Sample records for 17-7 ph stainless

  1. Axial-Load Fatigue Tests on 17-7 PH Stainless Steel Under Constant-Amplitude Loading

    NASA Technical Reports Server (NTRS)

    Leybold, Herbert A.

    1960-01-01

    Axial-load fatigue tests were conducted at room temperature on notched and unnotched sheet specimens of 17-7 PH stainless steel in Condition TH 1050. The notched specimens had theoretical stress-concentration factors of 2.32, 4.00, and 5.00. All specimens were tested under completely reversed loading. S-N curves are presented for each specimen configuration and ratios of fatigue strengths of unnotched specimens to those of notched specimens are given. Predictions of the fatigue behavior of notched specimens near the fatigue limit were made.

  2. Tensile Properties of 17-7 PH and 12 MoV Stainless-Steel Sheet under Rapid-Heating and Constant-Temperature Conditions

    NASA Technical Reports Server (NTRS)

    Manning, Charles R., Jr.; Price, Howard L.

    1961-01-01

    Results are presented of rapid-heating tests of 17-7 PH and 12 MoV stainless-steel sheet heated to failure at temperature rates from about 1 F to 170 F per second under constant-load conditions. Yield and rupture strengths obtained from rapid-heating tests are compared with yield and tensile strengths obtained from short-time elevated-temperature tensile tests (30-minute exposure). A rate-temperature parameter was used to construct master curves from which yield and rupture stresses or temperatures can be predicted. A method for measuring strain by optical means is described.

  3. Stress-Corrosion Cracking in Martensitic PH Stainless Steels

    NASA Technical Reports Server (NTRS)

    Humphries, T.; Nelson, E.

    1984-01-01

    Precipitation-hardening alloys evaluated in marine environment tests. Report describes marine-environment stress-corrosion cracking (SCC) tests of three martensitic precipitation hardening (PH) stainless-steel alloys.

  4. A scanning tunneling microscopy study of PH 3 adsorption on Si(1 1 1)-7 × 7 surfaces, P-segregation and thermal desorption

    NASA Astrophysics Data System (ADS)

    Ji, Jeong-Young; Shen, T.-C.

    2007-04-01

    PH 3 adsorption on Si(1 1 1)-7 × 7 was studied after various exposures between 0.3 and 60 L at room temperature by means of scanning tunneling microscopy (STM). PH 3-, PH 2-, H-reacted, and unreacted adatoms can be identified by analyzing empty-state STM images at different sample biases. PH x-reacted rest-atoms can be observed in empty-state STM images if neighboring adatoms are hydrogen terminated. Most of the PH 3 adsorbs dissociatively on the surface, generating H- and PH 2-adsorbed rest-atom and adatom sites. Dangling-bonds at rest-atom sites are more reactive than adatom sites and the faulted half of the 7 × 7 unit cell is more reactive than the unfaulted half. Center adatoms are overwhelmingly preferred over corner adatoms for PH 2 adsorption. The saturation P coverage is ˜0.18 ML. Annealing of PH 3-reacted 7 × 7 surfaces at 900 K generates disordered, partially P-covered surfaces, but dosing PH 3 at 900 K forms P/Si(1 1 1)- 6?{3} surfaces. Si deposition at 510 K leaves disordered clusters on the surface, which cannot be reordered by annealing up to 800 K. However, annealing above 900 K recreates P/Si(1 1 1)- 6?{3} surfaces. Surface morphologies formed by sequential rapid thermal annealing are also presented.

  5. High temperature tensile behavior of a PH stainless steel

    Microsoft Academic Search

    M. Aghaie-Khafri; A. Zargaran

    2010-01-01

    High temperature tensile deformation of 15-5 PH stainless steel in peak age and overaged conditions has been studied over the temperature range of 300 to 600°C and different strain rates. Dynamic recrystallization was the main softening mechanism when the alloy deformed at imposed temperature and strain rate region. The apparent activation energy was calculated as 284.8 and 323.1kJ\\/mol for peak

  6. Hot deformation of 15-5 PH stainless steel

    Microsoft Academic Search

    M. Aghaie-Khafri; F. Adhami

    2010-01-01

    The hot deformation behavior of 15-5 PH stainless steel has been studied using hot compression tests over the temperature range of 900–1150°C and strain rates varying between 0.001 and 0.5s?1. The results showed that dynamic recrystallization is the main softening mechanism when the alloy deformed at imposed temperature and strain rate region. Strain rate sensitivity of the material was evaluated

  7. Biocompatibility of 17-4 PH stainless steel foam for implant applications.

    PubMed

    Mutlu, Ilven; Oktay, Enver

    2011-01-01

    In this study, biocompatibility of 17-4 PH stainless steel foam for biomedical implant applications was investigated. 17-4 PH stainless steel foams having porosities in the range of 40-82% with an average pore size of around 600 ?m were produced by space holder-sintering technique. Sintered foams were precipitation hardened for times of 1-6 h at temperatures between 450-570 °C. Compressive yield strength and Young's modulus of aged stainless steel foams were observed to vary between 80-130 MPa and 0.73-1.54 GPa, respectively. Pore morphology, pore size and the mechanical properties of the 17-4 PH stainless steel foams were close to cancellous bone. In vitro evaluations of cytotoxicity of the foams were investigated by XTT and MTT assays and showed sufficient biocompatibility. Surface roughness parameters of the stainless steel foams were also determined to characterize the foams. PMID:22182790

  8. Corrosion of 15-5PH H1025 stainless steel due to environmental conditions

    Microsoft Academic Search

    A. Abad; M. Hahn; O. S. Es-Said

    2010-01-01

    A simple corrosion experiment was conducted to simulate the effects of stray current and salt water environmental conditions of 15-5PH H1025 stainless steel, which is a common material used on aircraft. Pieces of non-corroded 15-5PH H1025 stainless steel were immersed in 71°C tap water without current, 71°C tap water with current, and deionized water with current. It was determined that

  9. Hybrid Laser-arc Welding of 17-4 PH Martensitic Stainless Steel

    NASA Astrophysics Data System (ADS)

    Liu, Wei; Ma, Junjie; Atabaki, Mehdi Mazar; Pillai, Raju; Kumar, Biju; Vasudevan, Unnikrishnan; Sreshta, Harold; Kovacevic, Radovan

