfaces demonstrated that for as-forged samples, fatigue crack initiation sites were covered with a layer of oxide film. However, due to the coarse grain structure and the dissolution of MgZn2 precipitates, the activation and accumulation of {10-12} twins in T4 samples were much easier, resulting in the preferential fatigue crack initiation at cracked twin boundaries (TBs). Surface characterization demonstrated that TB cracking was mainly ascribed to the incompatible plastic deformation in the twinned area and nearby α-Mg matrix.

High Temperature, Slow Strain Rate Forging of Advanced Disk Alloy ME3

NASA Technical Reports Server (NTRS)

Gabb, Timothy P.; OConnor, Kenneth

2001-01-01

The advanced disk alloy ME3 was designed in the HSR/EPM disk program to have extended durability at 1150 to 1250 F in large disks. This was achieved by designing a disk alloy and process producing balanced monotonic, cyclic, and time-dependent mechanical properties. combined with robust processing and manufacturing characteristics. The resulting baseline alloy, processing, and supersolvus heat treatment produces a uniform, relatively fine mean grain size of about ASTM 7, with as-large-as (ALA) grain size of about ASTM 3. There is a long term need for disks with higher rim temperature capabilities than 1250 F. This would allow higher compressor exit (T3) temperatures and allow the full utilization of advanced combustor and airfoil concepts under development. Several approaches are being studied that modify the processing and chemistry of ME3, to possibly improve high temperature properties. Promising approaches would be applied to subscale material, for screening the resulting mechanical properties at these high temperatures. n obvious path traditionally employed to improve the high temperature and time-dependent capabilities of disk alloys is to coarsen the grain size. A coarser grain size than ASTM 7 could potentially be achieved by varying the forging conditions and supersolvus heat treatment. The objective of this study was to perform forging and heat treatment experiments ("thermomechanical processing experiments") on small compression test specimens of the baseline ME3 composition, to identify a viable forging process allowing significantly coarser grain size targeted at ASTM 3-5, than that of the baseline, ASTM 7.

Social Work and Engineering Collaboration: Forging Innovative Global Community Development Education

ERIC Educational Resources Information Center

Gilbert, Dorie J.

2014-01-01

Interdisciplinary programs in schools of social work are growing in scope and number. This article reports on collaboration between a school of social work and a school of engineering, which is forging a new area of interdisciplinary education. The program engages social work students working alongside engineering students in a team approach to…

Oxidation resistant coating for titanium alloys and titanium alloy matrix composites

NASA Technical Reports Server (NTRS)

Brindley, William J. (Inventor); Smialek, James L. (Inventor); Rouge, Carl J. (Inventor)

1992-01-01

An oxidation resistant coating for titanium alloys and titanium alloy matrix composites comprises an MCrAlX material. M is a metal selected from nickel, cobalt, and iron. X is an active element selected from Y, Yb, Zr, and Hf.

Method for Surface Texturing Titanium Products

NASA Technical Reports Server (NTRS)

Banks, Bruce A. (Inventor)

1998-01-01

The present invention teaches a method of producing a textured surface upon an arbitrarily configured titanium or titanium alloy object for the purpose of improving bonding between the object and other materials such as polymer matrix composites and/or human bone for the direct in-growth of orthopaedic implants. The titanium or titanium alloy object is placed in an electrolytic cell having an ultrasonically agitated solution of sodium chloride therein whereby a pattern of uniform "pock mark" like pores or cavities are produced upon the object's surface. The process is very cost effective compared to other methods of producing rough surfaces on titanium and titanium alloy components. The surface textures produced by the present invention are etched directly into the parent metal at discrete sites separated by areas unaffected by the etching process. Bonding materials to such surface textures on titanium or titanium alloy can thus support a shear load even if adhesion of the bonding material is poor.

[Silicate coating of cemented titanium-based shafts in hip prosthetics reduces high aseptic loosening].

PubMed

Marx, R; Faramarzi, R; Jungwirth, F; Kleffner, B V; Mumme, T; Weber, M; Wirtz, D C

2009-01-01

For cemented hip prostheses, all requirements can be fulfilled by using forged Co/Cr/Mo stems. Co/Cr/Mo alloys, however, are contraindicated for allergy sufferers. For these patients, a cemented prosthesis made of titanium (alloy) would be indicated. Cemented stems from titanium (alloy), depending on the geometry of the prosthesis and its specific surface texture, however, may have loosening rates which are clinically not tolerable. In comparison to Co/Cr/Mo alloys, the greater roughness in conjunction with lesser abrasion resistance of titanium-based alloys leads to high loosening rates caused by abrasion. On the other hand, the greater surface roughness permits good mechanical retention of bone cement to the surface. Good mechanical retention enhances migration behaviour and reduces micromotions. However, there is no stable hydrolytic bond between bone cement and metallic surface; intermediate-term debonding between metal and bone cement is predictable. This debonding results in relative movements, consequently in wear particles which have their origin both from the rough metallic surface and from the PMMA cement. The roughness of the metallic surface operates as emery and with that, a rubbing wear from the PMMA. For the above reasons, a low or moderate roughness is essential for easily abradable implants such as shafts made of titanium (alloy) because low roughness provides a fail-safe running function in case of debonding. Thus, one must allow for inappropriate migration behaviour accompanied by greater micromotions due to insufficient mechanical retention in the case of low roughness. This can be accomplished by a silicate layer coating applied to the metal shaft surface via electrochemical "ECD" or physical vapour deposition "PVD". For analysis, specimens (screws for pull-out, cones for push-out tests) were sand-blasted, so that roughnesses between Ra = 0.8 microm (Rz = 4 microm) and Ra = 2.0 microm (Rz = 9 microm) were generated. The bond strengths observed

Effects of silicon coating on bond strength of two different titanium ceramic to titanium.

PubMed

Ozcan, Isil; Uysal, Hakan

2005-08-01

This study investigated the effect of silicon coating (SiO2) by magnetron sputtering on bond strength of two different titanium ceramics to titanium. Sixty cast titanium specimens were prepared following the protocol ISO 9693. Titanium specimens were divided into two test and control groups with 15 specimens in each. Test groups were silicon coated by the magnetron sputtering technique. Two titanium ceramics (Triceram and Duceratin) were applied on both test (coated) and control (uncoated) metal specimens. The titanium-ceramic specimens were subjected to a three point flexural test. The groups were compared for their bond strength. SEM and SEM/EDS analyses were performed on the delaminated titanium surfaces to ascertain bond failure. The mean bond strength of Ti-Duceratin, Ti-Triceram, Si-coated Ti-Duceratin and Si-coated Ti-Triceram were 17.22+/-2.43, 23.31+/-3.18, 23.21+/-3.81 and 24.91+/-3.70 MPa, respectively. While the improvement in bond strength was 30% for Duceratin, it was statistically insignificant for Triceram. An adhesive mode of failure was observed in the Duceratin control group. In the silicoated Duceratin specimen, the bonded ceramic boundaries were wider but less than in the silicoated Triceram specimen. In the coated Triceram specimen, the ceramic retained areas were frequent and the failure mode was generally cohesive. Silicon coating was significantly effective in both preventing titanium oxide layer formation and in improving bond strength for Duceratin. However, it was of less value for Triceram.

Acceleration of Intended Pozzolanic Reaction under Initial Thermal Treatment for Developing Cementless Fly Ash Based Mortar.

PubMed

Kwon, Yang-Hee; Kang, Sung-Hoon; Hong, Sung-Gul; Moon, Juhyuk

2017-02-24

Without using strong alkaline solution or ordinary Portland cement, a new structural binder consisting of fly ash and hydrated lime was hardened through an intensified pozzolanic reaction. The main experimental variables are the addition of silica fume and initial thermal treatment (60 °C for 3 days). A series of experiments consisting of mechanical testing (compressive and flexural strength, modulus of elasticity), X-ray diffraction, and measurements of the heat of hydration, pore structure, and shrinkage were conducted. These tests show that this new fly ash-based mortar has a compressive strength of 15 MPa at 91 days without any silica fume addition or initial thermal treatment. The strength increased to over 50 MPa based on the acceleration of the intensified pozzolanic reaction from the silica fume addition and initial thermal treatment. This is explained by a significant synergistic effect induced by the silica fume. It intensifies the pozzolanic reaction under thermal treatment and provides a space filling effect. This improved material performance can open a new pathway to utilize the industrial by-product of fly ash in cementless construction materials.

Mineral of the month: titanium

USGS Publications Warehouse

Gambogi, Joseph

2004-01-01

From paint to airplanes, titanium is important in a number of applications. Commercial production comes from titanium-bearing ilmenite, rutile and leucoxene (altered ilmenite). These minerals are used to produce titanium dioxide pigment, as well as an assortment of metal and chemical products.

[Follow-up examinations after removal of titanium plates coated with anodic titanium oxide ceramic].

PubMed

Velich, Norbert; Németh, Zsolt; Barabás, József; Szabó, György

2002-04-01

Transformation of the titanium metal surface with titanium oxides produced in various ways belongs among the most up-to-date procedures. The authors as pioneers in this field (e.g. Nobel Biocare TiUnite surface), have been utilizing for more than 15 years dental root implants and fixing elements (for mandibular osteosynthesis) coated with titanium oxide ceramics, produced by anodic oxidation and thermal treatment. The aim of this work was to assess the extent to which a titanium oxide ceramic coating influences the fate of plates applied for osteosynthesis within the human body. During a 5-year period (1995-1999), 108 of 1396 titanium oxide ceramic plates had to be removed for various reasons: loosening of the plate [47], osteomyelitis [25], a palpable swelling and tenderness [21] at the request of the patient for psychological reasons (13) or breaking of the plate [2]. When these 108 plates were removed, it was not possible to detect metallosis in even a single case; nor was there any tissue damage that could be attributed to the surface of the plates, whereas the literature data indicate that such damage is relatively frequent in the environment of traditional titanium fixing elements. The present investigation confirms the favourable properties of the titanium oxide ceramic surface.

Multi-objective optimization of swash plate forging process parameters for the die wear/service life improvement

NASA Astrophysics Data System (ADS)

Hu, X. F.; Wang, L. G.; Wu, H.; Liu, S. S.

2017-12-01

For the forging process of the swash plate, the author designed a kind of multi-index orthogonal experiment. Based on the Archard wear model, the influences of billet temperature, die temperature, forming speed, top die hardness and friction coefficient on forming load and die wear were numerically simulated by DEFORM software. Through the analysis of experimental results, the best forging process parameters were optimized and determined, which could effectively reduce the die wear and prolong the die service life. It is significant to increase the practical production of enterprise, especially to reduce the production cost and to promote enterprise profit.

Microstructure and corrosion behaviour in biological environments of the new forged low-Ni Co-Cr-Mo alloys.

PubMed

Hiromoto, Sachiko; Onodera, Emi; Chiba, Akihiko; Asami, Katsuhiko; Hanawa, Takao

2005-08-01

Corrosion behaviour and microstructure of developed low-Ni Co-29Cr-(6, 8)Mo (mass%) alloys and a conventional Co-29Cr-6Mo-1Ni alloy (ASTM F75-92) were investigated in saline solution (saline), Hanks' solution (Hanks), and cell culture medium (E-MEM + FBS). The forging ratios of the Co-29Cr-6Mo alloy were 50% and 88% and that of the Co-29Cr-8Mo alloy was 88%. Ni content in the air-formed surface oxide film of the low-Ni alloys was under the detection limit of XPS. The passive current densities of the low-Ni alloys were of the same order of magnitude as that of the ASTM alloy in all the solutions. The passive current densities of all the alloys did not significantly change with the inorganic ions and the biomolecules. The anodic current densities in the secondary passive region of the low-Ni alloys were lower than that of the ASTM alloy in the E-MEM + FBS. Consequently, the low-Ni alloys are expected to show as high corrosion resistance as the ASTM alloy. On the other hand, the passive current density of the Co-29Cr-6Mo alloy with a forging ratio of 50% was slightly lower than that with a forging ratio of 88% in the saline. The refining of grains by further forging causes the increase in the passive current density of the low-Ni alloy.

Fallon, Nevada FORGE Lithology Logs and Well 21-31 Drilling Data

DOE Data Explorer

Blankenship, Doug; Hinz, Nicholas; Faulds, James

2018-03-11

This submission includes lithology logs for all Fallon FORGE area wells; determined from core, cuttings, and thin section. Wells included are 84-31, 21-31, 82-36, FOH-3D, 62-36, 18-5, 88-24, 86-25, FOH-2, 14-36, 17-16, 34-33, 35A-11, 51A-20, 62-15, 72-7, 86-15, Carson_Strat_1_36-32, and several others. Lithology logs last updated 3/13/2018 with confirmation well 21-31 data, and revisited existing wells. Also included is well logging data for Fallon FORGE 21-31. Well logging data includes daily reports, well logs (drill rate, lithology, fractures, mud losses, minerals, temperature, gases, and descriptions), mud reports, drilling parameter plots, daily mud loss summaries, survey reports, progress reports, plan view maps (easting, northing), and wireline logs (caliper [with GR], triple combo [GR, caliper, SP, resistivity, array induction, density, photoelectric factor, and neutron porosity], array induction with linear correlation [GR, SP, Array Induction, caliper, conductivity], and monopole compression dipole shear [GR, SP, Caliper, sonic porosity, delta-T compressional, and delta-T shear])

Osseointegration is improved by coating titanium implants with a nanostructured thin film with titanium carbide and titanium oxides clustered around graphitic carbon.

PubMed

Veronesi, Francesca; Giavaresi, Gianluca; Fini, Milena; Longo, Giovanni; Ioannidu, Caterina Alexandra; Scotto d'Abusco, Anna; Superti, Fabiana; Panzini, Gianluca; Misiano, Carlo; Palattella, Alberto; Selleri, Paolo; Di Girolamo, Nicola; Garbarino, Viola; Politi, Laura; Scandurra, Roberto

2017-01-01

Titanium implants coated with a 500nm nanostructured layer, deposited by the Ion Plating Plasma Assisted (IPPA) technology, composed of 60% graphitic carbon, 25% titanium oxides and 15% titanium carbide were implanted into rabbit femurs whilst into the controlateral femurs uncoated titanium implants were inserted as control. At four time points the animals were injected with calcein green, xylenol orange, oxytetracycline and alizarin. After 2, 4 and 8weeks femurs were removed and processed for histology and static and dynamic histomorphometry for undecalcified bone processing into methylmethacrylate, sectioned, thinned, polished and stained with Toluidine blue and Fast green. The overall bone-implant contacts rate (percentage of bone-implant contacts/weeks) of the TiC coated implant was 1.6 fold than that of the uncoated titanium implant. The histomorphometric analyses confirmed the histological evaluations. More precisely, higher Mineral Apposition Rate (MAR, μm/day) (p<0.005) and Bone Formation Rate (BFR, μm 2 /μm/day) (p<0.0005) as well as Bone Implant Contact (Bic) and Bone Ingrowth values (p<0.0005) were observed for the TiC coated implants compared to uncoated implants. In conclusion the hard nanostructured TiC layer protects the bulk titanium implant against the harsh conditions of biological tissues and in the same time, stimulating adhesion, proliferation and activity of osteoblasts, induces a better bone-implant contacts of the implant compared to the uncoated titanium implant. Copyright © 2016. Published by Elsevier B.V.

Titanium Brazing for Structures and Survivability

DTIC Science & Technology

2007-05-01

materials, such as ceramics. This work focuses on vacuum brazing of titanium (both Ti- 6Al - 4V and commercially pure titanium ) and the effect of...such as ceramics. This work focuses on vacuum brazing of titanium (both Ti- 6Al - 4V and commercially pure titanium ) and the effect of processing...Suzumura, and Onzawa, reported the joining of Ti- 6Al - 4V and CP titanium alloys with zirconium-rich braze alloys.5 They found that these alloys could

Forging C-C Bonds Through Decarbonylation of Aryl Ketones.

PubMed

Somerville, Rosie J; Martin, Ruben

2017-06-06

The ability of nickel to cleave strong σ-bonds is again in the spotlight after a recent report that demonstrates the feasibility of using nickel complexes to promote decarbonylation of diaryl ketones. This transformation involves the cleavage of two strong C-C(O) bonds and avoids the use of noble metals, hence reinforcing the potential of decarbonylation as a technique for forging C-C bonds. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Application of multi-grid method on the simulation of incremental forging processes

NASA Astrophysics Data System (ADS)

Ramadan, Mohamad; Khaled, Mahmoud; Fourment, Lionel

2016-10-01

Numerical simulation becomes essential in manufacturing large part by incremental forging processes. It is a splendid tool allowing to show physical phenomena however behind the scenes, an expensive bill should be paid, that is the computational time. That is why many techniques are developed to decrease the computational time of numerical simulation. Multi-Grid method is a numerical procedure that permits to reduce computational time of numerical calculation by performing the resolution of the system of equations on several mesh of decreasing size which allows to smooth faster the low frequency of the solution as well as its high frequency. In this paper a Multi-Grid method is applied to cogging process in the software Forge 3. The study is carried out using increasing number of degrees of freedom. The results shows that calculation time is divide by two for a mesh of 39,000 nodes. The method is promising especially if coupled with Multi-Mesh method.

Tensile properties of titanium electrolytically charged with hydrogen

NASA Technical Reports Server (NTRS)

Smith, R. J.; Otterson, D. A.

1971-01-01

Yield strength, ultimate tensile strength, and elongation were studied for annealed titanium electrolytically charged with hydrogen. The hydrogen was present as a surface hydride layer. These tensile properties were generally lower for uncharged titanium than for titanium with a continuous surface hydride; they were greater for uncharged titanium than for titanium with an assumed discontinuous surface hydride. We suggest that the interface between titanium and titanium hydride is weak. And the hydride does not necessarily impair strength and ductility of annealed titanium. The possibility that oxygen and/or nitrogen can embrittle titanium hydride is discussed.

Fabrication of low-cost, cementless femoral stem 316L stainless steel using investment casting technique.

PubMed

Baharuddin, Mohd Yusof; Salleh, Sh-Hussain; Suhasril, Andril Arafat; Zulkifly, Ahmad Hafiz; Lee, Muhammad Hisyam; Omar, Mohd Afian; Abd Kader, Ab Saman; Mohd Noor, Alias; A Harris, Arief Ruhullah; Abdul Majid, Norazman

2014-07-01

Total hip arthroplasty is a flourishing orthopedic surgery, generating billions of dollars of revenue. The cost associated with the fabrication of implants has been increasing year by year, and this phenomenon has burdened the patient with extra charges. Consequently, this study will focus on designing an accurate implant via implementing the reverse engineering of three-dimensional morphological study based on a particular population. By using finite element analysis, this study will assist to predict the outcome and could become a useful tool for preclinical testing of newly designed implants. A prototype is then fabricated using 316L stainless steel by applying investment casting techniques that reduce manufacturing cost without jeopardizing implant quality. The finite element analysis showed that the maximum von Mises stress was 66.88 MPa proximally with a safety factor of 2.39 against endosteal fracture, and micromotion was 4.73 μm, which promotes osseointegration. This method offers a fabrication process of cementless femoral stems with lower cost, subsequently helping patients, particularly those from nondeveloped countries. Copyright © 2013 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Tracing Titanium Escape

NASA Image and Video Library

2015-05-07

The plot of data from NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR (right), amounts to a "smoking gun" of evidence in the mystery of how massive stars explode. The observations indicate that supernovae belonging to a class called Type II or core-collapse blast apart in a lopsided fashion, with the core of the star hurtling in one direction, and the ejected material mostly expanding the other way (see diagram in Figure 1). NuSTAR made the most precise measurements yet of a radioactive element, called titanium-44, in the supernova remnant called 1987A. NuSTAR sees high-energy X-rays, as shown here in the plot ranging from 60 to more than 80 kiloelectron volts. The spectral signature of titanium-44 is apparent as the two tall peaks. The white line shows where one would expect to see these spectral signatures if the titanium were not moving. The fact that the spectral peaks have shifted to lower energies indicates that the titanium has "redshifted," and is moving way from us. This is similar to what happens to a train's whistle as the train leaves the station. The whistle's sound shifts to lower frequencies. NuSTAR's detection of redshifted titanium reveals that the bulk of material ejected in the 1987A supernova is flying way from us at a velocity of 1.6 million miles per hour (2.6 million kilometers per hour). Had the explosion been spherical in nature, the titanium would have been seen flying uniformly in all directions. This is proof that this explosion occurred in an asymmetrical fashion. http://photojournal.jpl.nasa.gov/catalog/PIA19335

Titanium fasteners. [for aircraft industry

NASA Technical Reports Server (NTRS)

Phillips, J. L.

1972-01-01

Titanium fasteners are used in large quantities throughout the aircraft industry. Most of this usage is in aluminum structure; where titanium structure exists, titanium fasteners are logically used as well. Titanium fasteners offer potential weight savings to the designer at a cost of approximately $30 per pound of weight saved. Proper and least cost usage must take into consideration type of fastener per application, galvanic couples and installation characteristics of protective coatings, cosmetic appearance, paint adhesion, installation forces and methods available and fatigue performance required.

The hydrogen embrittlement of titanium-based alloys

NASA Astrophysics Data System (ADS)

Tal-Gutelmacher, Ervin; Eliezer, Dan

2005-09-01

Titanium-based alloys provide an excellent combination of a high strength/weight ratio and good corrosion behavior, which makes these alloys among the most important advanced materials for a variety of aerospace, marine, industrial, and commercial applications. Although titanium is considered to be reasonably resistant to chemical attack, severe problems can arise when titanium-based alloys come in contact with hydrogen-containing environments, where they can pick up large amounts of hydrogen, especially at elevated temperatures. The severity and the extent of the hydrogen interaction with titanium-based alloys are directly related to the microstructure and composition of the titanium alloys. This paper addresses the hydrogen embrittlement of titanium-based alloys. The hydrogen-titanium interaction is reviewed, including the solubility of hydrogen in α and β phases of titanium and hydride formation. Also, the paper summarizes the detrimental effects of hydrogen in different titanium alloys.

Optimization of custom cementless stem using finite element analysis and elastic modulus distribution for reducing stress-shielding effect.

PubMed

Saravana Kumar, Gurunathan; George, Subin Philip

2017-02-01

This work proposes a methodology involving stiffness optimization for subject-specific cementless hip implant design based on finite element analysis for reducing stress-shielding effect. To assess the change in the stress-strain state of the femur and the resulting stress-shielding effect due to insertion of the implant, a finite element analysis of the resected femur with implant assembly is carried out for a clinically relevant loading condition. Selecting the von Mises stress as the criterion for discriminating regions for elastic modulus difference, a stiffness minimization method was employed by varying the elastic modulus distribution in custom implant stem. The stiffness minimization problem is formulated as material distribution problem without explicitly penalizing partial volume elements. This formulation enables designs that could be fabricated using additive manufacturing to make porous implant with varying levels of porosity. Stress-shielding effect, measured as difference between the von Mises stress in the intact and implanted femur, decreased as the elastic modulus distribution is optimized.

Numerical assessment of bone remodeling around conventionally and early loaded titanium and titanium-zirconium alloy dental implants.

PubMed

Akça, Kıvanç; Eser, Atılım; Çavuşoğlu, Yeliz; Sağırkaya, Elçin; Çehreli, Murat Cavit

2015-05-01

The aim of this study was to investigate conventionally and early loaded titanium and titanium-zirconium alloy implants by three-dimensional finite element stress analysis. Three-dimensional model of a dental implant was created and a thread area was established as a region of interest in trabecular bone to study a localized part of the global model with a refined mesh. The peri-implant tissues around conventionally loaded (model 1) and early loaded (model 2) implants were implemented and were used to explore principal stresses, displacement values, and equivalent strains in the peri-implant region of titanium and titanium-zirconium implants under static load of 300 N with or without 30° inclination applied on top of the abutment surface. Under axial loading, principal stresses in both models were comparable for both implants and models. Under oblique loading, principal stresses around titanium-zirconium implants were slightly higher in both models. Comparable stress magnitudes were observed in both models. The displacement values and equivalent strain amplitudes around both implants and models were similar. Peri-implant bone around titanium and titanium-zirconium implants experiences similar stress magnitudes coupled with intraosseous implant displacement values under conventional loading and early loading simulations. Titanium-zirconium implants have biomechanical outcome comparable to conventional titanium implants under conventional loading and early loading.

Titanium hydride and hydrogen concentration in acid-etched commercially pure titanium and titanium alloy implants: a comparative analysis of five implant systems.

PubMed

Szmukler-Moncler, S; Bischof, M; Nedir, R; Ermrich, M

2010-09-01

Acid etching is a popular method to texture the surface of dental implants. During etching, the titanium oxide protective layer is dissolved and small native hydrogen ions diffuse into the unprotected implant surface. They enrich the implant surface with hydrogen and precipitate into titanium hydride (TiH). The aim of this study was to measure the concentration of TiH at the implant surface and the total concentration of Hydrogen at five commercially available implant systems, made of either commercially pure (cp) titanium or titanium alloy. X-Ray diffraction (XRD) was conducted on each implant system to determine the compounds present at the implant surface. Following a TiH(2)/Ti calibration curve, the concentration of TiH was determined. Concentration of hydrogen in the implants was measured by the inert gas fusion thermal conductivity/infrared detection method. XRD data showed that TiH was present on all cp titanium implants but not on the alloyed implants. TiH concentration varied between 5% and 37%. Hydrogen concentration varied between 43 and 108 ppm, no difference in uptake was found between the cp titanium and alloyed implants. Low solubility of hydrogen in alpha-titanium is responsible for precipitation into TiH. Stronger etching conditions led to higher concentration of TiH2-x. High solubility of hydrogen in the beta-phase of the alloy is preventing hydrogen from precipitating into TiH. All implants, even those lacking TiH at the surface, were enriched with hydrogen. In all implants, hydrogen concentration was within the normative limit of 130 ppm.

The Influence of Temperature on the Frictional Behavior of Duplex-Coated Die Steel Rubbing Against Forging Brass

NASA Astrophysics Data System (ADS)

Ebrahimzadeh, I.; Ashrafizadeh, F.

2015-01-01

Improvement of die life under hot forging of brass alloys is considered vital from both economical and technical points of view. One of the best methods for improving die life is duplex coatings. In this research, the influence of temperature on the tribological behavior of duplex-coated die steel rubbing against forging brass was investigated. The wear tests were performed on a pin-on-disk machine from room temperature to 700 °C; the pins were made in H13 hot work tool steel treated by plasma nitriding and by PVD coatings of TiN-TiAlN-CrAlN. The disks were machined from a two-phase brass alloy too. The results revealed that the friction coefficient of this tribosystem went through a maximum at 550 °C and decreased largely at 700 °C. Furthermore, the formation of Cr2O3 caused the reduction of friction coefficient at 700 °C. PVD coatings proved their wear resistance up to 550 °C, well above the working temperature of the brass forging dies.

Simulations and Experiments of the Nonisothermal Forging Process of a Ti-6Al-4V Impeller

NASA Astrophysics Data System (ADS)

Prabhu, T. Ram

2016-09-01

In the present study, a nonisothermal precision forging process of a Ti-6Al-4V first-stage impeller for the gas turbine engine was simulated using the finite element software. The simulation results such as load requirements, damage, velocity field, stress, strain, and temperature distributions are discussed in detail. Simulations predicted the maximum load requirement of about 80 MN. The maximum temperature loss was observed at the contour surface regions. The center and contour regions are the high-strained regions in the part. To validate the model, forging experiments mimicking simulations were performed in the α + β phases region (930 °C). The selected locations of the part were characterized for tensile properties at 27 and 200 °C, hardness, microstructure, grain size, and the amount of primary α phase based on the strain distribution results. The soundness of the forged part was verified using fluorescent penetrant test (Mil Std 2175 Grade A) and ultrasonic test (AMS 2630 class A1). From the experimental results, it was found that the variations in the hardness, tensile properties at room, and elevated temperature are not significant. The microstructure, grain size, and primary α phase content are nearly same.

[Research on the temperature field detection method of hot forging based on long-wavelength infrared spectrum].

PubMed

Zhang, Yu-Cun; Wei, Bin; Fu, Xian-Bin

2014-02-01

A temperature field detection method based on long-wavelength infrared spectrum for hot forging is proposed in the present paper. This method combines primary spectrum pyrometry and three-stage FP-cavity LCTF. By optimizing the solutions of three group nonlinear equations in the mathematical model of temperature detection, the errors are reduced, thus measuring results will be more objective and accurate. Then the system of three-stage FP-cavity LCTF was designed on the principle of crystal birefringence. The system realized rapid selection of any wavelength in a certain wavelength range. It makes the response of the temperature measuring system rapid and accurate. As a result, without the emissivity of hot forging, the method can acquire exact information of temperature field and effectively suppress the background light radiation around the hot forging and ambient light that impact the temperature detection accuracy. Finally, the results of MATLAB showed that the infrared spectroscopy through the three-stage FP-cavity LCTF could meet the requirements of design. And experiments verified the feasibility of temperature measuring method. Compared with traditional single-band thermal infrared imager, the accuracy of measuring result was improved.

Process for reproducibly preparing titanium subhydride

DOEpatents

Carlson, Richard S.

1982-01-01

Titanium subhydride is produced in a reactor by heating a selected amount of finely divided titanium compound at a selected temperature for a selected period of time under dynamic vacuum conditions. Hydrogen is removed substantially uniformly from each powder grain and there is produced a subhydride of substantially uniform titanium-hydrogen composition. Selection of the amount, temperature and time produces a subhydride of selected titanium-hydrogen composition.

Correlating Scatter in Fatigue Life with Fracture Mechanisms in Forged Ti-6242Si Alloy

NASA Astrophysics Data System (ADS)

Sinha, V.; Pilchak, A. L.; Jha, S. K.; Porter, W. J.; John, R.; Larsen, J. M.

2018-04-01

Unlike the quasi-static mechanical properties, such as strength and ductility, fatigue life can vary significantly (by an order of magnitude or more) for nominally identical material and test conditions in many materials, including Ti-alloys. This makes life prediction and management more challenging for components that are subjected to cyclic loading in service. The differences in fracture mechanisms can cause the scatter in fatigue life. In this study, the fatigue fracture mechanisms were investigated in a forged near- α titanium alloy, Ti-6Al-2Sn-4Zr-2Mo-0.1Si, which had been tested under a condition that resulted in life variations by more than an order of magnitude. The crack-initiation and small crack growth processes, including their contributions to fatigue life variability, were elucidated via quantitative characterization of fatigue fracture surfaces. Combining the results from quantitative tilt fractography and electron backscatter diffraction, crystallography of crack-initiating and neighboring facets on the fracture surface was determined. Cracks initiated on the surface for both the shortest and the longest life specimens. The facet plane in the crack-initiating grain was aligned with the basal plane of a primary α grain for both the specimens. The facet planes in grains neighboring the crack-initiating grain were also closely aligned with the basal plane for the shortest life specimen, whereas the facet planes in the neighboring grains were significantly misoriented from the basal plane for the longest life specimen. The difference in the extent of cracking along the basal plane can explain the difference in fatigue life of specimens at the opposite ends of scatter band.

Utah FORGE Gravity Data Shapefile

DOE Data Explorer

Joe Moore

2016-03-13

This is a zipped GIS compatible shapefile of gravity data points used in the Milford, Utah FORGE project as of March 21st, 2016. The shapefile is native to ArcGIS, but can be used with many GIS software packages. Additionally, there is a .dbf (dBase) file that contains the dataset which can be read with Microsoft Excel. The Data was downloaded from the PACES (Pan American Center for Earth and Environmental Studies) hosted by University of Texas El Paso (http://research.utep.edu/Default.aspx?alias=research.utep.edu/paces) Explanation:Source: data source code if available LatNAD83: latitude in NAD83 [decimal degrees] LonNAD83: longitude in NAD83 [decimal degrees]zWGS84: elevation in WGS84 (ellipsoidal) [m]OBSless976: observed gravity minus 976000 mGalIZTC: inner zone terrain correction [mGal]OZTC: outer zone terrain correction [mGal]FA: Free Air anomaly value [mGal]CBGA: Complete Bouguer gravity anomaly value [mGal

Titanium: light, strong, and white

USGS Publications Warehouse

Woodruff, Laurel; Bedinger, George

2013-01-01

Titanium (Ti) is a strong silver-gray metal that is highly resistant to corrosion and is chemically inert. It is as strong as steel but 45 percent lighter, and it is twice as strong as aluminum but only 60 percent heavier. Titanium dioxide (TiO2) has a very high refractive index, which means that it has high light-scattering ability. As a result, TiO2 imparts whiteness, opacity, and brightness to many products. ...Because of the unique physical properties of titanium metal and the whiteness provided by TiO2, titanium is now used widely in modern industrial societies.

Characterization of a Viking Blade Fabricated by Traditional Forging Techniques

NASA Astrophysics Data System (ADS)

Vo, H.; Frazer, D.; Bailey, N.; Traylor, R.; Austin, J.; Pringle, J.; Bickel, J.; Connick, R.; Connick, W.; Hosemann, P.

2016-12-01

A team of students from the University of California, Berkeley, participated in a blade-smithing competition hosted by the Minerals, Metals, and Materials Society at the TMS 2015 144th annual meeting and exhibition. Motivated by ancient forging methods, the UC Berkeley team chose to fabricate our blade from historical smithing techniques utilizing naturally-occurring deposits of iron ore. This approach resulted in receiving the "Best Example of a Traditional Blade Process/Ore Smelting Technique" award for our blade named "Berkelium." First, iron-enriched sand was collected from local beaches. Magnetite (Fe3O4) was then extracted from the sand and smelted into individual high- and low-carbon steel ingots. Layers of high- and low-carbon steels were forge-welded together, predominantly by hand, to form a composite material. Optical microscopy, energy dispersive spectroscopy, and Vickers hardness mechanical testing were conducted at different stages throughout the blade-making process to evaluate the microstructure and hardness evolution during formation. It was found that the pre-heat-treated blade microstructure was composed of ferrite and pearlite, and contained many nonmetallic inclusions. A final heat treatment was performed, which caused the average hardness of the blade edge to increase by more than a factor of two, indicating a martensitic transformation.

Method of manufacturing corrosion resistant tubing from welded stock of titanium or titanium base alloy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meredith, S.E.; Benjamin, J.F.

1993-07-13

A method is described of manufacturing corrosion resistant tubing from seam welded stock of a titanium or titanium based alloy, comprising: cold pilgering a seam welded tube hollow of titanium or titanium based alloy in a single pass to a final sized tubing, the tube hollow comprising a strip which has been bent and welded along opposed edges thereof to form the tube hollow, the tube hollow optionally being heat treated prior to the cold pilgering step provided the tube hollow is not heated to a temperature which would transform the titanium or titanium alloy into the beta phase, themore » cold pilgering effecting a reduction in cross sectional area of the tube hollow of at least 50% and a reduction of wall thickness of at least 50%, in order to achieve a radially oriented crystal structure; and annealing the final sized tubing at a temperature and time sufficient to effect complete recrystallization and reform grains in a weld area along the seam into smaller, homogeneous grains.« less

Sprayable titanium composition

DOEpatents

Tracy, Chester E.; Kern, Werner; Vibronek, Robert D.

1980-01-01

The addition of 2-ethyl-1-hexanol to an organometallic titanium compound dissolved in a diluent and optionally containing a lower aliphatic alcohol spreading modifier, produces a solution that can be sprayed onto a substrate and cured to form an antireflection titanium oxide coating having a refractive index of from about 2.0 to 2.2.

Clinical results of Hi-tech Knee II total knee arthroplasty in patients with rheumatoid athritis: 5- to 12-year follow-up

PubMed Central

2012-01-01

Background Total knee arthroplasty (TKA) is a common form of treatment to relieve pain and improve function in cases of rheumatoid arthritis (RA). Good clinical outcomes have been reported with a variety of TKA prostheses. The cementless Hi-Tech Knee II cruciate-retaining (CR)-type prosthesis, which has 6 fins at the anterior of the femoral component, posterior cruciate ligament (PCL) retention, flat-on-flat surface component geometry, all-polyethylene patella, strong initial fixation by the center screw of the tibial base plate, 10 layers of titanium alloy fiber mesh, and direct compression molded ultra high molecular weight polyethylene (UHMWPE), is appropriate for TKA in the Japanese knee. The present study was performed to evaluate the clinical results of primary TKA in RA using the cementless Hi-Tech Knee II CR-type prosthesis. Materials and methods We performed 32 consecutive primary TKAs using cementless Hi-Tech Knee II CR-type prosthesis in 31 RA patients. The average follow-up period was 8 years 3 months. Clinical evaluations were performed according to the American Knee Society (KS) system, knee score, function score, radiographic evaluation, and complications. Results The mean postoperative maximum flexion angle was 115.6°, and the KS knee score and function score improved to 88 and 70 after surgery, respectively. Complications, such as infection, occurred in 1 patient and revision surgery was performed. There were no cases of loosening in this cohort, and prosthesis survival rate was 96.9% at 12 years postoperatively. Conclusion These results suggest that TKA using the cementless Hi-Tech Knee II CR-type prosthesis is a very effective form of treatment in RA patients at 5 to 12 years postoperatively. Further long-term follow-up studies are required to determine the ultimate utility of this type of prosthesis. PMID:22356935

Clinical results of Hi-tech Knee II total knee arthroplasty in patients with rheumatoid athritis: 5- to 12-year follow-up.

PubMed

Yamanaka, Hajime; Goto, Ken-ichiro; Suzuki, Munetaka

2012-02-22

Total knee arthroplasty (TKA) is a common form of treatment to relieve pain and improve function in cases of rheumatoid arthritis (RA). Good clinical outcomes have been reported with a variety of TKA prostheses. The cementless Hi-Tech Knee II cruciate-retaining (CR)-type prosthesis, which has 6 fins at the anterior of the femoral component, posterior cruciate ligament (PCL) retention, flat-on-flat surface component geometry, all-polyethylene patella, strong initial fixation by the center screw of the tibial base plate, 10 layers of titanium alloy fiber mesh, and direct compression molded ultra high molecular weight polyethylene (UHMWPE), is appropriate for TKA in the Japanese knee.The present study was performed to evaluate the clinical results of primary TKA in RA using the cementless Hi-Tech Knee II CR-type prosthesis. We performed 32 consecutive primary TKAs using cementless Hi-Tech Knee II CR-type prosthesis in 31 RA patients. The average follow-up period was 8 years 3 months. Clinical evaluations were performed according to the American Knee Society (KS) system, knee score, function score, radiographic evaluation, and complications. The mean postoperative maximum flexion angle was 115.6°, and the KS knee score and function score improved to 88 and 70 after surgery, respectively. Complications, such as infection, occurred in 1 patient and revision surgery was performed. There were no cases of loosening in this cohort, and prosthesis survival rate was 96.9% at 12 years postoperatively. These results suggest that TKA using the cementless Hi-Tech Knee II CR-type prosthesis is a very effective form of treatment in RA patients at 5 to 12 years postoperatively. Further long-term follow-up studies are required to determine the ultimate utility of this type of prosthesis.

Seismic Data from Roosevelt Hot Springs, Utah FORGE Study Area

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, John

This set of data contains raw and processed 2D and 3D seismic data from the Utah FORGE study area near Roosevelt Hot Springs. The zipped archives numbered from 1-100 to 1001-1122 contain 3D seismic uncorrelated shot gatherers SEG-Y files. The zipped archives numbered from 1-100C to 1001-1122C contain 3D seismic correlated shot gatherers SEG-Y files. Other data have intuitive names.

A New Construction Material-Titanium

DTIC Science & Technology

1974-01-01

results of studying the electrochemical behavior of titanium and its alloys in aggressive media, and also the oxidizability of the most important...are the following properties of titanium and especially its alloys: low specific weight, high strength, corrosion resistance in many agressive media...resistance or complete immunity of titanium to a number of agressive media. 3. Operational directions: a) lengthening the service life of the articles, b

Process for making a titanium diboride-chromium diboride-yttrium titanium oxide ceramic composition

DOEpatents

Holcombe, Cressie E.; Dykes, Norman L.

1992-01-01

A ceramic composition composition is described. The ceramic composition consists essentially of from about 84 to 96 w/o titanium diboride, from about 1 to 9 w/o chromium diboride, and from about 3 to aobut 15 w/o yttrium-titanium-oxide. A method of making the ceramic composition is also described. The method of making the ceramic composition comprises the following steps: Step 1--A consolidated body containing stoichiometric quantities of titanium diboride and chromium diboride is provided. Step 2--The consolidated body is enclosed in and in contact with a thermally insulated package of yttria granules having a thickness of at least 0.5 inches. Step 3--The consolidated body enclosed in the thermally insulated package of yttria granules is heated in a microwave oven with microwave energy to a temperature equal to or greater than 1,900 degrees centigrade to sinter and uniformly disperse yttria particles having a size range from about 1 to about 12 microns throughout the consolidated body forming a densified body consisting essentially of titanium diboride, chromium diboride, and yttrium-titanium-oxide. The resulting densified body has enhanced fracture toughness and hardness.

Process for making a titanium diboride-chromium diboride-yttrium titanium oxide ceramic composition

DOEpatents

Holcombe, C.E.; Dykes, N.L.

1992-04-28

A ceramic composition is described. The ceramic composition consists essentially of from about 84 to 96 w/o titanium diboride, from about 1 to 9 w/o chromium diboride, and from about 3 to about 15 w/o yttrium-titanium-oxide. A method of making the ceramic composition is also described. The method of making the ceramic composition comprises the following steps: Step 1--A consolidated body containing stoichiometric quantities of titanium diboride and chromium diboride is provided. Step 2--The consolidated body is enclosed in and in contact with a thermally insulated package of yttria granules having a thickness of at least 0.5 inches. Step 3--The consolidated body enclosed in the thermally insulated package of yttria granules is heated in a microwave oven with microwave energy to a temperature equal to or greater than 1,900 degrees centigrade to sinter and uniformly disperse yttria particles having a size range from about 1 to about 12 microns throughout the consolidated body forming a densified body consisting essentially of titanium diboride, chromium diboride, and yttrium-titanium-oxide. The resulting densified body has enhanced fracture toughness and hardness. No Drawings

Early radiological and functional outcomes for a cementless press-fit design modular femoral stem revision system.