    2015-06-01

    17-4 PH stainless steel has wide applications in severe working conditions due to its combination of good corrosion resistance and high strength. The weldability of 17-4 PH stainless steel is challenging. In this work, hybrid laser-arc welding was developed to weld 17-4 PH stainless steel. This method was chosen based on its advantages, such as deep weld penetration, less filler materials, and high welding speed. The 17-4 PH stainless steel plates with a thickness of 19 mm were successfully welded in a single pass. During the hybrid welding, the 17-4 PH stainless steel was immensely susceptible to porosity and solidification cracking. The porosity was avoided by using nitrogen as the shielding gas. The nitrogen stabilized the keyhole and inhibited the formation of bubbles during welding. Solidification cracking easily occurred along the weld centerline at the root of the hybrid laser-arc welds. The microstructural evolution and the cracking susceptibility of 17-4 PH stainless steel were investigated to remove these centerline cracks. The results showed that the solidification mode of the material changed due to high cooling rate at the root of the weld. The rapid cooling rate caused the transformation from ferrite to austenite during the solidification stage. The solidification cracking was likely formed as a result of this cracking-susceptible microstructure and a high depth/width ratio that led to a high tensile stress concentration. Furthermore, the solidification cracking was prevented by preheating the base metal. It was found that the preheating slowed the cooling rate at the root of the weld, and the ferrite-to-austenite transformation during the solidification stage was suppressed. Delta ferrite formation was observed in the weld bead as well no solidification cracking occurred by optimizing the preheating temperature.

  10. Failure of a 17-4 PH stainless steel sailboat propeller shaft

    Microsoft Academic Search

    C. Fahir Arisoy; Gokhan Ba?man; M. Kelami ?e?en

    2003-01-01

    In this study, a 17-4 PH precipitation hardening stainless steel propeller shaft failed in use when installed in a sailboat working in a marine environment. Failure analysis was conducted on the propeller shaft. Results indicate that the failure was caused by the fracture of the propeller shaft by torsional fatigue and stress corrosion cracking (SCC). SCC progressed transgranulary in the

  11. Compressive Strength of Stainless-Steel Sandwiches at Elevated Temperatures

    NASA Technical Reports Server (NTRS)

    Mathauser, Eldon E.; Pride, Richard A.

    1959-01-01

    Experimental results are presented from crippling tests of stainless-steel sandwich specimens in the temperature range from 80 F to 1,200 F. The specimens included resistance-welded 17-7 PH stainless-steel sandwiches with single-corrugated cores, type 301 stainless-steel sandwiches with double-corrugated cores, and brazed 17-7 PH stainless-steel sandwiches with honeycomb cores. The experimental strengths are compared with predicted buckling and crippling strengths. The crippling strengths were predicted from the calculated maximum strength of the individual plate elements of the sandwiches and from a correlation procedure which gives the elevated-temperature crippling strength when the experimental room-temperature crippling strengths are known. Photographs of some of the tested specimens are included to show the modes of failure.

  12. Failure analysis of a set of stainless steel disc springs

    Microsoft Academic Search

    G. Atxaga; A. Pelayo; A. M. Irisarri

    2006-01-01

    This paper analyses the failure of a set of disc springs, broken in service in a seawater environment and at high temperature. These components were manufactured using a 17-7 PH, UNS S17700 precipitation hardening stainless steel. The morphology of the cracks was intergranular and it was attributed to hydrogen embrittlement due to the hydrogen that entered into the steel during

  13. The strength, fracture toughness, and low cycle fatigue behavior of 17-4 PH stainless steel

    Microsoft Academic Search

    H. J. Rack; David Kalish

    1974-01-01

    The influence of microstructure on the strength, fracture toughness and low cycle fatigue behavior of 17-4 PH stainless steel\\u000a has been examined. Aging hardening involves initial formation of coherent copper-rich clusters which transform to incoherent\\u000a fee ?-copper precipitates upon further aging. The changes in strength level and strain hardening rates observed during aging\\u000a are consistent with previously suggested models for

  14. High-temperature fatigue crack growth behavior of 17-4 PH stainless steels

    Microsoft Academic Search

    Kuei-Chang Hsu; Chih-Kuang Lin

    2004-01-01

    The fatigue crack growth (FCG) behavior was investigated for 17-4 PH stainless steels in three heat-treated conditions, i.e., unaged (condition A), peak-aged (condition H900), and overaged (condition H1150), at temperatures ranging from 300 C to\\u000a 500 C. The high-temperature fatigue crack growth rates (FCGRs) of condition H1150 were increased with an increase in temperature.\\u000a However, for conditions A and H900

  15. Embrittlement of laser surface-annealed 17-4 PH stainless steel

    Microsoft Academic Search

    L. W Tsay; T. Y Yang; M. C Young

    2001-01-01

    Stress corrosion cracking and fatigue crack growth behavior were determined in 17-4 PH stainless steel under various metallurgical conditions, including the H900 (482°C\\/1 h), H1025 (552°C\\/4 h) aging and laser surface annealing treatments. Peak-aged (H900) specimens locally irradiated by laser beam consisted of a portion of composite region (CR), in which comprised of soft laser-annealed (LA) zones on the outer

  16. Tensile and fatigue properties of 17-4 PH stainless steel at high temperatures

    Microsoft Academic Search

    Jui-Hung Wu; Chih-Kuang Lin

    2002-01-01

    The tensile and high-cycle fatigue properties for 17-4 PH* stainless steels in three different conditions were investigated\\u000a at temperatures ranging from room temperature to 400 C. Results indicated that the yield strength and fatigue strength for\\u000a the three conditions at a given temperature took the following order: condition H900 > condition A> condition H1150. The yield\\u000a strength of each condition

  17. Effects of ion implantation on friction and wear of stainless steels. [15-5PH

    Microsoft Academic Search

    L. E. Pope; F. G. Yost; D. M. Follstaedt; J. A. Knapp; S. T. Picraux

    1982-01-01

    Friction and wear of 304, 15-5 PH and 440C stainless steels and of pure Fe are shown to be reduced by ion implantation of Ti and C. Mechanically polished samples were ion implanted to fluences of 2 x 10¹⁵ Ti\\/mm² (90 to 180 keV) and 2 x 10¹⁵ C\\/mm² (30 keV); the implantation profiles of the two elements extended to

  18. Hot-cracking mechanism in COâ laser beam welds of dissimilar metals involving PH martensitic stainless steels

    Microsoft Academic Search

    Cieslak

    1987-01-01

    Autogenous COâ laser beam welds were made between Alloy HP 9-4-20 and both 15-5 PH and PH 13-8 Mo stainless steel. Small scale circular-patch test specimens revealed that the combination involving the Nb-bearing alloy, 15-5 PH, was far more crack susceptible than the combination involving the Nb-free alloy, PH 13-8 Mo. Analytical electron microscopy was used to identify an NbC\\/austenite

  19. Properties of cryogenically worked metals. [stainless steels

    NASA Technical Reports Server (NTRS)

    Schwartzberg, F. R.; Kiefer, T. F.