PubMed

Hancock, Douglas S; Sharplin, Paul K; Larsen, Peter D; Phillips, Fredrick Ts

2018-05-01

To assess early radiological and functional outcomes of revision hip surgery with a cementless press-fit design femoral stem. A retrospective review of 48 consecutive revision total hip replacements using the RECLAIM revision hip system, between October 2012 and August 2015. Radiographic assessment was undertaken with serial anteroposterior (AP) X-rays of the pelvis. Risk factors for subsidence were evaluated. Prospective clinical follow up was performed on 21 patients to assess functional outcomes. Mean stem subsidence was 1.1 mm (95% confidence interval[CI]: 0.63-1.57). Median follow up of 12 months. An inverse relationship was observed between level of subsidence and femoral stem diameter r = -0.45, p = 0.001. Subsidence at the time of follow-up assessment was correlated with initial subsidence (correlation coefficient rho 0.69, p = 0.001). The mean Merle d'Aubigne score at the latest follow up was 14.2 (range 8-17). The mean OHS was 34.1 (range 15-48). Early radiological and functional outcomes for the RECLAIM revision system showed very low levels of subsidence and good functional outcomes. There was an association with smaller diameter femoral stems and greater levels of subsidence.

40 CFR 180.1195 - Titanium dioxide.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Titanium dioxide. 180.1195 Section 180.1195 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS... Titanium dioxide. Titanium dioxide is exempted from the requirement of a tolerance for residues in or on...

40 CFR 180.1195 - Titanium dioxide.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Titanium dioxide. 180.1195 Section 180.1195 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS... Titanium dioxide. Titanium dioxide is exempted from the requirement of a tolerance for residues in or on...

40 CFR 180.1195 - Titanium dioxide.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Titanium dioxide. 180.1195 Section 180.1195 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS... Titanium dioxide. Titanium dioxide is exempted from the requirement of a tolerance for residues in or on...

Effect of solution treatment on stress corrosion cracking behavior of an as-forged Mg-Zn-Y-Zr alloy

PubMed Central

Wang, S. D.; Xu, D. K.; Wang, B. J.; Sheng, L. Y.; Han, E. H.; Dong, C.

2016-01-01

Effect of solid solution treatment (T4) on stress corrosion cracking (SCC) behavior of an as-forged Mg-6.7%Zn-1.3%Y-0.6%Zr (in wt.%) alloy has been investigated using slow strain rate tensile (SSRT) testing in 3.5 wt.% NaCl solution. The results demonstrated that the SCC susceptibility index (ISCC) of as-forged samples was 0.95 and its elongation-to-failure (εf) was only 1.1%. After T4 treatment, the SCC resistance was remarkably improved. The ISCC and εf values of T4 samples were 0.86 and 3.4%, respectively. Fractography and surface observation indicated that the stress corrosion cracking mode for as-forged samples was dominated by transgranular and partially intergranular morphology, whereas the cracking mode for T4 samples was transgranular. In both cases, the main cracking mechanism was associated with hydrogen embrittlement (HE). Through alleviating the corrosion attack of Mg matrix, the influence of HE on the SCC resistance of T4 samples can be greatly suppressed. PMID:27387817

A Method for Measuring the Hardness of the Surface Layer on Hot Forging Dies Using a Nanoindenter

NASA Astrophysics Data System (ADS)

Mencin, P.; van Tyne, C. J.; Levy, B. S.

2009-11-01

The properties and characteristics of the surface layer of forging dies are critical for understanding and controlling wear. However, the surface layer is very thin, and appropriate property measurements are difficult to obtain. The objective of the present study is to determine if nanoindenter testing provides a reliable method, which could be used to measure the surface hardness in forging die steels. To test the reliability of nanoindenter testing, nanoindenter values for two quenched and tempered steels (FX and H13) are compared to microhardness and macrohardness values. These steels were heat treated for various times to produce specimens with different values of hardness. The heat-treated specimens were tested using three different instruments—a Rockwell hardness tester for macrohardness, a Vickers hardness tester for microhardness, and a nanoindenter tester for fine scale evaluation of hardness. The results of this study indicate that nanoindenter values obtained using a Nanoindenter XP Machine with a Berkovich indenter reliably correlate with Rockwell C macrohardness values, and with Vickers HV microhardness values. Consequently, nanoindenter testing can provide reliable results for analyzing the surface layer of hot forging dies.

Increasing of the lifetime of large forging dies by repairwelding

NASA Astrophysics Data System (ADS)

Duchek, M.; Koukolikova, M.; Kotous, J.; Majer, M.

2018-02-01

Repair welding is often used for rebuilding discarded or failed forging dies. It saves the cost of new tools. Increased useful life of repaired dies is another motivation for repair welding. This article focuses on the development of new filler materials for this purpose. The main goal was to prolong the life of tools of DIN 1.2714 material. Filler wires of two chemistries were made and several samples were experimentally welded. Metallographic and tribological analyses were carried out.

Wear at the titanium-titanium and the titanium-zirconia implant-abutment interface: a comparative in vitro study.

PubMed

Stimmelmayr, Michael; Edelhoff, Daniel; Güth, Jan-Frederik; Erdelt, Kurt; Happe, Arndt; Beuer, Florian

2012-12-01

The purpose of this study was to determine and measure the wear of the interface between titanium implants and one-piece zirconia abutments in comparison to titanium abutments. 6 implants were secured into epoxy resin blocks. The implant interface of these implants and 6 corresponding abutments (group Zr: three one-piece zirconia abutments; group Ti: three titanium abutments) were examined by a microscope and scanning electron micrograph (SEM). Also the implants and the abutments were scanned by 3D-Micro Computer Tomography (CT). The abutments were connected to the implants and cyclically loaded with 1,200,000 cycles at 100N in a two-axis fatigue testing machine. Afterwards, all specimens were unscrewed and the implants and abutments again were scanned by microscope, SEM and CT. The microscope and SEM images were compared, the CT data were superimposed and the wear was calculated by inspection software. The statistical analysis was carried out with an unpaired t-test. Abutment fracture or screw loosening was not observed during cyclical loading. Comparing the microscope and SEM images more wear was observed on the implants connected to zirconia abutments. The maximum wear on the implant shoulder calculated by the inspection software was 10.2μm for group Zr, and 0.7μm for group Ti. The influence of the abutment material on the measured wear was statistically significant (p≤0.001; Levene-test). Titanium implants showed higher wear at the implant interface following cyclic loading when connected to one-piece zirconia implant abutments compared to titanium abutments. The clinical relevance is not clear; hence damage of the internal implant connection could result in prosthetic failures up to the need of implant removal. Copyright © 2012 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

THA Using Metal-on-Metal Articulation in Active Patients Younger Than 50 Years

PubMed Central

Bonnomet, François; Clavert, Philippe; Laffargue, Philippe; Migaud, Henri

2008-01-01

The main concern of patients with longer life expectancies and of patients who are younger and more active is the longevity of their total hip arthroplasty. We retrospectively reviewed 83 cementless total hip arthroplasties in 73 patients implanted with metal-on-metal articulation. All patients were younger than 50 years old (average age, 41 years) at the time of the index procedure, and 80% of the patients had an activity level graded 4 or 5 when measured with the system of Devane et al. A 28-mm Metasul articulation was used with three different cementless titanium acetabular components. At the most recent followup (average, 7.3 years), the average Merle d’Aubigné-Postel score improved from a preoperative 11.1 points to 17.4 points. We observed no radiographic evidence of component loosening. Ten acetabular components had lucency limited to one zone. The 10-year survivorship with the end point of revision (ie, exchange of at least one prosthetic or bearing component) was 100% (95% confidence interval, 90%–100%). Metasul bearings with cementless acetabular components remain promising in this high-risk younger patient population. However, additional followup strategies are recommended to determine any possible long-term deleterious effects associated with the dissemination of metallic ions. Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence. PMID:18196415

21 CFR 73.1575 - Titanium dioxide.

Code of Federal Regulations, 2010 CFR

2010-04-01

... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1575 Titanium dioxide. (a) Identity and specifications. (1) The color additive titanium dioxide shall conform in identity and specifications to the requirements of § 73.575(a)(1) and (b). (2) Color additive mixtures for drug use made with titanium dioxide may...

21 CFR 73.1575 - Titanium dioxide.

Code of Federal Regulations, 2012 CFR

2012-04-01

... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1575 Titanium dioxide. (a) Identity and specifications. (1) The color additive titanium dioxide shall conform in identity and specifications to the requirements of § 73.575(a)(1) and (b). (2) Color additive mixtures for drug use made with titanium dioxide may...

21 CFR 73.1575 - Titanium dioxide.

Code of Federal Regulations, 2013 CFR

2013-04-01

... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1575 Titanium dioxide. (a) Identity and specifications. (1) The color additive titanium dioxide shall conform in identity and specifications to the requirements of § 73.575(a)(1) and (b). (2) Color additive mixtures for drug use made with titanium dioxide may...

21 CFR 73.1575 - Titanium dioxide.

Code of Federal Regulations, 2014 CFR

2014-04-01

... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1575 Titanium dioxide. (a) Identity and specifications. (1) The color additive titanium dioxide shall conform in identity and specifications to the requirements of § 73.575(a)(1) and (b). (2) Color additive mixtures for drug use made with titanium dioxide may...

Experimental and numerical research on forging with torsion

NASA Astrophysics Data System (ADS)

Petrov, Mikhail A.; Subich, Vadim N.; Petrov, Pavel A.

2017-10-01

Increasing the efficiency of the technological operations of blank production is closely related to the computer-aided technologies (CAx). On the one hand, the practical result represents reality exactly. On the other hand, the development procedure of new process development demands unrestricted resources, which are limited on the SMEs. The tools of CAx were successfully applied for development of new process of forging with torsion and result analysis as well. It was shown, that the theoretical calculations find the confirmation both in praxis and during numerical simulation. The mostly used constructional materials were under study. The torque angles were stated. The simulated results were evaluated by experimental procedure.

Application of sintered titanium alloys to metal denture bases: a study of titanium powder sheets for complete denture base.

PubMed

Doi, H; Harrori, M; Hasegawa, K; Yoshinari, M; Kawada, E; Oda, Y

2001-02-01

The purpose of this study was the fabrication of titanium powder sheets to enable the application of sintered titanium alloys as metal denture bases. The effects of titanium particle shape and size, binder content, and plasticizer content on the surface smoothness, tensile strength and elongation of titanium powder sheets was investigated. To select a suitable ratio of powdered metal contents for application as a metal denture base, the effects of aluminum content in Ti sheets and various other powder metal contents in Ti-Al sheets on the density, sintering shrinkage, and bending strength were evaluated. Based on the results of the above experiments, we developed a mixed powder sheet composed of 83Ti-7Al-10Cr with TA45 titanium powder (atomized, -45 microm), and 8 mass% binder content. This titanium alloy sheet had good formability and ductility. Its sintered titanium alloy had a density of 3.2 g/cm3, sintering shrinkage of 3.8%, and bending strength of 403 MPa. The titanium alloy sheet is clinically acceptable for fabricating denture bases.

Joining of Gamma Titanium Aluminides

DTIC Science & Technology

2002-09-01

AFRL-ML-WP-TR-2003-4036 JOINING OF GAMMA TITANIUM ALUMINIDES LTC William A. Baeslack, III Metals Branch (AFRL/MLLM) Metals, Ceramics, and...GAMMA TITANIUM ALUMINIDES 5c. PROGRAM ELEMENT NUMBER 62102F 5d. PROJECT NUMBER MO2R 5e. TASK NUMBER 10 6. AUTHOR(S) LTC William A...comparatively discusses the results of research and development performed on the joining of gamma titanium aluminides during the past two decades. Although

Adhesive-Bonded Tab Attaches Thermocouples to Titanium

NASA Technical Reports Server (NTRS)

Cook, C. F.

1982-01-01

Mechanical strength of titanium-alloy structures that support thermocouples is preserved by first spotwelding thermocouples to titanium tabs and then attaching tabs to titanium with a thermosetting adhesive. In contrast to spot welding, a technique previously used for thermocouples, fatigue strength of the titanium is unaffected by adhesive bonding. Technique is also gentler than soldering or attaching thermocouples with a tap screw.

Corrosion resistance of nanostructured titanium.

PubMed

Garbacz, H; Pisarek, M; Kurzydłowski, K J

2007-11-01

The present work reports results of studies of corrosion resistance of pure nano-Ti-Grade 2 after hydrostatic extrusion. The grain size of the examined samples was below 90 nm. Surface analytical technique including AES combined with Ar(+) ion sputtering, were used to investigate the chemical composition and thicknesses of the oxides formed on nano-Ti. It has been found that the grain size of the titanium substrate did not influence the thickness of oxide formed on the titanium. The thickness of the oxide observed on the titanium samples before and after hydrostatic extrusion was about 6 nm. Tests carried out in a NaCl solution revealed a slightly lower corrosion resistance of nano-Ti in comparison with the titanium with micrometric grain size.

Structural characterization of oxidized titanium surfaces

NASA Astrophysics Data System (ADS)

Jobin, M.; Taborelli, M.; Descouts, P.

1995-05-01

Oxidized titanium surfaces resulting from various processes have been structurally characterized by means of scanning force microscopy, x-ray photoemission spectroscopy (XPS), x-ray diffraction, and electron energy-loss spectroscopy (EELS) with losses in the 0-100 eV range. It has been found that the surface morphology has a granular structure for electropolished titanium and for titanium evaporated on mica at low substrate temperature (570 K), but changes to flat terraces for the films evaporated at higher temperature (770 K). Angular-dependent XPS has revealed the presence of a Ti2O3 suboxide at the Ti/TiO2 interface for electropolished titanium. Dry oxidation has been performed at 770 and 970 K on both weakly and highly crystallized evaporated titanium films oriented along (0001). In the case of underlying crystallized metallic titanium, the resulting TiO2 films are crystallized with the anatase (004) orientation for oxidation at 770 K and with rutile (200) orientation for oxidation at 970 K. EELS spectra interpreted in terms of the molecular orbitals of a (TiO6)8- cluster show that the local octahedral environment of titanium atoms is preserved on native oxides, even if these oxides are not crystallized.

Forging Alliances in Interdisciplinary Rehabilitation Research (FAIRR): A Logic Model.

PubMed

Gill, Simone V; Khetani, Mary A; Yinusa-Nyahkoon, Leanne; McManus, Beth; Gardiner, Paula M; Tickle-Degnen, Linda

2017-07-01

In a patient-centered care era, rehabilitation can benefit from researcher-clinician collaboration to effectively and efficiently produce the interdisciplinary science that is needed to improve patient-centered outcomes. The authors propose the use of the Forging Alliances in Interdisciplinary Rehabilitation Research (FAIRR) logic model to provide guidance to rehabilitation scientists and clinicians who are committed to growing their involvement in interdisciplinary rehabilitation research. We describe the importance and key characteristics of the FAIRR model for conducting interdisciplinary rehabilitation research.

Welding and Joining of Titanium Aluminides

PubMed Central

Cao, Jian; Qi, Junlei; Song, Xiaoguo; Feng, Jicai

2014-01-01

Welding and joining of titanium aluminides is the key to making them more attractive in industrial fields. The purpose of this review is to provide a comprehensive overview of recent progress in welding and joining of titanium aluminides, as well as to introduce current research and application. The possible methods available for titanium aluminides involve brazing, diffusion bonding, fusion welding, friction welding and reactive joining. Of the numerous methods, solid-state diffusion bonding and vacuum brazing have been most heavily investigated for producing reliable joints. The current state of understanding and development of every welding and joining method for titanium aluminides is addressed respectively. The focus is on the fundamental understanding of microstructure characteristics and processing–microstructure–property relationships in the welding and joining of titanium aluminides to themselves and to other materials. PMID:28788113

Well 9-1 Logs and Data: Roosevelt Hot Spring Area, Utah (FORGE)

DOE Data Explorer

Joe Moore

2016-03-03

This is a compilation of logs and data from Well 9-1 in the Roosevelt Hot Springs area in Utah. This well is also in the Utah FORGE study area. The file is in a compressed .zip format and there is a data inventory table (Excel spreadsheet) in the root folder that is a guide to the data that is accessible in subfolders.

Rough titanium alloys regulate osteoblast production of angiogenic factors.

PubMed

Olivares-Navarrete, Rene; Hyzy, Sharon L; Gittens, Rolando A; Schneider, Jennifer M; Haithcock, David A; Ullrich, Peter F; Slosar, Paul J; Schwartz, Zvi; Boyan, Barbara D

2013-11-01

Polyether-ether-ketone (PEEK) and titanium-aluminum-vanadium (titanium alloy) are used frequently in lumbar spine interbody fusion. Osteoblasts cultured on microstructured titanium generate an environment characterized by increased angiogenic factors and factors that inhibit osteoclast activity mediated by integrin α2β1 signaling. It is not known if this is also true of osteoblasts on titanium alloy or PEEK. The purpose of this study was to determine if osteoblasts generate an environment that supports angiogenesis and reduces osteoclastic activity when grown on smooth titanium alloy, rough titanium alloy, or PEEK. This in vitro study compared angiogenic factor production and integrin gene expression of human osteoblast-like MG63 cells cultured on PEEK or titanium-aluminum-vanadium (titanium alloy). MG63 cells were grown on PEEK, smooth titanium alloy, or rough titanium alloy. Osteogenic microenvironment was characterized by secretion of osteoprotegerin and transforming growth factor beta-1 (TGF-β1), which inhibit osteoclast activity and angiogenic factors including vascular endothelial growth factor A (VEGF-A), fibroblast growth factor 2 (FGF-2), and angiopoietin-1 (ANG-1). Expression of integrins, transmembrane extracellular matrix recognition proteins, was measured by real-time polymerase chain reaction. Culture on titanium alloy stimulated osteoprotegerin, TGF-β1, VEGF-A, FGF-2, and angiopoietin-1 production, and levels were greater on rough titanium alloy than on smooth titanium alloy. All factors measured were significantly lower on PEEK than on smooth or rough titanium alloy. Culture on titanium alloy stimulated expression of messenger RNA for integrins that recognize Type I collagen in comparison with PEEK. Rough titanium alloy stimulated cells to create an osteogenic-angiogenic microenvironment. The osteogenic-angiogenic responses to titanium alloy were greater than PEEK and greater on rough titanium alloy than on smooth titanium alloy. Surface

The formation of titanium dioxide crystallite nanoparticles during activation of PAN nanofibers containing titanium isopropoxide

NASA Astrophysics Data System (ADS)

Mehrpouya, Fahimeh; Tavanai, Hossein; Morshed, Mohammad; Ghiaci, Mehran

2012-08-01

Activated carbon (AC) can act as an important carrier for TiO2 nanoparticles. TiO2 nanoparticle can be fabricated by the hydrolysis and condensation of titanium alkoxides like titanium isopropoxide. This study showed that the formation of titanium dioxide crystallite nanoparticle during activation of PAN nanofibers containing titanium isopropoxide leads to the formation of mainly anatase crystal TiO2 nanoparticle in AC nanofibers, with a good dispersion in both the longitude and cross section of nanofibers. The TiO2 crystallite size lies in the range of 7.3-11.3 nm. The dispersion of TiO2 nanoparticles in the matrix of AC nanofibers is far superior to the direct mixing of TiO2 nanoparticles in the original electrospinning solution.

Oxygen-Barrier Coating for Titanium

NASA Technical Reports Server (NTRS)

Clark, Ronald K.; Unnam, Jalaiah

1987-01-01

Oxygen-barrier coating for titanium developed to provide effective and low-cost means for protecting titanium alloys from oxygen in environment when alloys used in high-temperature mechanical or structural applications. Provides protective surface layer, which reduces extent of surface oxidation of alloy and forms barrier to diffusion of oxygen, limiting contamination of substrate alloy by oxygen. Consists of submicron layer of aluminum deposited on surface of titanium by electron-beam evaporation, with submicron layer of dioxide sputtered onto aluminum to form coat.

Primary cementless total hip arthroplasty with second-generation metal-on-metal bearings: a concise follow-up, at a minimum of seventeen years, of a previous report.

PubMed

Lass, R; Grübl, A; Kolb, A; Domayer, S; Csuk, C; Kubista, B; Giurea, A; Windhager, R

2014-03-05

Second-generation, metal-on-metal bearings were introduced in 1988, to reduce wear and avoid polyethylene particle-induced osteolysis from total hip arthroplasty. In 2007, we reported the long-term results of ninety-eight patients (105 hips) who underwent primary cementless total hip arthroplasty involving the use of a prosthesis with a high-carbide-concentration, metal-on-metal articulating surface between November 1992 and May 1994. The present study gives an update on this patient cohort. At a minimum of seventeen years postoperatively, forty-nine patients (fifty-two hips) were available for follow-up examination. We retrospectively evaluated clinical and radiographic results as well as serum metal concentration. The mean patient age at the time of the index arthroplasty was fifty-six years. Three cups (6% of the hips) and one stem (2% of the hips) were revised because of aseptic loosening of the implants combined with focal osteolysis. At the time of the latest follow-up evaluation, the mean Harris hip score was 88.8 points, and the mean University of California Los Angeles (UCLA) activity score was 6.7 points. The cumulative rate of implant survival, with aseptic failure as the end point, was 93.0% at 18.8 years. The median serum cobalt concentration in patients whose hip implant was the only source of cobalt was 0.70 μg/L (range, 0.4 to 5.1 μg/L), showing no increase in the value as noted at a minimum of ten years of follow-up. The clinical and radiographic results of our study, which, to our knowledge, represent the longest duration of follow-up for a series of cementless total hip arthroplasties with use of a 28-mm metal-on-metal bearing, continue to be comparable with the results observed for other hard-on-hard bearings.

The Ties That Bind: How Social Capital Is Forged and Forfeited in Teacher Communities

ERIC Educational Resources Information Center

Bridwell-Mitchell, E. N.; Cooc, North

2016-01-01

The effects of social capital on school improvement make it important to understand how teachers forge, maintain, or forfeit collegial relationships. Two common explanations focused on formal organizational features and individual characteristics do not address how social capital accrues from informal dynamics of teachers' interactions in…

Analysis of titanium content in titanium tetrachloride solution

NASA Astrophysics Data System (ADS)

Bi, Xiaoguo; Dong, Yingnan; Li, Shanshan; Guan, Duojiao; Wang, Jianyu; Tang, Meiling

2018-03-01

Strontium titanate, barium titan and lead titanate are new type of functional ceramic materials with good prospect, and titanium tetrachloride is a commonly in the production such products. Which excellent electrochemical performance of ferroelectric tempreature coefficient effect.In this article, three methods are used to calibrate the samples of titanium tetrachloride solution by back titration method, replacement titration method and gravimetric analysis method. The results show that the back titration method has many good points, for example, relatively simple operation, easy to judgment the titration end point, better accuracy and precision of analytical results, the relative standard deviation not less than 0.2%. So, it is the ideal of conventional analysis methods in the mass production.

Ultrasonic effects on titanium tanning of leather.

PubMed

Peng, Biyu; Shi, Bi; Sun, Danhong; Chen, Yaowen; Shelly, Dennis C

2007-03-01

The effects of ultrasound on titanium tanning of leather were investigated. Either 20 or 40 kHz ultrasound was applied to the titanium tanning of pigskins. Five different treatment conditions were carried out and the effects were examined, such as leather shrinkage temperature (T(s)), titanium content and titanium distribution in the leather. Overall heat loading was carefully controlled. Results showed that 20 kHz ultrasound effectively improves titanium agent penetration into the hide and increases the leather's shrinkage temperature. Doubling the frequency to 40 kHz produced negligible enhancements. An impressive 105.6 degrees C T(s) was achieved using 20 kHz ultrasound pretreatment of the tanning liquor followed by 20 kHz ultrasound in the tanning mixture (liquor plus pigskins) in a special salt-free medium. Finally, using a unique ultrasonic tanning drum with 26.5 kHz ultrasound, the T(s) reached a record level of 106.5 degrees C, a value not achieved in conventional (no ultrasound) titanium tanning. The ultrasonic effects on titanium tanning of leather are judged to make a superior mineral tanned leather.

An Assessment of the Ductile Fracture Behavior of Hot Isostatically Pressed and Forged 304L Stainless Steel

NASA Astrophysics Data System (ADS)

Cooper, A. J.; Smith, R. J.; Sherry, A. H.

2017-05-01

Type 300 austenitic stainless steel manufactured by hot isostatic pressing (HIP) has recently been shown to exhibit subtly different fracture behavior from that of equivalent graded forged steel, whereby the oxygen remaining in the component after HIP manifests itself in the austenite matrix as nonmetallic oxide inclusions. These inclusions facilitate fracture by acting as nucleation sites for the initiation, growth, and coalescence of microvoids in the plastically deforming austenite matrix. Here, we perform analyses based on the Rice-Tracey (RT) void growth model, supported by instrumented Charpy and J-integral fracture toughness testing at ambient temperature, to characterize the degree of void growth ahead of both a V-notch and crack in 304L stainless steel. We show that the hot isostatically pressed (HIP'd) 304L steel exhibits a lower critical void growth at the onset of fracture than that observed in forged 304L steel, which ultimately results in HIP'd steel exhibiting lower fracture toughness at initiation and impact toughness. Although the reduction in toughness of HIP'd steel is not detrimental to its use, due to the steel's sufficiently high toughness, the study does indicate that HIP'd and forged 304L steel behave as subtly different materials at a microstructural level with respect to their fracture behavior.

West Flank Coso, CA FORGE 3D geologic model

DOE Data Explorer

Doug Blankenship

2016-03-01

This is an x,y,z file of the West Flank FORGE 3D geologic model. Model created in Earthvision by Dynamic Graphic Inc. The model was constructed with a grid spacing of 100 m. Geologic surfaces were extrapolated from the input data using a minimum tension gridding algorithm. The data file is tabular data in a text file, with lithology data associated with X,Y,Z grid points. All the relevant information is in the file header (the spatial reference, the projection etc.) In addition all the fields in the data file are identified in the header.

Production of Titanium Metal by an Electrochemical Molten Salt Process

NASA Astrophysics Data System (ADS)

Fatollahi-Fard, Farzin

Titanium production is a long and complicated process. What we often consider to be the standard method of primary titanium production (the Kroll process), involves many complex steps both before and after to make a useful product from titanium ore. Thus new methods of titanium production, especially electrochemical processes, which can utilize less-processed feedstocks have the potential to be both cheaper and less energy intensive than current titanium production processes. This project is investigating the use of lower-grade titanium ores with the electrochemical MER process for making titanium via a molten salt process. The experimental work carried out has investigated making the MER process feedstock (titanium oxycarbide) with natural titanium ores--such as rutile and ilmenite--and new ways of using the MER electrochemical reactor to "upgrade" titanium ores or the titanium oxycarbide feedstock. It is feasible to use the existing MER electrochemical reactor to both purify the titanium oxycarbide feedstock and produce titanium metal.

REDUCING TITANIUM TETRACHLORIDE WITH HIGH-SURFACE SODIUM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fleck, D.C.; Wong, M.M.; Baker, D.H. Jr.

1960-01-01

A method of using sodium for reducing titanium tetrachloride, developed to improve the extractive metallurgy of titunium, is described. Finely divided titanium metal, titanium lower chlorides, or a mixture thereof was produced in a continuous operation at temperatures between 105 and 205 deg C by the reaction of molten sodium and vaporized titanium tetrachloride in an agitated bed of finely divided inert solids (powdered sodium chloride or the reaction products). Composition of the product was controlled by varying the relative quantities of sodium and titanium tetrachloride used. A description of the operations and analytical data of the reaction products aremore » given. (auth)« less

Research and Development on Titanium Alloys

DTIC Science & Technology

1949-10-31

EVALUATION OF EPERIMENTAL TITANIUM-BASE ALLOYS• 65 Binary Alloys of Titanium . . . . .. 65 Titanium-Silver Alloys. . . . . ..... ... 68 Mechanical Properties...using a technique in melting designed to give more uniform distribution of the alloying additions. NMATTWLL MOMORIAL INSTITUTE 4...tc Dr. Derge for analysis. BATTELLE MEMORIAL INSTITUTE -107- 2TABLE 28. OXYGEN STANDARDS FOR ANALYSIS Wt fSapl Pein Cen Designation Sample lielting, 1

Ultrafine-grained titanium for medical implants

DOEpatents

Zhu, Yuntian T.; Lowe, Terry C.; Valiev, Ruslan Z.; Stolyarov, Vladimir V.; Latysh, Vladimir V.; Raab, Georgy J.

2002-01-01

We disclose ultrafine-grained titanium. A coarse-grained titanium billet is subjected to multiple extrusions through a preheated equal channel angular extrusion (ECAE) die, with billet rotation between subsequent extrusions. The resulting billet is cold processed by cold rolling and/or cold extrusion, with optional annealing. The resulting ultrafine-grained titanium has greatly improved mechanical properties and is used to make medical implants.

Deducing material quality in cast and hot-forged steels by new bending test

NASA Astrophysics Data System (ADS)

Valberg, Henry; Langøy, Morten; Nedreberg, Mette; Helvig, Torgeir

2017-10-01

A special bend test has been developed and applied for the purpose of characterization and comparison of the material ductility in crankpin steel discs manufactured by casting, or casting subsequently followed by hot open-die forging (ODF) or closed-die forging (CDF). The bending test specimen consists of a small rectangular plate of material with a round hole cut out in the middle. The "eye-shape" specimens were cut out from various positions either near to the surface of, or from the interior of the discs. The test method revealed differences in ductility for the investigated materials, and for different depth positions inside the discs. The roughening of the specimen surface on the top-side of the specimen bend also varied dependent on the processing method for the material. Current results show that this test method is useful for evaluation of material quality in differently processed material. Experimental bend test results are presented for differently processed variants of the same material, i.e., crankpin discs either made by solely casting or casting subsequently followed by hot working either by ODF or CDF.

Assessment of densification and mechanical property of AISI 8630 steel composition on different heat treatments produced through hot upsetting powder preform forging

NASA Astrophysics Data System (ADS)

Bala, Y. G.; Sankaranarayanan, S. Raman; Pandey, K. S.

2015-11-01

The present investigation was carried out to evaluate the densification, mechanical properties, microstructural and fractrography effects of AISI 8630 steel composition developed through powder preform forging under different heat treated conditions. Sintered preforms of different aspect ratios such as 0.6, 0.9, and 1.2 were hot upset forged to disc shape to different height strain to analysis the densification mechanism. Certain relationships relating strains, Poisson's ratio relating densification have revealed the effect of preform geometry on densification kinetics and resulted in the polynomial expression with justified regression coefficient greater the 0.9 or unity. The preforms of aspect ratio of 1.1 were hot upset forged to square cross section bars and transferred to different quenching medium like oil, water, furnace and air to assess its mechanical properties. Comparing the temperament of the heat treatments, sintered forged homogenised water quenched sample upshot in the maximum Tensile strength with least per centage elongation andthe furnace cooled sample shows the maximum toughness with desirable per centage elongation and least tensile strength. Microstructure stated the presence of varying ferrite and pearlite distribution and fractograph studies has disclosed the mixed mode of failure on the effect of varying heat treatments progression has affected the properties significantly.

Titanium: Industrial Base, Price Trends, and Technology Initiatives

DTIC Science & Technology

2009-01-01

respectively.3 All titanium metal production begins with rutile (titanium oxide, or TiO2). High-titania slag , produced by ilmen- ite smelting, is the first...Ilmenite ores are used in iron production. They leave a TiO2-rich slag , which is usually upgraded to be used in titanium production. 4 According to the...and least expensive process for producing titanium sponge, has four major steps. First, rutile con- centrate or synthetic rutile (titanium slag ) is

A new method for production of titanium vapor and synthesis of titanium nitride coatings

NASA Astrophysics Data System (ADS)

Grigoriev, Sergey N.; Melnik, Yury A.; Metel, Alexander S.; Volosova, Marina A.

2018-03-01

It is proposed to synthesize on machine parts and cutting tools wear-resistant titanium nitride coatings with the help of the hollow-cathode glow discharge, a molybdenum crucible for titanium evaporation being used as the anode of the discharge and a process vacuum chamber being used as the hollow cathode. The research revealed that at the anode surface area less than a critical value S* = (2m/M)1/2S, where S is the area of the chamber walls, m is the mass of electrons and M is the mass of ions, the anode fall of potential is positive and grows from ˜50 V at argon pressure p = 0.2 Pa to ˜2 kV at p = 0.02 Pa. At the discharge current I = 0.6 A electrons accelerated by the anode fall of 0.9 kV transport into the crucible with the inner diameter of 12 mm the power of ˜0.54 kW, which allows the titanium evaporation and the coating deposition rate of 5 µm·h-1 on a substrate distanced from the crucible at 100 mm. After the argon is replaced with the nitrogen, titanium nitride coating without titanium droplets is synthesized the deposition rate amounting to about the same value.

Assessment of nickel titanium and beta titanium corrosion resistance behavior in fluoride and chloride environments.

PubMed

Kassab, Elisa J; Gomes, José Ponciano

2013-09-01

To assess the influence of fluoride concentration on the corrosion behavior of nickel titanium (NiTi) superelastic wire and to compare the corrosion resistance of NiTi with that of beta titanium alloy in physiological solution with and without addition of fluoride. NiTi corrosion resistance was investigated through electrochemical impedance spectroscopy and anodic polarization in sodium chloride (NaCl 0.15 M) with and without addition of 0.02 M sodium fluoride (NaF), and the results were compared with those associated with beta titanium. The influence of fluoride concentration on NiTi corrosion behavior was assessed in NaCl (0.15 M) with and without 0.02, 0.04, 0.05, 0.07, and 0.12 M NaF solution. Galvanic corrosion between NiTi and beta titanium were investigated. All samples were characterized by scanning electron microscopy. Polarization resistance decreased when NaF concentration was increased, and, depending on NaF concentration, NiTi can suffer localized or generalized corrosion. In NaCl solution with 0.02 M NaF, NiTi suffer localized corrosion, while beta titanium alloys remained passive. Current values near zero were observed by galvanic coupling of NiTi and beta titanium. There is a decrease in NiTi corrosion resistance in the presence of fluoride. The corrosion behavior of NiTi alloy depends on fluoride concentration. When 0.02 and 0.04 M of NaF were added to the NaCl solution, NiTi presented localized corrosion. When NaF concentration increased to 0.05, 0.07, and 0.12 M, the alloy presented general corrosion. NiTi corrosion resistance behavior is lower than that of beta titanium. Galvanic coupling of these alloys does not increase corrosion rates.

The Growth Behavior of Titanium Boride Layers in α and β Phase Fields of Titanium

NASA Astrophysics Data System (ADS)

Lv, Xiaojun; Hu, Lingyun; Shuang, Yajing; Liu, Jianhua; Lai, Yanqing; Jiang, Liangxing; Li, Jie

2016-07-01

In this study, the commercially pure titanium was successfully electrochemical borided in a borax-based electrolyte. The process was carried out at a constant cathodic current density of 300 mA cm-2 and at temperatures of 1123 K and 1223 K (850 °C and 950 °C) for 0.5, 1, 2, 3, and 5 hours. The growth behavior of titanium boride layers in the α phase field of titanium was compared with that in the β phase field. After boriding, the presence of both the TiB2 top layer and TiB whisker sub-layer was confirmed by the X-ray diffraction (XRD) and scanning electron microscope. The relationship between the thickness of boride layers and boriding time was found to have a parabolic character in both α and β phase fields of titanium. The TiB whiskers showed ultra-fast growth rate in the β phase field. Its growth rate constant was found to be as high as 3.2002 × 10-13 m2 s-1. Besides, the chemical resistance of the TiB2 layer on the surface of titanium substrate was characterized by immersion tests in molten aluminum.

Sonochemical method for producing titanium metal powder.

PubMed

Halalay, Ion C; Balogh, Michael P

2008-07-01

We demonstrate a sonochemical method for producing titanium metal powder. The method uses low intensity ultrasound in a hydrocarbon solvent at near-ambient temperatures to first create a colloidal suspension of liquid sodium-potassium alloy in the solvent and then to reduce liquid titanium tetrachloride to titanium metal under cavitation conditions. XRD data collected for the reaction products after the solvent removal show only NaCl and KCl, with no diffraction peaks attributable to titanium metal or other titanium compounds, indicating either the formation of amorphous metal or extremely small crystallite size. TEM micrographs show that hollow spheres formed of halide salts and titanium metal, with diameters with diameters ranging from 100 to 500 nm and a shell thickness of 20 to 40 nm form during the synthesis, suggesting that the sonochemical reaction occurs inside the liquid shell surrounding the cavitation bubbles. Metal particle sizes are estimated to be significantly smaller than 40 nm from TEM data. XRD data of the powder after annealing and prior to removal of the alkali chloride salts provides direct evidence that titanium metal was formed during the sonochemical synthesis.

Formation of titanium diboride coatings during the anodic polarization of titanium in a chloride melt with a low boron oxide content

NASA Astrophysics Data System (ADS)

Elshina, L. A.; Malkov, V. B.; Molchanova, N. G.

2015-02-01

The corrosion-electrochemical behavior of titanium in a molten eutectic mixture of cesium and sodium chlorides containing up to 1 wt % boron oxide is studied in the temperature range 810-870 K in an argon atmosphere. The potential, the current, and the rate of titanium corrosion are determined. The optimum conditions of forming a dense continuous titanium diboride coating on titanium with high adhesion to the metallic base are found for the anodic activation of titanium in the molten electrolyte under study.

Titanium Ions Release from an Innovative Titanium-Magnesium Composite: an in Vitro Study.

PubMed

Stanec, Zlatko; Halambek, Jasna; Maldini, Krešimir; Balog, Martin; Križik, Peter; Schauperl, Zdravko; Ćatić, Amir

2016-03-01

The innovative titanium-magnesium composite (Ti-Mg) was produced by powder metallurgy (P/M) method and is characterized in terms of corrosion behavior. Two groups of experimental material, 1 mass% (Ti-1Mg) and 2 mass% (Ti-2Mg) of magnesium in titanium matrix, were tested and compared to commercially pure titanium (CP Ti). Immersion test and chemical analysis of four solutions: artificial saliva; artificial saliva pH 4; artificial saliva with fluoride and Hank balanced salt solution were performed after 42 days of immersion, using inductively coupled plasma mass spectrometry (ICP-MS) to detect the amount of released titanium ions (Ti). SEM and EDS analysis were used for surface characterization. The difference between the results from different test solutions was assessed by ANOVA and Newman-Keuls test at p<0.05. The influence of predictor variables was found by multiple regression analysis. The results of the present study revealed a low corrosion rate of titanium from the experimental Ti-Mg group. Up to 46 and 23 times lower dissolution of Ti from Ti-1Mg and Ti-2Mg, respectively was observed compared to the control group. Among the tested solutions, artificial saliva with fluorides exhibited the highest corrosion effect on all specimens tested. SEM micrographs showed preserved dual phase surface structure and EDS analysis suggested a favorable surface bioactivity. In conclusion, Ti-Mg produced by P/M as a material with better corrosion properties when compared to CP Ti is suggested.

Yttria Nanoparticle Reinforced Commercially Pure (CP) Titanium

DTIC Science & Technology

2011-09-01

nanoparticles as well as titanium boride (TiB) reinforcements were produced through gas atomization. After consolidation and extrusion, room temperature...pure FE iron O oxygen Ti titanium TiB titanium boride TYS tensile yield strength UTS ultimate tensile strength wt% weight percent Y2O3

Hydrocarbon Deposition Attenuates Osteoblast Activity on Titanium

PubMed Central

Hayashi, R.; Ueno, T.; Migita, S.; Tsutsumi, Y.; Doi, H.; Ogawa, T.; Hanawa, T.; Wakabayashi, N.

2014-01-01

Although the reported percentage of bone-implant contact is far lower than 100%, the cause of such low levels of bone formation has rarely been investigated. This study tested the negative biological effect of hydrocarbon deposition onto titanium surfaces, which has been reported to be inevitable. Osteogenic MC3T3-E1 cells were cultured on titanium disks on which the carbon concentration was experimentally regulated to achieve carbon/titanium (C/Ti) ratios of 0.3, 0.7, and 1.0. Initial cellular activities such as cell attachment and cell spreading were concentration-dependently suppressed by the amount of carbon on the titanium surface. The osteoblastic functions of alkaline phosphatase activity and calcium mineralization were also reduced by more than 40% on the C/Ti (1.0) surface. These results indicate that osteoblast activity is influenced by the degree of hydrocarbon contamination on titanium implants and suggest that hydrocarbon decomposition before implant placement may increase the biocompatibility of titanium. PMID:24868012

Simulations and Experiments of Hot Forging Design and Evaluation of the Aircraft Landing Gear Barrel Al Alloy Structure

NASA Astrophysics Data System (ADS)

Ram Prabhu, T.

2016-04-01

In the present study, the hot forging design of a typical landing gear barrel was evolved using finite element simulations and validated with experiments. A DEFORM3D software was used to evolve the forging steps to obtain the sound quality part free of defects with minimum press force requirements. The hot forging trial of a barrel structure was carried out in a 30 MN hydraulic press based on the simulation outputs. The tensile properties of the part were evaluated by taking samples from all three orientations (longitudinal, long transverse, short transverse). The hardness and microstructure of the part were also investigated. To study the soundness of the product, fluorescent penetrant inspection and ultrasonic testing were performed in order to identify any potential surface or internal defects in the part. From experiments, it was found that the part was formed successfully without any forging defects such as under filling, laps, or folds that validated the effectiveness of the process simulation. The tensile properties of the part were well above the specification limit (>10%) and the properties variation with respect to the orientation was less than 2.5%. The part has qualified the surface defects level of Mil Std 1907 Grade C and the internal defects level of AMS 2630 Class A (2 mm FBh). The microstructure shows mean grain length and width of 167 and 66 µm in the longitudinal direction. However, microstructure results revealed that the coarse grain structure was observed on the flat surface near the lug region due to the dead zone formation. An innovative and simple method of milling the surface layer after each pressing operation was applied to solve the problem of the surface coarse grain structure.