    1975-01-01

    A program was conducted to determine whether the mechanical properties of cryogenically worked 17-7PH stainless steel are suitable for service from ambient to cryogenic temperatures. It was determined that the stress corrosion resistance of the cryo-worked material is quite adequate for structural service. The tensile properties and fracture toughness at room temperature were comparable to titanium alloy 6Al-4V. However, at cryogenic temperatures, the properties were not sufficient to recommend consideration for structural service.

  20. Stress corrosion cracking behaviour of precipitation hardened stainless steels in high purity water environments

    Microsoft Academic Search

    C. Gaona-Tiburcio; F. Almeraya-Calderón; A. Martínez-Villafañe; R. Bautista-Margulis

    2001-01-01

    The susceptibility of 17-4PH and 17-7PH stainless steels to stress corrosion cracking (SCC) is examined in the present investigation. The specimens were tested in the presence of NaCl and NaOH (20%) at 908C and various pH values. The evaluations were carried out using the CERT test, at a speed of 10-6s-1, supplemented by anodic polarisation and electrochemical noise analysis. The

  1. Flow Curve Analysis of 17-4 PH Stainless Steel under Hot Compression Test

    NASA Astrophysics Data System (ADS)

    Mirzadeh, Hamed; Najafizadeh, Abbas; Moazeny, Mohammad

    2009-12-01

    The hot compression behavior of a 17-4 PH stainless steel (AISI 630) has been investigated at temperatures of 950 °C to 1150 °C and strain rates of 10-3 to 10 s-1. Glass powder in the Rastegaev reservoirs of the specimen was used as a lubricant material. A step-by-step procedure for data analysis in the hot compression test was given. The work hardening rate analysis was performed to reveal if dynamic recrystallization (DRX) occurred. Many samples exhibited typical DRX stress-strain curves with a single peak stress followed by a gradual fall toward the steady-state stress. At low Zener-Hollomon ( Z) parameter, this material showed a new DRX flow behavior, which was called multiple transient steady state (MTSS). At high Z, as a result of adiabatic deformation heating, a drop in flow stress was observed. The general constitutive equations were used to determine the hot working constants of this material. Moreover, after a critical discussion, the deformation activation energy of 17-4 PH stainless steel was determined as 337 kJ/mol.

  2. Hot-cracking mechanism in CO/sub 2/ laser beam welds of dissimilar metals involving PH martensitic stainless steels

    SciTech Connect

    Cieslak, M.J.

    1987-02-01

    Autogenous CO/sub 2/ laser beam welds were made between Alloy HP 9-4-20 and both 15-5 PH and PH 13-8 Mo stainless steel. Small scale circular-patch test specimens revealed that the combination involving the Nb-bearing alloy, 15-5 PH, was far more crack susceptible than the combination involving the Nb-free alloy, PH 13-8 Mo. Analytical electron microscopy was used to identify an NbC/austenite eutectic-like constituent as being responsible for the cracking phenomenon.

  3. Post-irradiation characterization of PH13-8Mo martensitic stainless steel

    NASA Astrophysics Data System (ADS)

    Jong, M.; Schmalz, F.; Rensman, J. W.; Luzginova, N. V.; Wouters, O.; Hegeman, J. B. J.; van der Laan, J. G.

    2011-10-01

    The irradiation response of PH13-8Mo stainless steel was measured up to 2.5 dpa at 200 and 300 °C irradiation temperatures. The PH13-8Mo, a martensitic precipitation-hardened steel, was produced by Hot Isostatic Pressing at 1030 °C. The fatigue tests (high cycle fatigue and fatigue crack propagation) showed a test temperature dependency but no irradiation effects. Tensile tests showed irradiation hardening (yield stress increase) of approximately 37% for 200 °C irradiated material tested at 60 °C and approximately 32% for 300 °C irradiated material tested at 60 °C. This contradicts the shift in reference temperature ( T0) measured in toughness tests (Master Curve approach), where the ? T0 for 300 °C irradiated is approximately 170 °C and the ? T0 for the 200 °C irradiated is approximately 160 °C. This means that the irradiation hardening of PH13-8Mo steel is not suitable to predict the shift in the reference temperature for the Master Curve approach.

  4. Failure Maps for Rectangular 17-4PH Stainless Steel Sandwiched Foam Panels

    NASA Technical Reports Server (NTRS)

    Raj, S. V.; Ghosn, L. J.

    2007-01-01

    A new and innovative concept is proposed for designing lightweight fan blades for aircraft engines using commercially available 17-4PH precipitation hardened stainless steel. Rotating fan blades in aircraft engines experience a complex loading state consisting of combinations of centrifugal, distributed pressure and torsional loads. Theoretical failure plastic collapse maps, showing plots of the foam relative density versus face sheet thickness, t, normalized by the fan blade span length, L, have been generated for rectangular 17-4PH sandwiched foam panels under these three loading modes assuming three failure plastic collapse modes. These maps show that the 17-4PH sandwiched foam panels can fail by either the yielding of the face sheets, yielding of the foam core or wrinkling of the face sheets depending on foam relative density, the magnitude of t/L and the loading mode. The design envelop of a generic fan blade is superimposed on the maps to provide valuable insights on the probable failure modes in a sandwiched foam fan blade.

  5. Mechanical Properties of 17-4PH Stainless Steel Foam Panels

    NASA Technical Reports Server (NTRS)

    Raj, S. V.; Ghosn, L. J.; Lerch, B. a.; Hebsur, M.; Cosgriff, L. M.; Fedor, J.

    2007-01-01

    Rectangular 17-4PH stainless steel sandwiched foam panels were fabricated using a commercial manufacturing technique by brazing two sheets to a foam core. Microstructural observations and ultrasonic nondestructive evaluation of the panels revealed large variations in the quality of the brazed areas from one panel to the next as well as within the same panel. Shear tests conducted on specimens machined from the panels exhibited failures either in the brazed region or in the foam core for the poorly brazed and well-brazed samples, respectively. Compression tests were conducted on the foam cores to evaluate their elastic and plastic deformation behavior. These data were compared with published data on polymeric and metallic foams, and with theoretical deformation models proposed for open cell foams.