UV photofunctionalization promotes nano-biomimetic apatite deposition on titanium

PubMed Central

Saita, Makiko; Ikeda, Takayuki; Yamada, Masahiro; Kimoto, Katsuhiko; Lee, Masaichi Chang-Il; Ogawa, Takahiro

2016-01-01

Background Although biomimetic apatite coating is a promising way to provide titanium with osteoconductivity, the efficiency and quality of deposition is often poor. Most titanium implants have microscale surface morphology, and an addition of nanoscale features while preserving the micromorphology may provide further biological benefit. Here, we examined the effect of ultraviolet (UV) light treatment of titanium, or photofunctionalization, on the efficacy of biomimetic apatite deposition on titanium and its biological capability. Methods and results Micro-roughed titanium disks were prepared by acid-etching with sulfuric acid. Micro-roughened disks with or without photofunctionalization (20-minute exposure to UV light) were immersed in simulated body fluid (SBF) for 1 or 5 days. Photofunctionalized titanium disks were superhydrophilic and did not form surface air bubbles when immersed in SBF, whereas non-photofunctionalized disks were hydrophobic and largely covered with air bubbles during immersion. An apatite-related signal was observed by X-ray diffraction on photofunctionalized titanium after 1 day of SBF immersion, which was equivalent to the one observed after 5 days of immersion of control titanium. Scanning electron microscopy revealed nodular apatite deposition in the valleys and at the inclines of micro-roughened structures without affecting the existing micro-configuration. Micro-roughened titanium and apatite-deposited titanium surfaces had similar roughness values. The attachment, spreading, settling, proliferation, and alkaline phosphate activity of bone marrow-derived osteoblasts were promoted on apatite-coated titanium with photofunctionalization. Conclusion UV-photofunctionalization of titanium enabled faster deposition of nanoscale biomimetic apatite, resulting in the improved biological capability compared to the similarly prepared apatite-deposited titanium without photofunctionalization. Photofunctionalization-assisted biomimetic apatite

40 CFR 721.10553 - Potassium titanium oxide.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Potassium titanium oxide. 721.10553... Substances § 721.10553 Potassium titanium oxide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as potassium titanium oxide (PMN P-06-149; CAS No. 12673-69...

40 CFR 721.10553 - Potassium titanium oxide.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Potassium titanium oxide. 721.10553... Substances § 721.10553 Potassium titanium oxide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as potassium titanium oxide (PMN P-06-149; CAS No. 12673-69...

Rapid prototyped porous nickel–titanium scaffolds as bone substitutes

PubMed Central

Hoffmann, Waldemar; Bormann, Therese; Rossi, Antonella; Müller, Bert; Schumacher, Ralf; Martin, Ivan; Wendt, David

2014-01-01

While calcium phosphate–based ceramics are currently the most widely used materials in bone repair, they generally lack tensile strength for initial load bearing. Bulk titanium is the gold standard of metallic implant materials, but does not match the mechanical properties of the surrounding bone, potentially leading to problems of fixation and bone resorption. As an alternative, nickel–titanium alloys possess a unique combination of mechanical properties including a relatively low elastic modulus, pseudoelasticity, and high damping capacity, matching the properties of bone better than any other metallic material. With the ultimate goal of fabricating porous implants for spinal, orthopedic and dental applications, nickel–titanium substrates were fabricated by means of selective laser melting. The response of human mesenchymal stromal cells to the nickel–titanium substrates was compared to mesenchymal stromal cells cultured on clinically used titanium. Selective laser melted titanium as well as surface-treated nickel–titanium and titanium served as controls. Mesenchymal stromal cells had similar proliferation rates when cultured on selective laser melted nickel–titanium, clinically used titanium, or controls. Osteogenic differentiation was similar for mesenchymal stromal cells cultured on the selected materials, as indicated by similar gene expression levels of bone sialoprotein and osteocalcin. Mesenchymal stromal cells seeded and cultured on porous three-dimensional selective laser melted nickel–titanium scaffolds homogeneously colonized the scaffold, and following osteogenic induction, filled the scaffold’s pore volume with extracellular matrix. The combination of bone-related mechanical properties of selective laser melted nickel–titanium with its cytocompatibility and support of osteogenic differentiation of mesenchymal stromal cells highlights its potential as a superior bone substitute as compared to clinically used titanium. PMID:25383165

Well 14-2 Logs and Data: Roosevelt Hot Spring Area, Utah (Utah FORGE)

DOE Data Explorer

Joe Moore

2016-03-03

This is a compilation of logs and data from Well 14-2 in the Roosevelt Hot Springs area in Utah. This well is also in the Utah FORGE study area. The file is in a compressed .zip format and there is a data inventory table (Excel spreadsheet) in the root folder that is a guide to the data that is accessible in subfolders.

Well 52-21 Logs and Data: Roosevelt Hot Spring Area, Utah (Utah FORGE)

DOE Data Explorer

Joe Moore

2016-03-03

This is a compilation of logs and data from Well 52-21 in the Roosevelt Hot Springs area in Utah. This well is also in the Utah FORGE study area. The file is in a compressed .zip format and there is a data inventory table (Excel spreadsheet) in the root folder that is a guide to the data that is accessible in subfolders.

Well 82-33 Logs and Data: Roosevelt Hot Spring Area, Utah (Utah FORGE)

DOE Data Explorer

Joe Moore

2016-03-03

This is a compilation of logs and data from Well 82-33 in the Roosevelt Hot Springs area in Utah. This well is also in the Utah FORGE study area. The file is in a compressed .zip format and there is a data inventory table (Excel spreadsheet) in the root folder that is a guide to the data that is accessible in subfolders.

Snake River Plain FORGE Well Data for USGS-142

DOE Data Explorer

Robert Podgorney

2015-11-23

Well data for the USGS-142 well located in eastern Snake River Plain, Idaho. This data collection includes lithology reports, borehole logs, and photos of rhyolite core samples. This collection of data has been assembled as part of the site characterization data used to develop the conceptual geologic model for the Snake River Plain site in Idaho, as part of phase 1 of the Frontier Observatory for Research in Geothermal Energy (FORGE) initiative. They were assembled by the Snake River Geothermal Consortium (SRGC), a team of collaborators that includes members from national laboratories, universities, industry, and federal agencies, lead by the Idaho National Laboratory (INL).

Titanium alkoxide compound

DOEpatents

Boyle, Timothy J [Albuquerque, NM

2007-08-14

A titanium alkoxide composition is provided, as represented by the chemical formula (OC.sub.6H.sub.5N).sub.2Ti(OC.sub.6H.sub.5NH.sub.2).sub.2. As prepared, the compound is a crystalline substance with a hexavalent titanium atom bonded to two OC.sub.6H.sub.5NH.sub.2 groups and two OC.sub.6H.sub.5N groups with a theoretical molecular weight of 480.38, comprising 60.01% C, 5.04% H and 11.66% N.

Self-adaptive multimethod optimization applied to a tailored heating forging process

NASA Astrophysics Data System (ADS)

Baldan, M.; Steinberg, T.; Baake, E.

2018-05-01

The presented paper describes an innovative self-adaptive multi-objective optimization code. Investigation goals concern proving the superiority of this code compared to NGSA-II and applying it to an inductor’s design case study addressed to a “tailored” heating forging application. The choice of the frequency and the heating time are followed by the determination of the turns number and their positions. Finally, a straightforward optimization is performed in order to minimize energy consumption using “optimal control”.

Titanium Ions Release from an Innovative Titanium-Magnesium Composite: an in Vitro Study

PubMed Central

Halambek, Jasna; Maldini, Krešimir; Balog, Martin; Križik, Peter; Schauperl, Zdravko; Ćatić, Amir

2016-01-01

Background The innovative titanium-magnesium composite (Ti-Mg) was produced by powder metallurgy (P/M) method and is characterized in terms of corrosion behavior. Material and methods Two groups of experimental material, 1 mass% (Ti-1Mg) and 2 mass% (Ti-2Mg) of magnesium in titanium matrix, were tested and compared to commercially pure titanium (CP Ti). Immersion test and chemical analysis of four solutions: artificial saliva; artificial saliva pH 4; artificial saliva with fluoride and Hank balanced salt solution were performed after 42 days of immersion, using inductively coupled plasma mass spectrometry (ICP-MS) to detect the amount of released titanium ions (Ti). SEM and EDS analysis were used for surface characterization. Results The difference between the results from different test solutions was assessed by ANOVA and Newman-Keuls test at p<0.05. The influence of predictor variables was found by multiple regression analysis. The results of the present study revealed a low corrosion rate of titanium from the experimental Ti-Mg group. Up to 46 and 23 times lower dissolution of Ti from Ti-1Mg and Ti-2Mg, respectively was observed compared to the control group. Among the tested solutions, artificial saliva with fluorides exhibited the highest corrosion effect on all specimens tested. SEM micrographs showed preserved dual phase surface structure and EDS analysis suggested a favorable surface bioactivity. Conclusion In conclusion, Ti-Mg produced by P/M as a material with better corrosion properties when compared to CP Ti is suggested. PMID:27688425

Attachment of Porphyromonas gingivalis to corroded commercially pure titanium and titanium-aluminum-vanadium alloy.

PubMed

Barão, Valentim A R; Yoon, Cheon Joo; Mathew, Mathew T; Yuan, Judy Chia-Chun; Wu, Christine D; Sukotjo, Cortino

2014-09-01

Titanium dental material can become corroded because of electrochemical interaction in the oral environment. The corrosion process may result in surface modification. It was hypothesized that a titanium surface modified by corrosion may enhance the attachment of periodontal pathogens. This study evaluates the effects of corroded titanium surfaces on the attachment of Porphyromonas gingivalis. Commercially pure titanium (cp-Ti) and titanium-aluminum-vanadium alloy (Ti-6Al-4V) disks were used. Disks were anodically polarized in a standard three-electrode setting in a simulated oral environment with artificial saliva at pH levels of 3.0, 6.5, or 9.0. Non-corroded disks were used as controls. Surface roughness was measured before and after corrosion. Disks were inoculated with P. gingivalis and incubated anaerobically at 37°C. After 6 hours, the disks with attached P. gingivalis were stained with crystal violet, and attachment was expressed based on dye absorption at optical density of 550 nm. All assays were performed independently three times in triplicate. Data were analyzed by two-way analysis of variance, the Tukey honestly significant difference test, t test, and Pearson's correlation test (α = 0.05). Both cp-Ti and Ti-6Al-4V alloy-corroded disks promoted significantly more bacterial attachment (11.02% and 41.78%, respectively; P <0.0001) than did the non-corroded controls. Significantly more (11.8%) P. gingivalis attached to the cp-Ti disks than to the Ti-6Al-4V alloy disks (P <0.05). No significant difference in P. gingivalis attachment was noted among the corroded groups for both cp-Ti and Ti-6Al-4V alloy (P >0.05). There was no significant correlation between surface roughness and P. gingivalis attachment. A higher degree of corrosion on the titanium surface may promote increased bacterial attachment by oral pathogens.

Corrosion and Passivity Studies with Titanium

DTIC Science & Technology

1955-09-30

the (00.1) Face of a Titanium Single Crystal . - Part 3 Secondary Electron Emission from the Titanium Crystal , and from the Copper-Covered Titanium...ner upon the (00.1) face of a titaniuT single crystal . Low- energy electron diffraction is used to investigate the struc- ture of the deposit. Before...cathode emisaion is strongly dependent on the work function k. 8ince varies with crystal faces and the tip is generally so small that it is a single

SURFACE HARDENING OF TITANIUM BY TREATMENT IN MOLTEN BORAX

DOE Office of Scientific and Technical Information (OSTI.GOV)

Minkevich, A.N.; Shul'ga, Yu.N.

1957-01-01

The surface hardening of titanium and titanium alloys by treatment in molten borax was investigated. Commercial titanium, a titanium-tungsten alloy, and an aluminum-chromium-titanium alloy were used for the experiments. To prevent oxidation of the titanium and to protect the surface, electro-chemical protection was applied, the current density being 0.1 amp/cm/sup 2/ and the the specimens were coated with a thin layer of borax. The results showed that treatment in molten borax is an effective method of increasing surface hardness. However, the strength, mmalleabiltiy, and toughness of the hardness increase is discussed. (J.S.R.)

In situ formation of titanium carbide using titanium and carbon-nanotube powders by laser cladding

NASA Astrophysics Data System (ADS)

Savalani, M. M.; Ng, C. C.; Li, Q. H.; Man, H. C.

2012-01-01

Titanium metal matrix composite coatings are considered to be important candidates for high wear resistance applications. In this study, TiC reinforced Ti matrix composite layers were fabricated by laser cladding with 5, 10, 15 and 20 wt% carbon-nanotube. The effects of the carbon-nanotube content on phase composition, microstructure, micro-hardness and dry sliding wear resistance of the coating were studied. Microstructural observation using scanning electron microscopy showed that the coatings consisted of a matrix of alpha-titanium phases and the reinforcement phase of titanium carbide in the form of fine dendrites, indicating that titanium carbide was synthesized by the in situ reaction during laser irradiation. Additionally, measurements on the micro-hardness and dry sliding wear resistance of the coatings indicated that the mechanical properties were affected by the amount of carbon-nanotube in the starting precursor materials and were enhanced by increasing the carbon-nanotube content. Results indicated that the composite layers exhibit high hardness and excellent wear resistance.

Titanium diboride-chromium diboride-yttrium titanium oxide ceramic composition and a process for making the same

DOEpatents

Holcombe, Cressie E.; Dykes, Norman L.

1991-01-01

A ceramic composition is described. The ceramic composition consists essentially of from about 84 to 96 w/o titanium diboride, from about 1 to 9 w/o chromium diboride, and from about 3 to about 15 w/o yttrium-titanium-oxide. A method of making the ceramic composition is also described. The method of making the ceramic composition comprises the following steps: Step 1--A consolidated body containing stoichiometric quantities of titanium diboride and chromium diboride is provided. Step 2--The consolidated body is enclosed in and in contact with a thermally insulated package of yttria granules having a thickness of at least 0.5 inches. Step 3--The consolidated body enclosed in the thermally insulated package of yttria granules is heated in a microwave oven with microwave energy to a temperature equal to or greater than 1,900 degrees centigrade to sinter and uniformly disperse yttria particles having a size range from about 1 to about 12 microns throughout the consolidated body forming a densified body consisting essentially of titanium diboride, chromium diboride, and yttrium-titanium-oxide. The resulting densified body has enhanced fracture toughness and hardness.

Dynamic Multi-Axial Loading Response and Constitutive/Damage Modeling of Titanium and Titanium Alloys

DTIC Science & Technology

2006-06-24

crystals and assume same yield stress in tension and compression. Some anisotropic models have been proposed and used in the literature for HCP poly...2006), etc. These criteria dealt with the modeling of cubic crystals and assume same yield stress in tension an compression. Some anisotropic...Constitutive/Damage Modeling of Titanium and Titanium Alloys Principal Investigator: Akhtar S. Khan

Comparison of titanium cable tension band and nickel-titanium patella concentrator for patella fractures.

PubMed

Zhao, Quan-Ming; Gu, Xiao-Feng; Cheng, Li; Feng, De-Hong

2017-07-01

Patellar fractures account for approximately 1% of all fractures. Due to the patella's importance as regards the extensor mechanism, effort should be made to preserve the patella. Several operative treatment methods have been introduced for patella fractures. This study aims to compare the clinical effect of a titanium cable tension band and nickeltitanium (NiTi) patella concentrator (NT-PC) in treating patella fractures. Thirty-nine patients with patella fractures were enrolled in this retrospective study. All the patients were treated via the open reduction internal fixation procedure using a titanium cable tension band or NT-PC. All the patients were followed up over an average period of 13 months. The main outcome measures were operation time, time of fracture union, postoperative complications, and Böstman knee scores. Statistical analyses were conducted between the 2 groups. All the patients were operated on successfully. The operation time of the NT-PC treatment group was less than that of the titanium cable tension band treatment group (p < 0.05). The mean scores at the final follow-up were 28.2 and 27.6 points in the titanium cable tension band and NT-PC groups, respectively. No significant difference was observed between the excellent and good results (p > 0.05). Both titanium cable tension band and NT-PC showed good efficacy for the treatment of patellar fractures. NT-PC fixation, a new option for the treatment of patella fractures, is a simple and effective fixation method.

Direct dynamic synthesis of nanodispersed phases of titanium oxides upon sputtering of electrodischarge titanium plasma into an air atmosphere

NASA Astrophysics Data System (ADS)

Sivkov, A. A.; Gerasimov, D. Yu.; Nikitin, D. S.

2017-01-01

Experimental investigations of the possibility of directly synthesizing nanodispersed crystalline phases of titanium dioxides with rutile and anatase structures in a hypervelocity jet of electroerosion plasma generated by a coaxial magnetoplasma accelerator with titanium electrodes are presented. A powder product containing nanosized polymorphic phases of titanium dioxide with a spherical shape of particles has been manufactured.

Stress corrosion cracking of titanium alloys

NASA Technical Reports Server (NTRS)

May, R. C.; Beck, F. H.; Fontana, M. G.

1971-01-01

Experiments were conducted to study (1) the basic electrochemical behavior of titanium in acid chloride solutions and (2) the response of the metal to dynamic straining in the same evironment. The aim of this group of experiments was to simulate, as nearly as possible, the actual conditions which exist at the tip of a crack. One of the foremost theories proposed to explain the propagation of stress corrosion cracks is a hydrogen embrittlement theory involving the precipitation of embrittling titanium hydrides inside the metal near the crack tip. An initial survey of the basic electrochemical literature indicated that surface hydrides play a critical role in the electrochemistry of titanium in acid solutions. A comprehensive analysis of the effect of surface films, particularly hydrides, on the electrochemical behavior of titanium in these solution is presented.

76 FR 30200 - Forging Machines; Extension of the Office of Management and Budget's (OMB) Approval of...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-24

...: 187,264. Estimated Cost (Operation and Maintenance): $0. IV. Public Participation--Submission of... ensures that information is in the desired format, reporting burden (time and costs) is minimal... operated valves and switches. Inspection of Forging Machines, Guards, and Point-of-Operation Protection...

Evaluation of silicon carbide fiber/titanium composites

NASA Technical Reports Server (NTRS)

Jech, R. W.; Signorelli, R. A.

1979-01-01

Izod impact, tensile, and modulus of elasticity were determined for silicon carbide fiber/titanium composites to evaluate their potential usefulness as substitutes for titanium alloys or stainless steel in stiffness critical applications for aircraft turbine engines. Variations in processing conditions and matrix ductility were examined to produce composites having good impact strength in both the as-fabricated condition and after air exposure at elevated temperature. The impact strengths of composites containing 36 volume percent silicon carbide (SiC) fiber in an unalloyed (A-40) titanium matrix were found to be equal to unreinforced titanium-6 aluminum-4 vanadium alloy; the tensile strengths of the composites were marginally better than the unreinforced unalloyed (A-70) matrix at elevated temperature, though not at room temperature. At room temperature the modulus of elasticity of the composites was 48 percent higher than titanium or its alloys and 40 percent higher than that of stainless steel.

Microwave assisted scalable synthesis of titanium ferrite nanomaterials

NASA Astrophysics Data System (ADS)

Shukla, Abhishek; Bhardwaj, Abhishek K.; Singh, S. C.; Uttam, K. N.; Gautam, Nisha; Himanshu, A. K.; Shah, Jyoti; Kotnala, R. K.; Gopal, R.

2018-04-01

Titanium ferrite magnetic nanomaterials are synthesized by one-step, one pot, and scalable method assisted by microwave radiation. Effects of titanium content and microwave exposure time on size, shape, morphology, yield, bonding nature, crystalline structure, and magnetic properties of titanium ferrite nanomaterials are studied. As-synthesized nanomaterials are characterized by X-ray diffraction (XRD), ultraviolet-visible absorption spectroscopy (UV-Vis), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), Raman spectroscopy, transmission electron microscopy (TEM), and vibrating sample magnetometer measurements. XRD measurements depict the presence of two phases of titanium ferrite into the same sample, where crystallite size increases from ˜33 nm to 37 nm with the increase in titanium concentration. UV-Vis measurement showed broad spectrum in the spectral range of 250-600 nm which reveals that its characteristic peaks lie between ultraviolet and visible region; ATR-FTIR and Raman measurements predict iron-titanium oxide structures that are consistent with XRD results. The micrographs of TEM and selected area electron diffraction patterns show formation of hexagonal shaped particles with a high degree of crystallinity and presence of multi-phase. Energy dispersive spectroscopy measurements confirm that Ti:Fe compositional mass ratio can be controlled by tuning synthesis conditions. Increase of Ti defects into titanium ferrite lattice, either by increasing titanium precursor or by increasing exposure time, enhances its magnetic properties.

Snake River Plain FORGE Well Data for WO-2

DOE Data Explorer

Robert Podgorney

1991-07-29

Well data for the WO-2 well located in eastern Snake River Plain, Idaho. This data collection includes lithology reports, borehole logs, temperature at depth data, neutron density and gamma data, and rock strength parameters for the WO-2 well. This collection of data has been assembled as part of the site characterization data used to develop the conceptual geologic model for the Snake River Plain site in Idaho, as part of phase 1 of the Frontier Observatory for Research in Geothermal Energy (FORGE) initiative. They were assembled by the Snake River Geothermal Consortium (SRGC), a team of collaborators that includes members from national laboratories, universities, industry, and federal agencies, lead by the Idaho National Laboratory (INL).

[The bonding characteristic of titanium and RG experiment porcelain].

PubMed

Ren, Wei-hong; Guo, Tian-wen; Tian, Jie-mo; Zhang, Yun-long

2003-07-01

To study the bonding characteristic of Titanium and RG experiment porcelain. 5 specimens with a size of 10 mm x 5 mm x 1.4 mm were cast from pure titanium. Then 1 mm of RG experiment opaque and body porcelain were fused on the surface of the titanium specimens. The interface of titanium and porcelain was analyzed with a scanning electron microscope with energy-despersive spectrometry; 6 metal specimens with the size of 25 mm x 3 mm x 0.5 mm were cast from Ni-Cr alloy and a uniform thickness of 1 mm of VMK 99 porcelain was veneered on the central area of 8 mm x 3 mm 18 metal specimens as the same size were cast from pure titanium. The uniform thickness of 1 mm of VITA TITANKERAMIK porcelain, of Noritake super porcelain Ti-22 and of RG experiment porcelain were veneered on every 6 specimens respectively in the central area of 8 mm x 3 mm. The specimens were subjected to a three-point bending test on a load-test machine with a span of 20 mm, then the failure loads were recorded and statistically analysised. The RG porcelain/titanium crown was fabricated by fusing RG opaque porcelain and body porcelain to cast titanium substrate crown. The SEM results show no porosity and crackle were found in the interface. The energy-dispersive spectrometry show that there are Si, Ti and O in the 1 micro m layer between porcelain and titanium, which suggesting titanium and experiment porcelain bonding well. The three point test showed the fracture force for the combinations of titanium/VITA TITANKERAMIK porcelain, titanium/Noritake super porcelain Ti-22 and titanium/RG experiment porcelain were (7.233 +/- 2.539) N, (5.533 +/- 1.199) N and (6.316 +/- 1.433) N respectively. There were not statistically significant differences among them (t test, P < 0.01). The fracture force for the Ni-Cr alloy/VMK99 porcelain combination (12.733 +/- 3.297) N was significantly greater than those of the cast titanium/porcelain (t test, P > 0.05). The crown was translucent with no crack. RG porcelain is

Titanium-Oxygen Reactivity Study

NASA Technical Reports Server (NTRS)

Chafey, J. E.; Scheck, W. G.; Witzell, W. E.

1962-01-01

A program has been conducted at Astronautics to investigate the likelihood of occurrence of the catastrophic oxidation of titanium alloy sheet under conditions which simulate certain cases of accidental failure of the metal while it is in contact with liquid or gaseous oxygen. Three methods of fracturing the metal were used; they consisted of mechanical puncture, tensile fracture of welded joints, and perforation by very high velocity particles. The results of the tests which have been conducted provide further evidence of the reactivity of titanium with liquid and gaseous oxygen. The evidence indicates that the rapid fracturing of titanium sheet while it is in contact with oxygen initiates the catastrophic oxidation reaction. Initiation occurred when the speed of the fracture was some few feet per second, as in both the drop-weight puncture tests and the static tensile fracture tests of welded joints, as well as when the speed was several thousand feet per second, as in the simulated micrometeoroid penetration tests. The slow propagation of a crack, however, did not initiate the reaction. It may logically be concluded that the localized frictional heat of rapid fracture and/or spontaneous oxidation (exothermic) of minute particles emanating from the fracture cause initiation of the reaction. Under conditions of slow fracture, however, the small heat generated may be adequately dissipated and the reaction is not initiated. A portion of the study conducted consisted of investigating various means by which the reaction might be retarded or prevented. Providing a "barrier" at the titanium-oxygen interface consisting of either aluminum metal or a coating of a petroleum base corrosion inhibitor appeared to be only partially effective in retarding the reaction. The accidental puncturing or similar rupturing of thin-walled pressurized oxygen tanks on missiles and space vehicle will usually constitute loss of function, and may sometimes cause their catastrophic destruction

[Dislocated fracture of the lesser trochanter with malrotation of the stem after robot assisted implantation of a cementless hip prosthesis: a casuistic report].

PubMed

Prymka, M; Hassenpflug, J

2003-08-01

This paper presents the case of a 63 year old female with a severe coxarthrosis. She got a robot assited implantation of a cementless hip prosthesis (Osteolock, Stryker-Howmedica, Mühlheim). As operation robot the CASPAR-System (Orto-Maquet, Rastatt) was used. Initially, the clinical progress of the patient was fine. She was nearly painfree within 14 days and showed an acceptable range of motion in the operated joint (flexion/ extension 90 degrees /05 degrees /00 degrees ). She was mobilized with crutches and 15 kg weight bearing at the operated leg. 3 weeks postoperative the patient complaint about increasing pain without trauma or intensification of the weight bearing. X-rays showed not only a dislocated fracture of the lesser trochanter, but also a sinking combined with a malrotation of the stem. A revision operation was necessary,where we implanted a cemented stem. Now clinical progress was completely satisfying.

Producing Foils From Direct Cast Titanium Alloy Strip

NASA Technical Reports Server (NTRS)

Stuart, T. A.; Gaspar, T. A.; Sukonnik, I. M.; Semiatan, S. L.; Batawi, E.; Peters, J. A.; Fraser, H. L.

1996-01-01

This research was undertaken to demonstrate the feasibility of producing high-quality, thin-gage, titanium foil from direct cast titanium strip. Melt Overflow Rapid Solidification Technology (MORST) was used to cast several different titanium alloys into 500 microns thick strip, 10 cm wide and up to 3 m long. The strip was then either ground, hot pack rolled or cold rolled, as appropriate, into foil. Gamma titanium aluminide (TiAl) was cast and ground to approximately 100 microns thick foil and alpha-2 titanium aluminide (Ti3AI) was cast and hot pack rolled to approximately 70 microns thick foil. CP Ti, Ti6Al2Sn4Zr2Mo, and Ti22AI23Nb (Orthorhombic), were successfully cast and cold-rolled into good quality foil (less than 125 microns thick). The foils were generally fully dense with smooth surfaces, had fine, uniform microstructures, and demonstrated mechanical properties equivalent to conventionally produced titanium. By eliminating many manufacturing steps, this technology has the potential to produce thin gage, titanium foil with good engineering properties at significantly reduced cost relative to conventional ingot metallurgy processing.

Gold-nickel-titanium brazing alloy

DOEpatents

Mizuhara, Howard

1995-01-03

A brazing alloy in accordance with this invention has the following composition, by weight: 91 to 99 gold, 0.5 to 7% nickel; 0.10 to 2% titanium. Alternatively, with palladium present, the composition is as follows, by weight: 83 to 96% gold; 3 to 10% palladium; 0.5 to 5% nickel; 0.10 to 2% titanium.

Gold-nickel-titanium brazing alloy

DOEpatents

Mizuhara, Howard

1990-07-03

A brazing alloy in accordance with this invention has the following composition, by weight: 91 to 99% gold, 0.5 to 7% nickel; 0.10 to 2% titanium. Alternatively, with palladium present, the composition is as follows, by weight: 83 to 96% gold; 3 to 10% palladium; 0.5 to 5% nickel; 0.10 to 2% titanium.

Heat Flow Contours and Well Data Around the Milford FORGE Site

DOE Data Explorer

Joe Moore

2016-03-09

This submission contains a shapefile of heat flow contour lines around the FORGE site located in Milford, Utah. The model was interpolated from data points in the Milford_wells shapefile. This heat flow model was interpolated from 66 data points using the kriging method in Geostatistical Analyst tool of ArcGIS. The resulting model was smoothed 100%. The well dataset contains 59 wells from various sources, with lat/long coordinates, temperature, quality, basement depth, and heat flow. This data was used to make models of the specific characteristics.

40 CFR 721.10031 - Lithium potassium titanium oxide.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Lithium potassium titanium oxide. 721... Substances § 721.10031 Lithium potassium titanium oxide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as lithium potassium titanium oxide (PMN P-02...

40 CFR 721.10031 - Lithium potassium titanium oxide.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Lithium potassium titanium oxide. 721... Substances § 721.10031 Lithium potassium titanium oxide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as lithium potassium titanium oxide (PMN P-02...

40 CFR 721.10031 - Lithium potassium titanium oxide.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Lithium potassium titanium oxide. 721... Substances § 721.10031 Lithium potassium titanium oxide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as lithium potassium titanium oxide (PMN P-02...

40 CFR 721.10031 - Lithium potassium titanium oxide.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Lithium potassium titanium oxide. 721... Substances § 721.10031 Lithium potassium titanium oxide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as lithium potassium titanium oxide (PMN P-02...

40 CFR 721.10031 - Lithium potassium titanium oxide.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Lithium potassium titanium oxide. 721... Substances § 721.10031 Lithium potassium titanium oxide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as lithium potassium titanium oxide (PMN P-02...

Iron-titanium-mischmetal alloys for hydrogen storage

DOEpatents

Sandrock, Gary Dale

1978-01-01

A method for the preparation of an iron-titanium-mischmetal alloy which is used for the storage of hydrogen. The alloy is prepared by air-melting an iron charge in a clay-graphite crucible, adding titanium and deoxidizing with mischmetal. The resultant alloy contains less than about 0.1% oxygen and exhibits a capability for hydrogen sorption in less than half the time required by vacuum-melted, iron-titanium alloys.

Process for preparing fine grain titanium carbide powder

DOEpatents

Janney, M.A.

1985-03-12

A method for preparing finely divided titanium carbide powder in which an organotitanate is reacted with a carbon precursor polymer to provide an admixture of the titanium and the polymer at a molecular level due to a crosslinking reaction between the organotitanate and the polymer. The resulting gel is dried, pyrolyzed to drive off volatile components and provide carbon. The resulting solids are then heated at an elevated temperature to convert the titanium and carbon to high-purity titanium carbide powder in a submicron size range.

Process for preparing fine grain titanium carbide powder

DOEpatents

Janey, Mark A.

1986-01-01

A method for preparing finely divided titanium carbide powder in which an organotitanate is reacted with a carbon precursor polymer to provide an admixture of the titanium and the polymer at a molecular-level due to a crosslinking reaction between the organotitanate and the polymer. The resulting gel is dried, pyrolyzed to drive off volatile components and provide carbon. The resulting solids are then heated at an elevated temperature to convert the titanium and carbon to high-purity titanium carbide powder in a submicron size range.

Novel antioxidant capability of titanium induced by UV light treatment.

PubMed

Ueno, Takeshi; Ikeda, Takayuki; Tsukimura, Naoki; Ishijima, Manabu; Minamikawa, Hajime; Sugita, Yoshihiko; Yamada, Masahiro; Wakabayashi, Noriyuki; Ogawa, Takahiro

2016-11-01

The intracellular production of reactive oxygen species (ROS) is a representative form of cellular oxidative stress and plays an important role in triggering adverse cellular events, such as the inflammatory reaction and delayed or compromised differentiation. Osteoblastic reaction to titanium with particular focus on ROS production remains unknown. Ultraviolet (UV) light treatment improves the physicochemical properties of titanium, specifically the induction of super hydrophilicity and removal of hydrocarbon, and eventually enhances its osteoconductivity. We hypothesized that there is a favorable regulatory change of ROS production within osteoblasts in contact with UV-treated titanium. Osteoblasts were cultured on titanium disks with or without UV-pretreatment. The intracellular production of ROS was higher on acid-etch-created rough titanium surfaces than on machine-prepared smooth ones. The ROS production was reduced by 40-50% by UV pretreatment of titanium regardless of the surface roughness. Oxidative DNA damage, as detected by 8-OHdG expression, was alleviated by 50% on UV-treated titanium surfaces. The expression of inflammatory cytokines was consistently lower in osteoblasts cultured on UV-treated titanium. ROS scavenger, glutathione, remained more without being depleted in osteoblasts on UV-treated titanium. Bio-burden test further showed that culturing osteoblasts on UV-treated titanium can significantly reduce the ROS production even with the presence of hydrogen peroxide, an oxidative stress inducer. These data suggest that the intracellular production of ROS and relevant inflammatory reaction, which unavoidably occurs in osteoblasts in contact with titanium, can be significantly reduced by UV pretreatment of titanium, implying a novel antioxidant capability of the particular titanium. Copyright © 2016 Elsevier Ltd. All rights reserved.

Method for producing titanium aluminide weld rod

DOEpatents

Hansen, Jeffrey S.; Turner, Paul C.; Argetsinger, Edward R.

1995-01-01

A process for producing titanium aluminide weld rod comprising: attaching one end of a metal tube to a vacuum line; placing a means between said vacuum line and a junction of the metal tube to prevent powder from entering the vacuum line; inducing a vacuum within the tube; placing a mixture of titanium and aluminum powder in the tube and employing means to impact the powder in the tube to a filled tube; heating the tube in the vacuum at a temperature sufficient to initiate a high-temperature synthesis (SHS) reaction between the titanium and aluminum; and lowering the temperature to ambient temperature to obtain a intermetallic titanium aluminide alloy weld rod.

Ball bearings comprising nickel-titanium and methods of manufacture thereof

NASA Technical Reports Server (NTRS)

DellaCorte, Christopher (Inventor); Glennon, Glenn N. (Inventor)

2012-01-01

Disclosed herein is a friction reducing nickel-titanium composition. The nickel-titanium composition includes a first phase that comprises nickel and titanium in an atomic ratio of about 0.45:0.55 to about 0.55:0.45; a second phase that comprises nickel and titanium in an atomic ratio of about 0.70:0.30 to about 0.80:0.20; and a third phase that comprises nickel and titanium in an atomic ratio of about 0.52:0.48 to about 0.62:0.38. A bearing for reducing friction comprising a nickel-titanium composition comprising a first phase that comprises nickel and titanium in an atomic ratio of about 0.45:0.55 to about 0.55:0.45; a second phase that comprises nickel and titanium in an atomic ratio of about 0.70:0.30 to about 0.80:0.20; and a third phase that comprises nickel and titanium in an atomic ratio of about 0.52:0.48 to about 0.62:0.38; where the bearing is free from voids and pinholes.

The crevice corrosion of cathodically modified titanium in chloride solutions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lingen, E. van der

1995-12-01

The susceptibility of titanium to crevice corrosion in low-pH chloride solutions at elevated temperatures can result in major practical problems. Although Grade 7 titanium is considered the most crevice-corrosion resistant material available for these environments, the price increase of palladium has limited the utilization of this alloy. A cost-effective titanium alloy, containing 0.2% ruthenium by mass, has been developed for use in environments of increased chloride concentration and temperature. The crevice corrosion resistance of the Ti-0.2% Ru alloy has been evaluated and compared with that of ASTM commercially pure Grade 2 titanium, Grade 7 titanium (Ti-0.12 to 0.25% palladium bymore » mass) and Grade 12 titanium (Ti-0.8% Ni-0.3% Mo). The results indicated that the cathodically modified titanium alloys, Ti-0.2% Ru and Grade 7 titanium, showed similar resistance to crevice corrosion attack in all the solutions tested, and that their behavior was significantly better than that of Grade 2 and Grade 12 titanium.« less

21 CFR 73.2575 - Titanium dioxide.

Code of Federal Regulations, 2010 CFR

2010-04-01

... consistent with good manufacturing practice. (c) Labeling requirements. The color additive and any mixtures... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2575 Titanium dioxide. (a) Identity and specifications. The color additive titanium dioxide shall conform in identity and specifications to the requirements...

Taking the Lead in Science Education: Forging Next-Generation Science Standards. International Science Benchmarking Report. Appendix

ERIC Educational Resources Information Center

Achieve, Inc., 2010

2010-01-01

This appendix accompanies the report "Taking the Lead in Science Education: Forging Next-Generation Science Standards. International Science Benchmarking Report," a study conducted by Achieve to compare the science standards of 10 countries. This appendix includes the following: (1) PISA and TIMSS Assessment Rankings; (2) Courses and…

Corrosive effects of fluoride on titanium under artificial biofilm.

PubMed

Fukushima, Azusa; Mayanagi, Gen; Sasaki, Keiichi; Takahashi, Nobuhiro

2018-01-01

This study aimed to investigate the effect of sodium fluoride (NaF) on titanium corrosion using a biofilm model, taking environmental pH into account. Streptococcus mutans cells were used as the artificial biofilm, and pH at the bacteria-titanium interface was monitored after the addition of 1% glucose with NaF (0, 225 or 900ppmF) at 37°C for 90min. In an immersion test, the titanium samples were immersed in the NaF solution (0, 225 or 900ppm F; pH 4.2 or 6.5) for 30 or 90min. Before and after pH monitoring or immersion test, the electrochemical properties of the titanium surface were measured using a potentiostat. The amount of titanium eluted into the biofilm or the immersion solution was measured using inductively coupled plasma mass spectrometry. The color difference (ΔE*ab) and gloss of the titanium surface were determined using a spectrophotometer. After incubation with biofilm, pH was maintained at around 6.5 in the presence of NaF. There was no significant change in titanium surface and elution, regardless of the concentration of NaF. After immersion in 900ppm NaF solution at pH 4.2, corrosive electrochemical change was induced on the surface, titanium elution and ΔE*ab were increased, and gloss was decreased. NaF induces titanium corrosion in acidic environment in vitro, while NaF does not induce titanium corrosion under the biofilm because fluoride inhibits bacterial acid production. Neutral pH fluoridated agents may still be used to protect the remaining teeth, even when titanium-based prostheses are worn. Copyright © 2017 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

Cadmium Telluride-Titanium Dioxide Nanocomposite for Photodegradation of Organic Substance.

PubMed

Ontam, Areeporn; Khaorapapong, Nithima; Ogawa, Makoto

2015-12-01

Cadmium telluride-titanium dioxide nanocomposite was prepared by hydrothermal reaction of sol-gel derived titanium dioxide and organically modified cadmium telluride. The crystallinity of titanium dioxide in the nanocomposite was higher than that of pure titanium dioxide obtained by the reaction under the same temperature and pressure conditions, showing that cadmium telluride induced the crystallization of titanium dioxide. Diffuse reflectance spectrum of the nanocomposite showed the higher absorption efficiency in the UV-visible region due to band-gap excitation of titanium dioxide. The nanocomposite significantly showed the improvement of photocatalytic activity for 4-chlorophenol with UV light.

In vivo implant fixation of carbon fiber-reinforced PEEK hip prostheses in an ovine model.

PubMed

Nakahara, Ichiro; Takao, Masaki; Bandoh, Shunichi; Bertollo, Nicky; Walsh, William R; Sugano, Nobuhiko

2013-03-01

Carbon fiber-reinforced polyetheretherketone (CFR/PEEK) is theoretically suitable as a material for use in hip prostheses, offering excellent biocompatibility, mechanical properties, and the absence of metal ions. To evaluate in vivo fixation methods of CFR/PEEK hip prostheses in bone, we examined radiographic and histological results for cementless or cemented CFR/PEEK hip prostheses in an ovine model with implantation up to 52 weeks. CFR/PEEK cups and stems with rough-textured surfaces plus hydroxyapatite (HA) coatings for cementless fixation and CFR/PEEK cups and stems without HA coating for cement fixation were manufactured based on ovine computed tomography (CT) data. Unilateral total hip arthroplasty was performed using cementless or cemented CFR/PEEK hip prostheses. Five cementless cups and stems and six cemented cups and stems were evaluated. On the femoral side, all cementless stems demonstrated bony ongrowth fixation and all cemented stems demonstrated stable fixation without any gaps at both the bone-cement and cement-stem interfaces. All cementless cases and four of the six cemented cases showed minimal stress shielding. On the acetabular side, two of the five cementless cups demonstrated bony ongrowth fixation. Our results suggest that both cementless and cemented CFR/PEEK stems work well for fixation. Cup fixation may be difficult for both cementless and cemented types in this ovine model, but bone ongrowth fixation on the cup was first seen in two cementless cases. Cementless fixation can be achieved using HA-coated CFR/PEEK implants, even under load-bearing conditions. Copyright © 2012 Orthopaedic Research Society.

An Insoluble Titanium-Lead Anode for Sulfate Electrolytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ferdman, Alla

2005-05-11

The project is devoted to the development of novel insoluble anodes for copper electrowinning and electrolytic manganese dioxide (EMD) production. The anodes are made of titanium-lead composite material produced by techniques of powder metallurgy, compaction of titanium powder, sintering and subsequent lead infiltration. The titanium-lead anode combines beneficial electrochemical behavior of a lead anode with high mechanical properties and corrosion resistance of a titanium anode. In the titanium-lead anode, the titanium stabilizes the lead, preventing it from spalling, and the lead sheathes the titanium, protecting it from passivation. Interconnections between manufacturing process, structure, composition and properties of the titanium-lead compositemore » material were investigated. The material containing 20-30 vol.% of lead had optimal combination of mechanical and electrochemical properties. Optimal process parameters to manufacture the anodes were identified. Prototypes having optimized composition and structure were produced for testing in operating conditions of copper electrowinning and EMD production. Bench-scale, mini-pilot scale and pilot scale tests were performed. The test anodes were of both a plate design and a flow-through cylindrical design. The cylindrical anodes were composed of cylinders containing titanium inner rods and fitting over titanium-lead bushings. The cylindrical design allows the electrolyte to flow through the anode, which enhances diffusion of the electrolyte reactants. The cylindrical anodes demonstrate higher mass transport capabilities and increased electrical efficiency compared to the plate anodes. Copper electrowinning represents the primary target market for the titanium-lead anode. A full-size cylindrical anode performance in copper electrowinning conditions was monitored over a year. The test anode to cathode voltage was stable in the 1.8 to 2.0 volt range. Copper cathode morphology was very smooth and uniform. There

Comparative in vitro biocompatibility of nickel-titanium, pure nickel, pure titanium, and stainless steel: genotoxicity and atomic absorption evaluation.