  6. LOW PLASTICITY BURNISHING (LPB) TREATMENT TO MITIGATE FOD AND CORROSION FATIGUE DAMAGE IN 17-4 PH STAINLESS STEEL

    Microsoft Academic Search

    Paul S. Prevéy; N. Jayaraman

    The benefits of applying low plasticity burnishing (LPB) to 17-4PH Stainless Steel (H1100) on both the fatigue and corrosion fatigue performance were compared with the shot peened (SP) and low stress ground (LSG) conditions. LPB treatment dramatically improved both the high cycle fatigue (HCF) performance and fatigue strength. The baseline LSG and SP treatments showed similar fatigue strengths of about

  7. Mitigation of FOD and Corrosion Fatigue Damage in 17-4 PH Stainless Steel Compressor Blades with Surface Treatment

    Microsoft Academic Search

    Paul S. Prevéy; N. Jayaraman; Ravi Ravindranath

    Compressor blades of a military aircraft turbine engine made of 17 -4 PH stainless steel have been reported to have blade edge foreign object damage (FOD), corrosion pitting, and erosion damage that reduce fatigue life. This paper reports the findings of a comprehensive investigation of the effect of residual compressive stresses, imparted by various surface treatments, to improve leading edge

  8. Influence of heat treatment on hysteresis error of force transducers manufactured from 17-4PH stainless steel

    Microsoft Academic Search

    Bulent Aydemir; Erdinc Kaluc; Sinan Fank

    2006-01-01

    Different heat treatment processes can be applied on the spring element of a force transducer in order to obtain good and satisfactory performance. The study covers the attempts of different heat treatments on spring element using 17-4PH precipitation hardened stainless steel, which is regarded as one of the best and popular spring materials for force sensor applications. Heat treatments named

  9. Effect of implantation species on the tribological response of stainless steel surfaces. [SS15-5PH

    Microsoft Academic Search

    L. E. Pope; S. T. Picraux; D. M. Follstaedt; J. A. Knapp; F. G. Yost

    1984-01-01

    The friction and wear properties of 304 and 15-5 PH stainless steels which were ion implanted with P and with P plus C have been examined and are compared with the properties of the same steels implanted with N and with Ti plus C. While benefits are obtained with the P and the P plus C implantation treatments, the N

  10. On the correlation between fracture toughness and precipitation hardening heat treatments in 15-5PH Stainless Steel

    Microsoft Academic Search

    M. Abdelshehid; K. Mahmodieh; K. Mori; L. Chen; P. Stoyanov; D. Davlantes; J. Foyos; J. Ogren; R CLARKJR; O. S. Es-Said

    2007-01-01

    In this study, the fracture toughness, Kq, and the yield strength of precipitation heat-treated Stainless Steel 15-5 PH was determined. Thirty six cylindrical tensile bars and eighteen compact tension C(T) specimens were tested. It was found that the high tolerance for solution heat treatment decreases the Kq value significantly, while the yield strength remains virtually unaltered.

  11. Alloy Shrinkage factors for the investment casting of 17-4PH stainless steel parts

    SciTech Connect

    Sabau, Adrian S [ORNL; Porter, Wallace D [ORNL

    2008-01-01

    In this study, the alloy shrinkage factors were obtained for the investment casting of 17-4PH stainless steel parts. For the investment casting process, unfilled wax and fused silica with a zircon prime coat were used for patterns and shell molds, respectively. Dimensions of the die tooling, wax pattern, and casting were measured using a Coordinate Measurement Machine. For all the properties, the experimental data available in the literature did not cover the entire temperature range necessary for process simulation. A comparison between the predicted material property data measured property data is made. It was found that most material properties were accurately predicted over the most of the temperature range of the process. Several assumptions were made in order to obtain a complete set of mechanical property data at high temperatures. Thermal expansion measurements for the 17-4PH alloy were conducted at heating and cooling. As a function of temperature, the thermal expansion for both the alloy and shell mold materials showed different evolution at heating and cooling. Thus, one generic simulation were performed with thermal expansion obtained at heating and another one with thermal expansion obtained at cooling. The alloy dimensions were obtained from numerical simulation results of solidification, heat transfer, and deformation phenomena. As compared with experimental results, the numerical simulation results for the shrinkage factors were slightly over-predicted.

  12. Effects of ion implantation on friction and wear of stainless steels. [15-5PH

    SciTech Connect

    Pope, L.E.; Yost, F.G.; Follstaedt, D.M.; Knapp, J.A.; Picraux, S.T.

    1982-01-01

    Friction and wear of 304, 15-5 PH and 440C stainless steels and of pure Fe are shown to be reduced by ion implantation of Ti and C. Mechanically polished samples were ion implanted to fluences of 2 x 10/sup 15/ Ti/mm/sup 2/ (90 to 180 keV) and 2 x 10/sup 15/ C/mm/sup 2/ (30 keV); the implantation profiles of the two elements extended to approx. 0.1 ..mu..m and approximately overlapped each other. The effects of normal load (Hertzian stresses in the range of 690 to 1840 MPa) on friction and wear were evaluated in the pin-on-disc configuration with no lubrication. 304 pins were used and are shown to give results similar to those previously reported for 440C pins. Ion implantation reduces friction coefficients by up to 80% and decreases the maximum wear depths by up to 95%, but the magnitude of reductions depends on the material and the load conditions. Transfer of material containing Ti from the implanted plates to both 304 and 440C pins was observed. A change in wear mechanism was detected in the wear tracks as the load was increased: fine-scale abrasive-type parallel grooves were present at light loads while galling was observed at high loads. 6 figures.

  13. Microstructural evolution in a 17-4 PH stainless steel after aging at 400 °C

    NASA Astrophysics Data System (ADS)

    Murayama, M.; Hono, K.; Katayama, Y.