PubMed

Assad, M; Lemieux, N; Rivard, C H; Yahia, L H

1999-01-01

The genotoxicity level of nickel-titanium (NiTi) was compared to that of its pure constituents, pure nickel (Ni) and pure titanium (Ti) powders, and also to 316L stainless steel (316L SS) as clinical reference material. In order to do so, a dynamic in vitro semiphysiological extraction was performed with all metals using agitation and ISO requirements. Peripheral blood lymphocytes were then cultured in the presence of all material extracts, and their comparative genotoxicity levels were assessed using electron microscopy-in situ end-labeling (EM-ISEL) coupled to immunogold staining. Cellular chromatin exposition to pure Ni and 316L SS demonstrated a significantly stronger gold binding than exposition to NiTi, pure Ti, or the untreated control. In parallel, graphite furnace atomic absorption spectrophotometry (AAS) was also performed on all extraction media. The release of Ni atoms took the following decreasing distribution for the different resulting semiphysiological solutions: pure Ni, 316L SS, NiTi, Ti, and controls. Ti elements were detected after elution of pure titanium only. Both pure titanium and nickel-titanium specimens obtained a relative in vitro biocompatibility. Therefore, this quantitative in vitro study provides optimistic results for the eventual use of nickel-titanium alloys as surgical implant materials.

Manufacturing of composite titanium-titanium nitride coatings by reactive very low pressure plasma spraying (R-VLPPS)

NASA Astrophysics Data System (ADS)

Vautherin, B.; Planche, M.-P.; Quet, A.; Bianchi, L.; Montavon, G.

2014-11-01

Very Low Pressure Plasma Spraying (VLPPS) is an emerging spray process nowadays intensively studied by many research centers in the World. To date, studies are mostly focused on the manufacturing of ceramic or metallic coatings. None refers to composite coatings manufacturing by reactive plasma spraying under very low pressure (i.e., ~150 Pa). This paper aims at presenting the carried-out developments and some results concerning the manufacturing of composite coatings by reactive spraying. Titanium was selected as metallic material in order to deposit titanium-nitride titanium coatings (Ti-TiN). Nitrogen was used as plasma gas and was injected along an Ar-H2-N2 plasma jet via a secondary injector in order to reach the nitrogen content on the substrate surface. Thus, different kind of reactive mechanisms were highlighted. Resulting coatings were characterized by Scanning Electron Microscopy (SEM) observations. Porous microstructures are clearly identified and the deposits exhibit condensed vapours and molten particles. Glow Discharge Optical Emission Spectroscopy (GDOES) analysis evidenced nitrogen inside the deposits and X-Ray Diffraction (XRD) analysis confirmed the formation of titanium nitride phases, such as TiN and Ti2N, depending upon the location of the nitrogen injection. Microhardness values as high as 800 VHN were measured on manufactured samples (to be compared to 220 VHN for pure titanium VLPPS-manufactured coatings).

Research on tool wearing on milling of TC21 titanium alloy

NASA Astrophysics Data System (ADS)

Guilin, Liu

2017-06-01

Titanium alloys are used in aircraft widely, but the efficiency is a problem for machining titanium alloy. In this paper, the cutting experiment of TC21 titanium alloy was studied. Cutting parameters and test methods for TC21 titanium alloy were designed. The wear behavior of TC21 titanium alloy was studied based on analysis of orthogonal test results. It provides a group of cutting parameters for TC21 titanium alloy processing.

Method for preparing hydrous titanium oxide spherules and other gel forms thereof

DOEpatents

Collins, J.L.

1998-10-13

The present invention are methods for preparing hydrous titanium oxide spherules, hydrous titanium oxide gels such as gel slabs, films, capillary and electrophoresis gels, titanium monohydrogen phosphate spherules, hydrous titanium oxide spherules having suspendible particles homogeneously embedded within to form a composite sorbent, titanium monohydrogen phosphate spherules having suspendible particles of at least one different sorbent homogeneously embedded within to form a composite sorbent having a desired crystallinity, titanium oxide spherules in the form of anatase, brookite or rutile, titanium oxide spherules having suspendible particles homogeneously embedded within to form a composite, hydrous titanium oxide fiber materials, titanium oxide fiber materials, hydrous titanium oxide fiber materials having suspendible particles homogeneously embedded within to form a composite, titanium oxide fiber materials having suspendible particles homogeneously embedded within to form a composite and spherules of barium titanate. These variations of hydrous titanium oxide spherules and gel forms prepared by the gel-sphere, internal gelation process offer more useful forms of inorganic ion exchangers, catalysts, getters and ceramics. 6 figs.

Method for preparing hydrous titanium oxide spherules and other gel forms thereof

DOEpatents

Collins, Jack L.

1998-01-01

The present invention are methods for preparing hydrous titanium oxide spherules, hydrous titanium oxide gels such as gel slabs, films, capillary and electrophoresis gels, titanium monohydrogen phosphate spherules, hydrous titanium oxide spherules having suspendible particles homogeneously embedded within to form a composite sorbent, titanium monohydrogen phosphate spherules having suspendible particles of at least one different sorbent homogeneously embedded within to form a composite sorbent having a desired crystallinity, titanium oxide spherules in the form of anatase, brookite or rutile, titanium oxide spherules having suspendible particles homogeneously embedded within to form a composite, hydrous titanium oxide fiber materials, titanium oxide fiber materials, hydrous titanium oxide fiber materials having suspendible particles homogeneously embedded within to form a composite, titanium oxide fiber materials having suspendible particles homogeneously embedded within to form a composite and spherules of barium titanate. These variations of hydrous titanium oxide spherules and gel forms prepared by the gel-sphere, internal gelation process offer more useful forms of inorganic ion exchangers, catalysts, getters and ceramics.

Activation of Osteoblastic Function on Titanium Surface with Titanium-Doped Hydroxyapatite Nanoparticle Coating: An In Vitro Study.

PubMed

Nakazawa, Masahiro; Yamada, Masahiro; Wakamura, Masato; Egusa, Hiroshi; Sakurai, Kaoru

Titanium-doped hydroxyapatite (TiHA) nanoparticles contain titanium atoms in the hydroxyapatite lattice, which can physicochemically functionalize the titanium surface without modification of the surface topography. This study aimed to evaluate the physicochemical properties of machined or microroughened titanium surfaces coated with TiHA nanoparticles and the functions of osteoblasts cultured on them. Titanium disks with commercially available surface topography, such as machined or sandblasted, large-grit, and acid-etched (SLA) surfaces, were coated with TiHA. The disks with original or TiHA-coated surfaces were evaluated in topography, wettability, and chemical composition. Osteoblastic cells from rat femurs were cultured on the disks and evaluated in proliferation and differentiation. TiHA coating changed from hydrophobicity to hydrophilicity on both machined and SLA surfaces. Calcium and phosphate atoms were detected all over the surface with TiHA coating regardless of the surface topography. However, the considerable change in the inherent surface topographies was not observed on both types of surfaces after TiHA coating. Osteoblastic proliferative activity at day 4 was increased by TiHA coating on both types of surfaces. TiHA coating did not enhance expressions of bone matrix-related genes such as osteocalcin, osteopontin, bone sialoprotein, alkaline phosphatase, and collagen I. However, depositions of collagen, osteocalcin, and calcium in the culture at days 7 and 20 were increased on both types of surface topographies with TiHA coating. TiHA coating enhanced extracellular matrix formation on smooth and microroughened titanium surfaces by increasing osteoblastic proliferative activity without the deterioration of differentiation through hydrophilic and chemical functionalization.

Manufacturing techniques for titanium aluminide based alloys and metal matrix composites

NASA Astrophysics Data System (ADS)

Kothari, Kunal B.

Dual phase titanium aluminides composed vastly of gamma phase (TiAl) with moderate amount of alpha2 phase (Ti3Al) have been considered for several high temperature aerospace and automobile applications. High specific strength coupled with good high temperature performance in the areas of creep and oxidation resistance makes titanium aluminides "materials of choice" for next generation propulsion systems. Titanium alumnides are primarily being considered as potential replacements for Ni-based superalloys in gas turbine engine components with aim of developing more efficient and leaner engines exhibiting high thrust-to-weight ratio. Thermo-mechanical treatments have shown to enhance the mechanical performance of titanium aluminides. Additionally, small additions of interstitial elements have shown further and significant improvement in the mechanical performance of titanium alumnide alloys. However, titanium aluminides lack considerably in room temperature ductility and as a result manufacturing processes of these aluminides have greatly suffered. Traditional ingot metallurgy and investment casting based methods to produce titanium aluminide parts in addition to being expensive, have also been unsuccessful in producing titanium aluminides with the desired mechanical properties. Hence, the manufacturing costs associated with these methods have completely outweighed the benefits offered by titanium aluminides. Over the last two decades, several powder metallurgy based manufacturing techniques have been studied to produce titanium aluminide parts. These techniques have been successful in producing titanium aluminide parts with a homogeneous and refined microstructure. These powder metallurgy techniques also hold the potential of significant cost reduction depending on the wide market acceptance of titanium aluminides. In the present study, a powder metallurgy based rapid consolidation technique has been used to produce near-net shape parts of titanium aluminides. Micron

Enhanced Cellular Adhesion on Titanium by Silk Functionalized with titanium binding and RGD peptides

PubMed Central

Vidal, Guillaume; Blanchi, Thomas; Mieszawska, Aneta J.; Calabrese, Rossella; Rossi, Claire; Vigneron, Pascale; Duval, Jean-Luc; Kaplan, David L.; Egles, Christophe

2012-01-01

Soft tissue adhesion on titanium represents a challenge for implantable materials. In order to improve adhesion at the cell/material interface we used a new approach based on the molecular recognition of titanium by specific peptides. Silk fibroin protein was chemically grafted with titanium binding peptide (TiBP) to increase adsorption of these chimeric proteins to the metal surface. Quartz Crystal Microbalance was used to quantify the specific adsorption of TiBP-functionalized silk and an increase in protein deposition by more than 35% was demonstrated due to the presence of the binding peptide. A silk protein grafted with TiBP and fibronectin-derived RGD peptide was then prepared. The adherence of fibroblasts on the titanium surface modified with the multifunctional silk coating demonstrated an increase in the number of adhering cells by 60%. The improved adhesion was demonstrated by Scanning Electron Microscopy and immunocytochemical staining of focal contact points. Chick embryo organotypic culture also revealed strong adhesion of endothelial cells expanding on the multifunctional silk-peptide coating. These results demonstrated that silk functionalized with TiBP and RGD represents a promising approach to modify cell-biomaterial interfaces, opening new perspectives for implantable medical devices, especially when reendothelialization is required. PMID:22975628

On the Effects of Hot Forging and Hot Rolling on the Microstructural Development and Mechanical Response of a Biocompatible Ti Alloy

PubMed Central

Okazaki, Yoshimitsu

2012-01-01

Zr, Nb, and Ta as alloying elements for Ti alloys are important for attaining superior corrosion resistance and biocompatibility in the long term. However, note that the addition of excess Nb and Ta to Ti alloys leads to higher manufacturing cost. To develop low-cost manufacturing processes, the effects of hot-forging and continuous-hot-rolling conditions on the microstructure, mechanical properties, hot forgeability, and fatigue strength of Ti-15Zr-4Nb-4Ta alloy were investigated. The temperature dependences with a temperature difference (ΔT) from β-transus temperature (Tβ) for the volume fraction of the α- and β-phases were almost the same for both Ti-15Zr-4Nb-4Ta and Ti-6Al-4V alloys. In the α-β-forged Ti-15Zr-4Nb-4Ta alloy, a fine granular α-phase structure containing a fine granular β-phase at grain boundaries of an equiaxed α-phase was observed. The Ti-15Zr-4Nb-4Ta alloy billet forged at Tβ-(30 to 50) °C exhibited high strength and excellent ductility. The effects of forging ratio on mechanical strength and ductility were small at a forging ratio of more than 3. The maximum strength (σmax) markedly increased with decreasing testing temperature below Tβ. The reduction in area (R.A.) value slowly decreased with decreasing testing temperature below Tβ. The temperature dependences of σmax for the Ti-15Zr-4Nb-4Ta and Ti-6Al-4V alloys show the same tendency and might be caused by the temperature difference (ΔT) from Tβ. It was clarified that Ti-15Zr-4Nb-4Ta alloy could be manufactured using the same manufacturing process as for previously approved Ti-6Al-4V alloy, taking into account the difference (ΔT) between Tβ and heat treatment temperature. Also, the manufacturing equivalency of Ti-15Zr-4Nb-4Ta alloy to obtain marketing approval of implants was established. Thus, it was concluded that continuous hot rolling is useful for manufacturing α-β-type Ti alloy.

Lunar-derived titanium alloys for hydrogen storage

NASA Technical Reports Server (NTRS)

Love, S.; Hertzberg, A.; Woodcock, G.

1992-01-01

Hydrogen gas, which plays an important role in many projected lunar power systems and industrial processes, can be stored in metallic titanium and in certain titanium alloys as an interstitial hydride compound. Storing and retrieving hydrogen with titanium-iron alloy requires substantially less energy investment than storage by liquefaction. Metal hydride storage systems can be designed to operate at a wide range of temperatures and pressures. A few such systems have been developed for terrestrial applications. A drawback of metal hydride storage for lunar applications is the system's large mass per mole of hydrogen stored, which rules out transporting it from earth. The transportation problem can be solved by using native lunar materials, which are rich in titanium and iron.

Investigation of Conditions of Titanium Carbonization - IV

NASA Technical Reports Server (NTRS)

Meerson, G. A.; Lipkes, Y. M.

1949-01-01

In a previous paper, results are presented of accurate investigations of the processes of titanium carbonization and the succeeding titanium carbide decarbonization as related to the phenomenon of the graphitization of soot by heating at a constant temperature in atmospheres of pure hydrogen and carbon monoxide. These tests showed that the processes of titanium carbonization-decarbonization in an atmosphere of pure gases without nitrogen proceed in the same direction as the analogous processes under the conditions of the production furnace. In this case, however, the presence of admixtures of nitrogen changes the quantitative results of the decarbonization process. Thermodynamic computations confirming the results of previous tests conducted at atmospheric pressure and additional tests of titanium carbonization at lowered pressures are presented herein.

Fracture Mechanics Testing of Titanium 6AL-4V in AF-M315E

NASA Technical Reports Server (NTRS)

Sampson, J. W.; Martinez, J.; McLean, C.

2016-01-01

The Green Propellant Infusion Mission (GPIM) will demonstrate the performance of AF-M315E monopropellant on orbit. Flight certification requires a safe-life analysis of the titanium alloy fuel tank to ensure inherent processing flaws will not cause failure during the design life of the tank. Material property inputs for this analysis require testing to determine the stress intensity factor for environment-assisted cracking (KEAC) of Ti 6Al-4V in combination with the AF-M315E monopropellant. Testing of single-edge notched, or SE(B), specimens representing the bulk tank membrane and weld material were performed in accordance with ASTM E1681. Specimens with fatigue pre-cracks were loaded into test fixtures so that the crack tips were exposed to AF-M315E at 50 C for a duration of 1,000 hours. Specimens that did not fail during exposure were opened to inspect the crack surfaces for evidence of crack growth. The threshold stress intensity value, KEAC, is the highest applied stress intensity that produced neither a failure of the specimen during the exposure nor showed evidence of crack growth. The threshold stress intensity factor for environment-assisted cracking of the Ti 6Al-4V forged tank material was found to be at least 22 ksivin and at least 31 ksivin for the weld material when exposed to AF-M315E monopropellant.

Mineral resource of the month: titanium

USGS Publications Warehouse

Gambogi, Joseph

2011-01-01

Titanium is hip - at least when it comes to airplanes and jewelry. Known for its high strength-to weight ratio and its resistance to corrosion, titanium and its alloys can also be found in everything from knee replacements to eyeglass frames to baseball bats to fighter planes.

Bonding titanium to Rene 41 alloy

NASA Technical Reports Server (NTRS)

Scott, R. W.

1972-01-01

Pair of intermediate materials joined by electron beam welding method welds titanium to Rene 41 alloy. Bond is necessary for combining into one structure high strength-to-density ratio titanium fan blades and temperature resistant nickel-base alloy turbine-buckets in VTOL aircraft lift-fan rotor.

76 FR 24856 - Heavy Forged Hand Tools (i.e., Axes & Adzes, Bars & Wedges, Hammers & Sledges, and Picks...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-03

... DEPARTMENT OF COMMERCE International Trade Administration [A-570-803] Heavy Forged Hand Tools (i.e... Administration, International Trade Administration, Department of Commerce. SUMMARY: On January 3, 2011, the Department of Commerce (``Department'') initiated a sunset review of the antidumping duty orders on heavy...

Allergic contact dermatitis caused by titanium screws and dental implants.

PubMed

Hosoki, Maki; Nishigawa, Keisuke; Miyamoto, Youji; Ohe, Go; Matsuka, Yoshizo

2016-07-01

Titanium has been considered to be a non-allergenic material. However, several studies have reported cases of metal allergy caused by titanium-containing materials. We describe a 69-year-old male for whom significant pathologic findings around dental implants had never been observed. He exhibited allergic symptoms (eczema) after orthopedic surgery. The titanium screws used in the orthopedic surgery that he underwent were removed 1 year later, but the eczema remained. After removal of dental implants, the eczema disappeared completely. Titanium is used not only for medical applications such as plastic surgery and/or dental implants, but also for paints, white pigments, photocatalysts, and various types of everyday goods. Most of the usage of titanium is in the form of titanium dioxide. This rapid expansion of titanium-containing products has increased percutaneous and permucosal exposure of titanium to the population. In general, allergic risk of titanium material is smaller than that of other metal materials. However, we suggest that pre-implant patients should be asked about a history of hypersensitivity reactions to metals, and patch testing should be recommended to patients who have experienced such reactions. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Cold Spraying of Armstrong Process Titanium Powder for Additive Manufacturing

NASA Astrophysics Data System (ADS)

MacDonald, D.; Fernández, R.; Delloro, F.; Jodoin, B.

2017-04-01

Titanium parts are ideally suited for aerospace applications due to their unique combination of high specific strength and excellent corrosion resistance. However, titanium as bulk material is expensive and challenging/costly to machine. Production of complex titanium parts through additive manufacturing looks promising, but there are still many barriers to overcome before reaching mainstream commercialization. The cold gas dynamic spraying process offers the potential for additive manufacturing of large titanium parts due to its reduced reactive environment, its simplicity to operate, and the high deposition rates it offers. A few challenges are to be addressed before the additive manufacturing potential of titanium by cold gas dynamic spraying can be reached. In particular, it is known that titanium is easy to deposit by cold gas dynamic spraying, but the deposits produced are usually porous when nitrogen is used as the carrier gas. In this work, a method to manufacture low-porosity titanium components at high deposition efficiencies is revealed. The components are produced by combining low-pressure cold spray using nitrogen as the carrier gas with low-cost titanium powder produced using the Armstrong process. The microstructure and mechanical properties of additive manufactured titanium components are investigated.

Biocorrosion study of titanium-cobalt alloys.

PubMed

Chern Lin, J H; Lo, S J; Ju, C P

1995-05-01

The present work provides experimental results of corrosion behaviour in Hank's physiological solution and some other properties of in-house fabricated titanium-cobalt alloys with cobalt ranging from 25-30% in weight. X-ray diffraction (XRD) shows that, in water-quenched (WQ) alloys, beta-titanium is largely retained, whereas in furnace-cooled (FC) alloys, little beta-titanium is found. Hardness of the alloys increases with increasing cobalt content, ranging from 455 VHN for WQ Ti-25 wt% Co to 525 VHN for WQ Ti-30 wt% Co. Differential thermal analysis (DTA) indicates that melting temperatures of the alloys are lower than that of pure titanium by about 600 degrees C. Potentiodynamic polarization results show that all measured break-down potentials in Hank's solution at 37 degrees C are higher than 800 mV. The breakdown potential for the FC Ti-25 Wt% Co alloy is even as high as nearly 1200 mV.

Detection of titanium in human tissues after craniofacial surgery.

PubMed

Jorgenson, D S; Mayer, M H; Ellenbogen, R G; Centeno, J A; Johnson, F B; Mullick, F G; Manson, P N

1997-04-01

Generally, titanium fixation plates are not removed after osteosynthesis, because they have high biocompatability and high corrosion resistance characteristics. Experiments with laboratory animals, and limited studies of analyses of human tissues, have reported evidence of titanium release into local and distant tissues. This study summarizes our results of the analysis of soft tissues for titanium in four patients with titanium microfixation plates. Energy dispersive x-ray analysis, scanning electron microscopy, and electrothermal atomic absorption spectrophotometry were used to detect trace amounts of titanium in surrounding soft tissues. A single metal inclusion was detected by scanning electron microscopy and energy dispersive x-ray analysis in one patient, whereas, electrothermal atomic absorption spectrophotometry analyses revealed titanium present in three of four specimens in levels ranging from 7.92 to 31.8 micrograms/gm of dry tissue. Results from this study revealed trace amounts of titanium in tissues surrounding craniofacial plates. At the atomic level, electrothermal atomic absorption spectrophotometry appears to be a sensitive tool to quantitatively detect ultra-trace amounts of metal in human tissue.