    1999-02-01

    The microstructure of 17-4 PH stainless steel at various stages of heat treatment, i.e., after solution heat treatment, tempering at 580 °C, and long-term aging at 400 °C, have been studied by atom probe field ion microscopy (APFIM) and transmission electron microscopy (TEM). The solution-treated specimen consists largely of martensite with a small fraction of ?-ferrite. No precipitates are present in the martensite phase, while spherical fcc-Cu particles are present in the ?-ferrite. After tempering for 4 hours at 580 °C, coherent Cu particles precipitate in the martensite phase. At this stage, the Cr concentration in the martensite phase is still uniform. After 5000 hours aging at 400 °C, the martensite spinodaly decomposes into Fe-rich ? and Cr-enriched ??. In addition, fine particles of the G-phase (structure type D8 a , space group Fmbar 3m) enriched in Si, Ni, and Mn have been found in intimate contact with the Cu precipitates. Following spinodal decomposition of the martensite phase, G-phase precipitation occurs after long-term aging.

  14. Effect of strain rate on high-temperature low-cycle fatigue of 17-4 PH stainless steels

    Microsoft Academic Search

    Jui-Hung Wu; Chih-Kuang Lin

    2005-01-01

    The effect of strain rate (10?2, 10?3 and 10?4s?1) on the low-cycle fatigue (LCF) behavior was investigated for 17-4 PH stainless steels in three different conditions at temperatures of 300–500°C. The cyclic stress response (CSR) for Condition A tested at 300 and 400°C showed cyclic hardening due to an influence of dynamic strain aging (DSA). An in situ precipitation-hardening effect

  15. Role of electro-discharge machining on the fatigue performance of 15–5PH stainless steel component

    Microsoft Academic Search

    Abhay K. Jha; K. Sreekumar; P. P. Sinha

    2010-01-01

    Precipitation hardened stainless steel of 15–5PH grade is used for fabrication of actuator components. During one of the qualification tests, a piston made of this steel was fractured under cyclic loading. Analysis revealed that fracture initiated at the electro-discharge machined surface and propagated under cyclic loading.Efforts were made to establish role of various parameters of electro-discharge machining to the fatigue

  16. Water Droplet Erosion Behavior of High-Power Diode Laser Treated 17Cr4Ni PH Stainless Steel

    NASA Astrophysics Data System (ADS)

    Mann, B. S.

    2014-05-01

    This article deals with water droplet erosion (WDE) behavior of high-power diode laser (HPDL) treated 17Cr4Ni PH stainless steel. After HPDL treatment, the water droplet erosion resistance (WDER) of 17Cr4Ni PH stainless steel has not improved. The main reason is the surface hardness, which has not improved after HPDL treatment though the microstructure has become much finer. On the other hand, precipitation hardening of the alloy at 490°C for 3 h has resulted in improved WDER more than twice. This is because of its increased microhardness and improved modified ultimate resilience (MUR), and formation of fine grained microstructure. The WDER has been correlated with MUR, a single mechanical property, based upon microhardness, ultimate tensile strength, and Young's modulus. WDERs of HPDL treated, untreated, and precipitation hardened 17Cr4Ni PH stainless steel samples were determined using a WDE test facility as per ASTM G73-1978. The WDE damage mechanism, compared on the basis of MUR and scanning electron micrographs, is discussed and reported in this article.

  17. Influence of pH on the passivation behavior of 254SMO stainless steel in 3.5% NaCl solution

    Microsoft Academic Search

    C. T. Liu; J. K. Wu

    2007-01-01

    The potentiodynamic polarization measurement of 254SMO stainless steel (UNS 31254) was conducted in 3.5% NaCl solutions with pH ranging from 0.1 to 5. The results indicated that this stainless steel offered excellent pitting corrosion resistance in corrosive environments. Further, it also exhibited various features on the polarization curves in different pH solutions. The electrochemical constant-potential passivation treatment performed at different

  18. Effects of Temperature on Microstructure and Wear of Salt Bath Nitrided 17-4PH Stainless Steel

    NASA Astrophysics Data System (ADS)

    Wang, Jun; Lin, Yuanhua; Fan, Hongyuan; Zeng, Dezhi; Peng, Qian; Shen, Baoluo

    2012-08-01

    Salt bath nitriding of 17-4 PH martensitic precipitation hardening stainless steels was conducted at 610, 630, and 650 °C for 2 h using a complex salt bath heat-treatment, and the properties of the nitrided surface were systematically evaluated. Experimental results revealed that the microstructure and phase constituents of the nitrided surface alloy are highly process condition dependent. When 17-4PH stainless steel was subjected to complex salt bathing nitriding, the main phase of the nitrided layer was expanded martensite (?'), expanded austenite (?N), CrN, Fe4N, and (Fe,Cr) x O y . In the sample nitrided above 610 °C, the expanded martensite transformed into expanded austenite. But in the sample nitrided at 650 °C, the expanded austenite decomposed into ?N and CrN. The decomposed ?N then disassembled into CrN and alpha again. The nitrided layer depth thickened intensively with the increasing nitriding temperature. The activation energy of nitriding in this salt bath was 125 ± 5 kJ/mol.

  19. Effect of implantation species on the tribological response of stainless steel surfaces. [SS-15-5PH

    SciTech Connect

    Pope, L.E.; Picraux, S.T.; Follstaedt, D.M.; Knapp, J.A.; Yost, F.G.

    1984-01-01

    The friction and wear properties of 304 and 15-5 PH stainless steels which were ion implanted with P and with P plus C have been examined and are compared with the properties of the same steels implanted with N and with Ti plus C. While benefits are obtained with the P and the P plus C implantation treatments, the N and the Ti plus C treatments give greater reductions in wear which extend to more severe wear regimes; with Ti plus C, friction is also reduced. Transmission electron microscopy shows that the P and the P plus C implantations (with 20 to 30 at. % metalloid concentrations) produce surface alloys with amorphous phases, as do Ti plus C treatments (approximately 20 at. % each). The greater benefits obtained with the Ti plus C amorphous phase imply that this phase is mechanically superior to the amorphous phase with P plus C, even though the latter has been shown to have excellent mechanical properties when produced by melt quenching. Ti and C were selected for implantation into a 15-5 PH discriminator wheel of an electromechanical device for comparison with standard solid film lubrication (MoS/sub 2/). In comparison to a solid film lubricated wheel, the implanted wheel (unlubricated) performed equally well with respect to time of operation, number of cycles and tolerance control; in addition the implanted wheel produced less debris. An alternate ion beam method was used to add high surface concentrations to control fretting corrosion and debris generation of a journal bearing in a different electromechanical device: a sputter-deposited Au film (50 nm) on 15-5 PH stainless steel was ion bombarded with 300 keV Xe/sup +/. This treated surface was compared with a sputtered Au film without ion beam treatment, with electrodeposited Au and with a solid lubricating film. The ion mixed Au surface bearings had the least corrosion and debris.

  20. 45 CFR 17.7 - Retractions or corrections.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...17.7 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION RELEASE OF ADVERSE INFORMATION TO NEWS MEDIA § 17.7 Retractions or corrections. Where the Assistant Secretary for Public Affairs finds that information...

  1. 45 CFR 17.7 - Retractions or corrections.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...17.7 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION RELEASE OF ADVERSE INFORMATION TO NEWS MEDIA § 17.7 Retractions or corrections. Where the Assistant Secretary for Public Affairs finds that information...

  2. 45 CFR 17.7 - Retractions or corrections.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...17.7 Public Welfare Department of Health and Human Services GENERAL ADMINISTRATION RELEASE OF ADVERSE INFORMATION TO NEWS MEDIA § 17.7 Retractions or corrections. Where the Assistant Secretary for Public Affairs finds that information...

  3. A pH Sensor Based on a Stainless Steel Electrode Electrodeposited with Iridium Oxide

    ERIC Educational Resources Information Center

    Martinez, C. C. M.; Madrid, R. E.; Felice, C. J.

    2009-01-01

    A simple procedure to make an iridium oxide (IrO[subscript 2]) electrodeposited pH sensor, that can be used in a chemical, biomedical, or materials laboratory, is presented here. Some exercises, based on this sensor, that can be used to teach important concepts in the field of biomedical, biochemical, tissue, or materials engineering, are also…

  4. Role of alloy additions on strengthening in 17-4 PH stainless steel

    NASA Astrophysics Data System (ADS)

    Murthy, Arpana Sudershan

    Alloy modifications by addition of niobium (Nb), vanadium (V), nitrogen (N) and cobalt (Co) to cast 17-4 PH steel were investigated to determine the effect on mechanical properties. Additions of Nb, V, and N increased the yield strength from 1120 MPa to 1310 MPa while decreased the room temperature charpy V notch (CVN) toughness from 20 J to four Joules. The addition of Co to cast 17-4 PH steel enhanced the yield strength and CVN toughness from 1140 MPa to 1290 MPa and from 3.7 J to 5.5 J, respectively. In the base 17-4 PH steel, an increase in block width from 2.27 ± 0.10 ?m in the solution treated condition to 3.06 ± 0.17 ?m upon aging at 755 K was measured using orientation image microscopy. Cobalt inhibited recrystallization and block boundary migration during aging resulting in a finer martensitic block structure. The influence of Co on copper (Cu) precipitation in steels was studied using atom probe tomography. A narrower precipitate size distribution was observed in the steels with Co addition. The concentration profile across the matrix / precipitate interface indicated rejection of Co atoms from the copper precipitates. This behavior was observed to be energetically favorable using first principle calculations. The activation energies for Cu precipitation increased from 205 kJ/ mol in the non-cobalt containing alloy, to 243 kJ/ mol, and 272 kJ/ mol in alloys with 3 wt. %Co, and 7 wt. % Co, respectively. The role of Co on Cu precipitation in cast 17-4 PH steel is proposed as follows: (i) Co is rejected out of the Cu precipitate and sets up a barrier to the growth of the Cu precipitate; (ii) results in Cu precipitates of smaller size and narrower distribution; (iii) the coarsening of Cu precipitates is inhibited; and (iv) the activation energy for Cu precipitation increases.

  5. Constituted oxides/nitrides on nitriding 304, 430 and 17-4 PH stainless steel in salt baths over the temperature range 723 to 923 K

    NASA Astrophysics Data System (ADS)

    Shih, Teng-Shih; Huang, Yung-Sen; Chen, Chi-Fan

    2011-10-01

    The progressively developed oxides and nitrides that form on nitriding 304, 430 and 17-4 PH stainless steel are analysed by X-ray Diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS) in this study. The experimental results show that the Cr contents and matrix structures (ferrite, austenite and martensite) play an important role in forming FeCr 2O 4, Cr 2O 3 and Fe 2O 3 oxides as well as nitrides. After a short immersion time, oxides of Cr 2O 3 and FeCr 2O 4 form in nitride films on 304 stainless steel samples. Fe 2O 3 oxide will subsequently form following an increasing immersion time. For the 430 stainless steel, Cr 2O 3 predominately forms after a short dipping time which hinders the growth of the nitride layer. As a result, this sample had the thinnest nitride film of the three for a given immersion time. After the formation of oxides, both CrN and Cr 2N were detected near the surface of the nitride films of three samples while Cr 2N phases formed in the deeper zone. The greatest amount of Fe 2O 3 oxide among the three samples was obtained on the nitriding 17-4 PH stainless steel which also had a high intensity count of N 1s.

  6. Metallurgical Analysis of Crack Initiation of Wire-Cut Electrical Discharge-Machined Spline Actuators Made of 17-4 PH Stainless Steel

    Microsoft Academic Search

    Ahmad-Reza Etemadi; Bahram Fazel; Armin Emami

    Spline actuators made of investment cast 17-4 PH (precipitation hardening) stainless steel were found to contain micro-cracks.\\u000a The cracked actuators were subjected to optical and scanning electron microscopy and hardness testing, which revealed that\\u000a the failure occurred due to fatigue crack initiation and growth after electrical discharge machining (EDM). The rehardened\\u000a layer produced by the EDM remained after machining, and

  7. Microstructures of stainless steels exhibiting reduced friction and wear after implantation with Ti and C. [304; 15-5 PH; Nitronic 60; 440C

    Microsoft Academic Search

    D. M. Follstaedt; F. G. Yost; L. E. Pope

    1983-01-01

    Implantation of Ti and C into stainless steel discs of Types 304, 15-5 PH, Nitronic 60 and 440C has previously been reported to reduce wear depths by up to approx. 85% and friction by approx. 50% in unlubricated pin-on-disc tests. Our earlier studies relating microstructure to friction and wear results in Type 304 are first summarized: these indicate that the