Snake River Plain FORGE Well Data for INEL-1

DOE Data Explorer

Robert Podgorney

1979-03-01

Well data for the INEL-1 well located in eastern Snake River Plain, Idaho. This data collection includes caliper logs, lithology reports, borehole logs, temperature at depth data, neutron density and gamma data, full color logs, fracture analysis, photos, and rock strength parameters for the INEL-1 well. This collection of data has been assembled as part of the site characterization data used to develop the conceptual geologic model for the Snake River Plain site in Idaho, as part of phase 1 of the Frontier Observatory for Research in Geothermal Energy (FORGE) initiative. They were assembled by the Snake River Geothermal Consortium (SRGC), a team of collaborators that includes members from national laboratories, universities, industry, and federal agencies, lead by the Idaho National Laboratory (INL).

Well Acord 1-26 Logs and Data: Roosevelt Hot Spring Area, Utah (Utah FORGE)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Joe Moore

This is a compilation of logs and data from Well Acord 1-26 in the Roosevelt Hot Springs area in Utah. This well is also in the Utah FORGE study area. The file is in a compressed .zip format and there is a data inventory table (Excel spreadsheet) in the root folder that is a guide to the data that is accessible in subfolders.

Vanadium-pumped titanium x-ray laser

DOEpatents

Nilsen, J.

1992-05-26

A resonantly photo-pumped x-ray laser is formed of a vanadium and titanium foil combination that is driven by two beams of intense line focused optical laser radiation. Ground state neon-like titanium ions are resonantly photo-pumped by line emission from fluorine-like vanadium ions. 4 figs.

Titanium tetrafluoride and dental caries: a systematic review.

PubMed

Alves, Rubiane Diógenes; Souza, Tatyana Maria Silva de; Lima, Kenio Costa de

2005-12-01

The aim of this systematic review was to evaluate the effectiveness of titanium tetrafluoride as a preventive or cariostatic agent against caries. The databases used to find the articles analyzed were MEDLINE LILACS, and BBO. In MEDLINE and LILACS the search strategy utilized was "titanium" [Words] and "tetrafluoride" [Words] and Spanish or English or Portuguese [Language], whereas In BBO "titânio" [Words] and "tetrafluoreto" [Words] and Espanhol or Inglês or Português [Language]. Out of a total of 42 studies found, which assessed possible preventive/cariostatic effects of titanium tetrafluoride against caries in vivo, only 2 were selected. In both studies, titanium tetrafluoride was shown to be effective against caries. However, given that the quality and consequently the validity of these two clinical studies are questionable, their results do not allow to conclude that titanium tetrafluoride is effective against caries clinically.

Porous titanium construct cup compared to porous coated titanium cup in total hip arthroplasty. A randomised controlled trial.

PubMed

Salemyr, Mats; Muren, Olle; Eisler, Thomas; Bodén, Henrik; Chammout, Ghazi; Stark, André; Sköldenberg, Olof

2015-05-01

The purpose of this study was to determine if a new titanium cup with increased porosity resulted in different periacetabular bone loss and migration compared to a porous coated cup. Fifty-one patients with primary hip osteoarthritis were randomized to either a cup with porous titanium construct backside (porous titanium group, n = 25) or a conventional porous coated titanium cup (control group, n = 26). The primary outcome variable was change in periacetabular bone mineral density two years after surgery measured with dual energy X-ray absorptiometry (DXA). Secondary outcomes were implant fixation measured with radiostereometry (RSA) and clinical outcome scores. The pattern of bone remodelling was similar in the two groups with almost complete restoration to baseline values. BMD diminished in the two proximal zones and increased in the two distal zones. After minimal migration up to six months all implants in both groups became stable. We found no difference between the two groups in clinical outcome scores. In this prospective, randomized, controlled trial on a new porous titanium cup we found, compared to the control group, no clinically relevant differences regarding periacetabular bone preservation, implant fixation or clinical outcome up to two years postoperatively.

Cerclage wires or cables for the management of intraoperative fracture associated with a cementless, tapered femoral prosthesis: results at 2 to 16 years.

PubMed

Berend, Keith R; Lombardi, Adolph V; Mallory, Thomas H; Chonko, Douglas J; Dodds, Kathleen L; Adams, Joanne B

2004-10-01

Initial stability is critical for fixation and survival of cementless total hip arthroplasty. Occasionally, a split of the calcar occurs intraoperatively. A review of 1,320 primary total hip arthroplasties with 2-year follow-up, performed between August 1985 and February 2001 using the Mallory-Head Porous tapered femoral component, revealed 58 hips in 55 patients with an intraoperative calcar fracture managed with single or multiple cerclage wires or cables and immediate full weight bearing. At 7.5 years average follow-up (range, 2-16 years), there were no revisions of the femoral component, radiographic failures, or patients with severe thigh pain, for a stem survival rate of 100%. Average Harris hip score improvement was 33.8 points. Fracture of the proximal femur occurs in approximately 4% of primary THAs using the Mallory-Head Porous femoral component. When managed intraoperatively with cerclage wire or cable, the mid- to long-term results appear unaffected with 100% femoral component survival at up to 16 years.

Low Temperature Superplasticity of Ti-6Al-4V Processed by Warm Multidirectional Forging (Preprint)

DTIC Science & Technology

2012-07-01

microstructure in the two-phase titanium alloy Ti- 6Al - 4V . A microstructure with a grain size of 135 nm was attained, enabling low-temperature...the / titanium alloy Ti- 6Al - 4V [3]. The great interest in microstructure refinement is associated with significantly reduced superplastic (SP...consisted of the / titanium alloy Ti- 6Al - 4V with a nominal composition (in weight pct.) of 6.3 Al, 4.1 V, 0.18 Fe, 0.03 Si, 0.02 Zr, 0.01 C, 0.18 O, 0.01 N

Custom-made laser-welded titanium implant prosthetic abutment.

PubMed

Iglesia-Puig, Miguel A

2005-10-01

A technique to create an individually modified implant prosthetic abutment is described. An overcasting is waxed onto a machined titanium abutment, cast in titanium, and joined to it with laser welding. With the proposed technique, a custom-made titanium implant prosthetic abutment is created with adequate volume and contour of metal to support a screw-retained, metal-ceramic implant-supported crown.

Titanium Corrosion: Implications For Dental Implants.

PubMed

Shah, Rucha; Penmetsa, Deepika Shree Lakshmi; Thomas, Raison; Mehta, Dhoom Singh

2016-12-01

Titanium has been considered as one of the most biocompatible metals. Studies testing its corrosion resistance have proposed that the titanium oxide layer formed on the metal surface is lost under certain unavoidable conditions to which it is exposed in the oral environment. This questions its property of corrosion resistance in the oral cavity. Hence, there is a need to understand the mechanisms of corrosion, which can help in the long-term stability and function of implants. Here, we review the possible pathways of corrosion of titanium in the oral cavity, its implications and proposed methods of prevention of corrosion. Copyright© 2016 Dennis Barber Ltd.

Stress corrosion cracking of titanium alloys

NASA Technical Reports Server (NTRS)

Statler, G. R.; Spretnak, J. W.; Beck, F. H.; Fontana, M. G.

1974-01-01

The effect of hydrogen on the properties of metals, including titanium and its alloys, was investigated. The basic theories of stress corrosion of titanium alloys are reviewed along with the literature concerned with the effect of absorbed hydrogen on the mechanical properties of metals. Finally, the basic modes of metal fracture and their importance to this study is considered. The experimental work was designed to determine the effects of hydrogen concentration on the critical strain at which plastic instability along pure shear directions occurs. The materials used were titanium alloys Ti-8Al-lMo-lV and Ti-5Al-2.5Sn.

Conventionally cast and forged copper alloy for high-heat-flux thrust chambers

NASA Technical Reports Server (NTRS)

Kazaroff, John M.; Repas, George A.

1987-01-01

The combustion chamber liner of the space shuttle main engine is made of NARloy-Z, a copper-silver-zirconium alloy. This alloy was produced by vacuum melting and vacuum centrifugal casting; a production method that is currently now available. Using conventional melting, casting, and forging methods, NASA has produced an alloy of the same composition called NASA-Z. This report compares the composition, microstructure, tensile properties, low-cycle fatigue life, and hot-firing life of these two materials. The results show that the materials have similar characteristics.

21 CFR 73.2575 - Titanium dioxide.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Titanium dioxide. 73.2575 Section 73.2575 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR.... The color additive titanium dioxide shall conform in identity and specifications to the requirements...

Influence of pore size of porous titanium fabricated by vacuum diffusion bonding of titanium meshes on cell penetration and bone ingrowth.

PubMed

Chang, Bei; Song, Wen; Han, Tianxiao; Yan, Jun; Li, Fuping; Zhao, Lingzhou; Kou, Hongchao; Zhang, Yumei

2016-03-01

The present work assesses the potential of three-dimensional (3D) porous titanium (pore size of 188-390 μm and porosity of 70%) fabricated by vacuum diffusion bonding of titanium meshes for applications in bone engineering. Rat bone marrow mesenchymal stem cells were used to investigate the proliferation and differentiation of cells on titanium scaffolds with different pore sizes at day 7, day 14 and day 21 based on DNA contents, alkaline phosphatase (ALP) activity, collagen (COL) secretion and osteogenic gene expressions including ALP, COL-1, bone morphogenetic protein-2 (BMP-2), osteopontin (OPN), runt-related transcription factor 2 (RUNX2), using smooth solid titanium plate as reference material. The rabbit models with distal femoral condyles defect were used to investigate the bone ingrowth into the porous titanium. All samples were subjected to Micro-CT and histological analysis after 4 and 12 weeks of healing. A one-way ANOVA followed by Tukey post hoc tests was used to analyze the data. It was found that the differentiation stage of cells on the porous titanium delayed compared with the smooth solid titanium plate and Ti 188 was more inclined to promote cell differentiation at the initial stage (day 14) while cell proliferation (day 1, 4, 7, 10, 14 and 21) and bone ingrowth (4 and 12 weeks) were biased to Ti 313 and Ti 390. The study indicates that the hybrid porous implant design which combines the advantages of different pore sizes may be meaningful and promising for bone defect restoration. One of the significant challenges in bone defect restoration is the integration of biomaterials and surrounding bone tissue. Porous titanium may be a promising choice for bone ingrowth and mineralization with appropriate mechanical and biological properties. In this study, based on porous titanium fabricated by vacuum diffusion bonding of titanium meshes, we have evaluated the influence of various pore sizes on rat bone marrow mesenchymal stem cells (r

Comparison of galvanic corrosion potential of metal injection molded brackets to that of conventional metal brackets with nickel-titanium and copper nickel-titanium archwire combinations.

PubMed

Varma, D Praveen Kumar; Chidambaram, S; Reddy, K Baburam; Vijay, M; Ravindranath, D; Prasad, M Rajendra

2013-05-01

The aim of the study is to investigate the galvanic corrosion potential of metal injection molding (MIM) brackets to that of conventional brackets under similar in vitro conditions with nickel-titanium and copper nickel-titanium archwires. Twenty-five maxillary premolar MIM stainless steel brackets and 25 conventional stainless steel brackets and archwires, 0.16 inch, each 10 mm length, 25 nickeltitanium wires, 25 copper nickel-titanium wires were used. They were divided into four groups which had five samples each. Combination of MIM bracket with copper nickel-titanium wire, MIM bracket with nickel-titanium wire and conventional stainless steel brackets with copper nickel-titanium wire and conventional stainless steel brackets with nickel-titanium wires which later were suspended in 350 ml of 1 M lactic acid solution media. Galvanic corrosion potential of four groups were analyzed under similar in vitro conditions. Precorrosion and postcorrosion elemental composition of MIM and conventional stainless steel bracket by scanning electron microscope (SEM) with energy dispersive spectroscope (EDS) was done. MIM bracket showed decreased corrosion susceptibility than conventional bracket with copper nickeltitanium wire. Both MIM and conventional bracket showed similar corrosion resistance potential in association with nickel-titanium archwires. It seems that both brackets are more compatible with copper nickel-titanium archwires regarding the decrease in the consequences of galvanic reaction. The EDS analysis showed that the MIM brackets with copper nickel-titanium wires released less metal ions than conventional bracket with copper nickeltitanium wires. MIM brackets showed decreased corrosion susceptibility, copper nickel-titanium archwires are compatible with both the brackets than nickel-titanium archwires. Clinically MIM and conventional brackets behaved more or less similarly in terms of corrosion resistance. In order to decrease the corrosion potential of MIM

Notch sensitivity jeopardizes titanium locking plate fatigue strength.

PubMed

Tseng, Wo-Jan; Chao, Ching-Kong; Wang, Chun-Chin; Lin, Jinn

2016-12-01

Notch sensitivity may compromise titanium-alloy plate fatigue strength. However, no studies providing head-to-head comparisons of stainless-steel or titanium-alloy locking plates exist. Custom-designed identically structured locking plates were made from stainless steel (F138 and F1314) or titanium alloy. Three screw-hole designs were compared: threaded screw-holes with angle edges (type I); threaded screw-holes with chamfered edges (type II); and non-threaded screw-holes with chamfered edges (type III). The plates' bending stiffness, bending strength, and fatigue life, were investigated. The stress concentration at the screw threads was assessed using finite element analyses (FEA). The titanium plates had higher bending strength than the F1314 and F138 plates (2.95:1.56:1) in static loading tests. For all metals, the type-III plate fatigue life was highest, followed by type-II and type-I. The type-III titanium plates had longer fatigue lives than their F138 counterparts, but the type-I and type-II titanium plates had significantly shorter fatigue lives. All F1314 plate types had longer fatigue lives than the type-III titanium plates. The FEA showed minimal stress difference (0.4%) between types II and III, but the stress for types II and III was lower (11.9% and 12.4%) than that for type I. The screw threads did not cause stress concentration in the locking plates in FEA, but may have jeopardized the fatigue strength, especially in the notch-sensitive titanium plates. Improvement to the locking plate design is necessary. Copyright © 2016 Elsevier Ltd. All rights reserved.

Does titanium in ionic form display a tissue-specific distribution?

PubMed

Golasik, Magdalena; Wrobel, Pawel; Olbert, Magdalena; Nowak, Barbara; Czyzycki, Mateusz; Librowski, Tadeusz; Lankosz, Marek; Piekoszewski, Wojciech

2016-06-01

Most studies have focused on the biodistribution of titanium(IV) oxide as nanoparticles or crystals in organism. But several reports suggested that titanium is released from implant in ionic form. Therefore, gaining insight into toxicokinetics of Ti ions will give valuable information, which may be useful when assessing the health risks of long-term exposure to titanium alloy implants in patients. A micro synchrotron radiation-induced X-ray fluorescence (µ-SRXRF) was utilized to investigate the titanium distribution in the liver, spleen and kidneys of rats following single intravenous or 30-days oral administration of metal (6 mg Ti/b.w.) in ionic form. Titanium was mainly retained in kidneys after both intravenous and oral dosing, and also its compartmentalization in this organ was observed. Titanium in the liver was non-uniformly distributed-metal accumulated in single aggregates, and some of them were also enriched in calcium. Correlation analysis showed that metal did not displace essential elements, and in liver titanium strongly correlated with calcium. Two-dimensional maps of Ti distribution show that the location of the element is characteristic for the route of administration and time of exposure. We demonstrated that µ-SRXRF can provide information on the distribution of titanium in internal structures of whole organs, which helps in enhancing our understanding of the mechanism of ionic titanium accumulation in the body. This is significant due to the popularity of titanium implants and the potential release of metal ions from them to the organism.

Grafting strategy to develop single site titanium on an amorphous silica surface.

PubMed

Capel-Sanchez, M C; Blanco-Brieva, G; Campos-Martin, J M; de Frutos, M P; Wen, W; Rodriguez, J A; Fierro, J L G

2009-06-16

Titanium/silica systems were prepared by grafting a titanium alkoxide (titanium isopropoxide and titanium (triethanolaminate) isopropoxide) precursor onto amorphous silica. The grafting process, which consisted of the hydrolysis of the Ti precursor by the hydroxyl groups on the silica surface, yielded samples containing Ti-loadings of 1-1.6 wt %. The as synthesized and calcined TiO(2)-SiO(2) samples were characterized by UV-vis, FTIR, XPS, and XANES spectroscopic techniques. These systems were tested in the liquid-phase epoxidation of oct-1-ene with hydrogen peroxide reaction. Spectroscopic data indicated that titanium anchoring takes place by reaction between the alkoxide precursor and surface OH groups of the silica substrate. The nature of surface titanium species generated by chemical grafting depends largely on the titanium precursor employed. Thus, the titanium isopropoxide precursor yields tetrahedrally coordinated polymeric titanium species, which give rise to a low-efficiency catalyst. However, if an atrane precursor (titanium (triethanolaminate) isopropoxide) is employed, isolated titanium species are obtained. The fact that these species remain isolated even after calcination is due to the protective effect of the triethanolaminate ligand that avoids titanium polymerization. These differences in the titanium environment have a pivotal role in the performance of these systems in the epoxidation of alkenes with hydrogen peroxide.

Electrochemical anodizing treatment to enhance localized corrosion resistance of pure titanium.

PubMed

Prando, Davide; Brenna, Andrea; Bolzoni, Fabio M; Diamanti, Maria V; Pedeferri, Mariapia; Ormellese, Marco

2017-01-26

Titanium has outstanding corrosion resistance due to the thin protective oxide layer that is formed on its surface. Nevertheless, in harsh and severe environments, pure titanium may suffer localized corrosion. In those conditions, costly titanium alloys containing palladium, nickel and molybdenum are used. This purpose investigated how it is possible to control corrosion, at lower cost, by electrochemical surface treatment on pure titanium, increasing the thickness of the natural oxide layer. Anodic oxidation was performed on titanium by immersion in H2SO4 solution and applying voltages ranging from 10 to 80 V. Different anodic current densities were considered. Potentiodynamic tests in chloride- and fluoride-containing solutions were carried out on anodized titanium to determine the pitting potential. All tested anodizing treatments increased corrosion resistance of pure titanium, but never reached the performance of titanium alloys. The best corrosion behavior was obtained on titanium anodized at voltages lower than 40 V at 20 mA/cm2. Titanium samples anodized at low cell voltage were seen to give high corrosion resistance in chloride- and fluoride-containing solutions. Electrolyte bath and anodic current density have little effect on the corrosion behavior.

Formation of low resistivity titanium silicide gates in semiconductor integrated circuits

DOEpatents

Ishida, Emi [Sunnyvale, CA

1999-08-10

A method of forming a titanium silicide (69) includes the steps of forming a transistor having a source region (58), a drain region (60) and a gate structure (56) and forming a titanium layer (66) over the transistor. A first anneal is performed with a laser anneal at an energy level that causes the titanium layer (66) to react with the gate structure (56) to form a high resistivity titanium silicide phase (68) having substantially small grain sizes. The unreacted portions of the titanium layer (66) are removed and a second anneal is performed, thereby causing the high resistivity titanium silicide phase (68) to convert to a low resistivity titanium silicide phase (69). The small grain sizes obtained by the first anneal allow low resistivity titanium silicide phase (69) to be achieved at device geometries less than about 0.25 micron.

21 CFR 73.3126 - Titanium dioxide.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Titanium dioxide. 73.3126 Section 73.3126 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR... specifications. The color additive titanium dioxide (CAS Reg. No. 13463-67-7), Color Index No. 77891, shall...

21 CFR 73.3126 - Titanium dioxide.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Titanium dioxide. 73.3126 Section 73.3126 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR... specifications. The color additive titanium dioxide (CAS Reg. No. 13463-67-7), Color Index No. 77891, shall...

21 CFR 73.3126 - Titanium dioxide.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Titanium dioxide. 73.3126 Section 73.3126 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR... specifications. The color additive titanium dioxide (CAS Reg. No. 13463-67-7), Color Index No. 77891, shall...

21 CFR 73.3126 - Titanium dioxide.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Titanium dioxide. 73.3126 Section 73.3126 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR... specifications. The color additive titanium dioxide (CAS Reg. No. 13463-67-7), Color Index No. 77891, shall...

21 CFR 73.3126 - Titanium dioxide.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Titanium dioxide. 73.3126 Section 73.3126 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR... specifications. The color additive titanium dioxide (CAS Reg. No. 13463-67-7), Color Index No. 77891, shall...

Characterization and morphology of prepared titanium dioxide nanofibers by electrospinning.

PubMed

Park, Ju-Young; Lee, In-Hwa

2010-05-01

Dispersed titanium dioxide in polymer nanofibers were prepared by sol-gel processing and electrospinning techniques using titanium isopropoxide (TiP)/polyvinylpyrrolidone (PVP) solution. The prepared titanium dioxide nanofibers were characterized by FE-SEM, TEM, XRD, and FT-IR. Pure titanium dioxide nanofibers were obtained from calcination of inorganic-organic composite fiber. The diameter of titanium oxide nanofibers were in the range of 70 nm to 150 nm. Prepared titanium dioxide nanofibers show rough surface and rather small diameter compare with TiP/PVP composite nanofibers. After calcined at 500 degrees C, TiO2 nanofibers convert into anatase and rutile mixed phased from amorphous structure. Calcination of these composite fibers above 600 degrees C resulted in pure rutile TiO2 nanofibers.

21 CFR 73.575 - Titanium dioxide.