  8. Nuclear microprobe analysis of wear tracks on ¹⁴N-implanted steels. [15-5 PH and 304 stainless steels

    Microsoft Academic Search

    B. L. Doyle; D. M. Follstaedt; S. T. Picraux; F. G. Yost; L. E. Pope; J. A. Knapp

    1984-01-01

    Two nuclear microbeam analysis techniques (3.7 MeV (..cap alpha..,p) and 6 MeV (..cap alpha..,..cap alpha..)) have been used to determine the local areal density of ¹⁴N which remains in wear tracks resulting from pin-on-disc testing of nitrogen implanted 15-5 PH and 304 stainless steels. The microbeam analysis shows that the extent of N migration into the 15-5 substrate was to

  9. Effect of passive film on mechanical properties of martensitic stainless steel 15-5PH in a neutral NaCl solution

    NASA Astrophysics Data System (ADS)

    Guo, Qiang; Liu, Jianhua; Yu, Mei; Li, Songmei

    2015-02-01

    The effect of passive film on mechanical properties of the martensitic stainless steel 15-5PH in neutral 3.5 wt% NaCl solution was investigated, using surface analysis techniques, electrochemical measurements and slow strain rate technique. In neutral 3.5 wt% NaCl solution, the passive film formed at passivity potential is mainly divided into iron oxides-rich outer layer (FeO, Fe2O3) and chromium oxides-rich inner layer (Cr2O3, Cr(OH)3). During crack propagation, the passive film reduced formation of micro-cracks and micro-cleavages around the crack tip, and as a consequence, remarkably increased the fracture ductility of the martensitic stainless steel.

  10. 43 CFR 17.7 - Procedure for effecting compliance.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...Interior NONDISCRIMINATION IN FEDERALLY ASSISTED PROGRAMS OF THE DEPARTMENT OF THE INTERIOR Nondiscrimination on the Basis of Race, Color, or National Origin § 17.7 Procedure for effecting compliance. (a) General. If there...

  11. 43 CFR 17.7 - Procedure for effecting compliance.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...Interior NONDISCRIMINATION IN FEDERALLY ASSISTED PROGRAMS OF THE DEPARTMENT OF THE INTERIOR Nondiscrimination on the Basis of Race, Color, or National Origin § 17.7 Procedure for effecting compliance. (a) General. If there...

  12. 43 CFR 17.7 - Procedure for effecting compliance.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Interior NONDISCRIMINATION IN FEDERALLY ASSISTED PROGRAMS OF THE DEPARTMENT OF THE INTERIOR Nondiscrimination on the Basis of Race, Color, or National Origin § 17.7 Procedure for effecting compliance. (a) General. If there...

  13. 43 CFR 17.7 - Procedure for effecting compliance.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...Interior NONDISCRIMINATION IN FEDERALLY ASSISTED PROGRAMS OF THE DEPARTMENT OF THE INTERIOR Nondiscrimination on the Basis of Race, Color, or National Origin § 17.7 Procedure for effecting compliance. (a) General. If there...

  14. 43 CFR 17.7 - Procedure for effecting compliance.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...Interior NONDISCRIMINATION IN FEDERALLY ASSISTED PROGRAMS OF THE DEPARTMENT OF THE INTERIOR Nondiscrimination on the Basis of Race, Color, or National Origin § 17.7 Procedure for effecting compliance. (a) General. If there...

  15. The effect of 17-4PH stainless steel on the lifetime of a Pennzane lubricated Microwave Limb Sounder Antenna Actuator Assembly ball screw for the AURA spacecraft

    NASA Astrophysics Data System (ADS)

    Jones, William R., Jr.; Jansen, Mark J.; Chen, Gun-Shing; Lam, Jonathan; Balzer, Mark; Lo, John; Anderson, Mark; Schepis, Joseph P.

    2005-07-01

    During ground based life testing of a Microwave Limb Sounder (MLS) Antenna Actuator Assembly (AAA) ball-screw assembly, lubricant darkening and loss were noted when approximately 10% of required lifetime was completed. The MLS-AAA ball screw and nut are made from 17-4 PH steel, the nut has 440C stainless steel balls, and the assembly is lubricated with a Pennzane formulation containing a three weight percent lead naphthenate additive. Life tests were done in dry nitrogen at 50°C. To investigate the MLS-AAA life test anomaly, Spiral Orbit Tribometer (SOT) accelerated tests were performed. SOT results indicated greatly reduced relative lifetimes of Pennzane formulations in contact with 17-4 PH steel compared to 440C stainless steel. Also, dry nitrogen tests yielded longer relative lifetimes than comparable ultrahigh vacuum tests. Generally, oxidized Pennzane formulations yielded shorter lifetimes than non-oxidized lubricant. This study emphasizes surface chemistry effects on the lubricated lifetime of moving mechanical assemblies.

  16. OD17-7/2 Page 1 APICAL LESIONS

    E-print Network

    scar Surgical defect Periodontal disease Condensing osteitis Osteosclerosis Socket sclerosis Periapical activity) in surrounding bone signify an invasive process. #12;OD17-7/2 Page 4 PERIODONTAL SPACE WIDENING (Apical periodontitis) Radiographically, apparent widening (also called thickening) of the periodontal

  17. Stress corrosion study of PH13-8Mo stainless steel using the Slow Strain Rate Technique

    NASA Technical Reports Server (NTRS)

    Torres, Pablo D.

    1989-01-01

    The need for a fast and reliable method to study stress corrosion in metals has caused increased interest in the Slow Strain Rate Technique (SSRT) during the last few decades. PH13-8MoH950 and H1000 round tensile specimens were studied by this method. Percent reduction-in-area, time-to-failure, elongation at fracture, and fracture energy were used to express the loss in ductility, which has been used to indicate susceptibility to stress corrosion cracking (SCC). Results from a 3.5 percent salt solution (corrosive medium) were compared to those in air (inert medium). A tendency to early failure was found when testing in the vicinity of 1.0 x 10(-6) mm/mm/sec in the 3.5 percent salt solution. PH13-8Mo H1000 was found to be less likely to suffer SCC than PH13-8Mo H950. This program showed that the SSRT is promising for the SCC characterization of metals and results can be obtained in much shorter times (18 hr for PH steels) than those required using conventional techniques.

  18. Microstructure and dry-sliding wear properties of DC plasma nitrided 17-4 PH stainless steel

    NASA Astrophysics Data System (ADS)

    Li, Gui-jiang; Wang, Jun; Li, Cong; Peng, Qian; Gao, Jian; Shen, Bao-luo

    2008-05-01

    An attempt that the precipitation hardening steel 17-4PH was conducted by DC plasma nitriding (DCPN) is made to develop a kind of candidate material for nuclear reactor. Nitriding process performed at temperature ? 400 °C takes effect on creation of the layers composed of S-phase (expanded austenite) and ?N' (expanded martensite). Up to the temperature of 420 °C, the S-phase peaks disappear due to the transformation occurrence (S-phase ? ?N' + CrN). For the samples nitrided at temperature ? 450 °C, no evidence of ?N' is found owing to a precipitation ( ?N'??+CrN) taking place. For the 480 °C/4 h treated sample, it is the surface microhardness that plays the lead role in the wear rate reduction but the surface roughness; while for the 400 °C/4 h treated sample, it is both of the surface roughness and the S-phase formation. Dry sliding wear of the untreated 17-4PH is mainly characterized by strong adhesion, abrasion and oxidation mechanism. Samples nitrided at 400 °C which is dominated by slight abrasion and plastic deformation exhibit the best dry sliding wear resistance compared to the samples nitrided at other temperatures.

  19. The effect of microstructural evolution on hardening behavior of type 17-4PH stainless steel in long-term aging at 350 deg. C

    SciTech Connect

    Wang Jun [School of Materials Science and Engineering, Sichuan University, Chengdu, 610065 (China) and Nuclear Power Institute of China, Chengdu, 610041 (China)]. E-mail: srwangjun@163.com; Zou Hong [Nuclear Power Institute of China, Chengdu, 610041 (China); Li Cong [Nuclear Power Institute of China, Chengdu, 610041 (China); Qiu Shaoyu [Nuclear Power Institute of China, Chengdu, 610041 (China); Shen Baoluo [School of Materials Science and Engineering, Sichuan University, Chengdu, 610065 (China)

    2006-12-15

    The effect of microstructural evolution on hardening behavior of 17-4PH stainless steel in long-term aging at 350 deg. C was studied by X-ray diffraction and transmission electron microscopy. The results showed that there is the matrix of lath martensite and nanometer-sized particles of {epsilon}-Cu precipitated from the matrix after the alloy is solution treated and tempered. When the alloy was aged 350 deg. C for 9 months, {alpha}-{alpha}' spinodal decomposition occurred along the grain boundaries and caused an increase in hardness which compensated for the weakening effect due to ripening of the {epsilon}-copper precipitates. Upon further aging to 12 months, the Cr-rich {alpha}'-phase and M{sub 23}C{sub 6} precipitated, both of which strengthened the alloy considerably and led to enhanced hardening despite the continued softening by overaging of the {epsilon}-copper precipitates. With the aging time extended to 15 months, substantial reversed austenite transformed and precipitation of the intermetallic G-phase occurred near the {epsilon}-Cu precipitates in the matrix. The abundant amount of reversed austenite that transformed led to rapid softening.

  20. The Effect of 17-4 PH Stainless Steel on the Lifetime of a Pennzane(Trademark) Lubricated Microwave Limb Sounder Antenna Actuator Assembly Ball Screw for the AURA Spacecraft

    NASA Technical Reports Server (NTRS)

    Jones, William R., Jr.; Jansen, Mark J.; Chen, Gun-Shing; Lam, Jonathan; Balzer, Mark; Anderson, Mark; Lo, John; Schepis, Joseph P.

    2005-01-01

    During ground based life testing of a Microwave Limb Sounder (MLS) Antenna Actuator Assembly (AAA) ball-screw assembly, lubricant darkening and loss were noted when approximately 10 percent of required lifetime was completed. The MLS-AAA ball screw and nut are made from 17-4 PH steel, the nut has 440C stainless steel balls, and the assembly is lubricated with a Pennzane formulation containing a three weight percent lead naphthenate additive. Life tests were done in dry nitrogen at 50 C. To investigate the MLS-AAA life test anomaly, Spiral Orbit Tribometer (SOT) accelerated tests were performed. SOT results indicated greatly reduced relative lifetimes of Pennzane formulations in contact with 17-4 PH steel compared to 440C stainless steel. Also, dry nitrogen tests yielded longer relative lifetimes than comparable ultrahigh vacuum tests. Generally, oxidized Pennzane formulations yielded shorter lifetimes than non-oxidized lubricant. This study emphasizes surface chemistry effects on the lubricated lifetime of moving mechanical assemblies.

  1. Corrosion of nickel—chromium deposit on AISI 316L stainless steel in radioactive water with and without fluoride at pH 4

    Microsoft Academic Search

    G. Bellanger; J. J. Rameau

    1995-01-01

    The electrochemical behavior of samples was studied using potentiodynamic techniques at low scan rates, cyclic voltammetry at high scan rates and electrochemical impedance spectroscopy. The surfaces were examined and analyzed by scanning electron microscopy and X-ray microanalysis, respectively. The results from these different methods are discussed. They show that the deposit is more easily corroded than the AISI 316L stainless

  2. Corrosion of nickel—chromium deposit on AISI 316L stainless steel in radioactive water with and without fluoride at pH 4

    NASA Astrophysics Data System (ADS)

    Bellanger, G.; Rameau, J. J.

    1995-10-01

    The electrochemical behavior of samples was studied using potentiodynamic techniques at low scan rates, cyclic voltammetry at high scan rates and electrochemical impedance spectroscopy. The surfaces were examined and analyzed by scanning electron microscopy and X-ray microanalysis, respectively. The results from these different methods are discussed. They show that the deposit is more easily corroded than the AISI 316L stainless steel in presence or absence of fluoride. With fluoride and at the prepassive potentials, the Warburg straight line indicates that there is ionic diffusion in the nickel—chromium deposit oxide. The equivalent circuits for the nickel-chromium are proposed and indicate that the deposit can take part in localized corrosion. The use of high scan rates shows the transient kinetics of the oxide formation in presence of fluoride. With fluoride, the pitting currents are higher for nickel-chromium deposits. The SEM photographs and polarization curves show that the Ni?Cr deposit is locally corroded by fluoride, leading to the possibility of crevice formation under this and in 316L stainless steel.

  3. Fatigue Crack Growth under High Pressure of Gaseous Hydrogen in a 15-5PH Martensitic Stainless Steel: Influence of Pressure and Loading Frequency

    NASA Astrophysics Data System (ADS)

    Sun, Z.; Moriconi, C.; Benoit, G.; Halm, D.; Henaff, G.

    2013-03-01

    In this study, the effect of gaseous hydrogen pressure in relation with the loading frequency on the fatigue crack growth behavior of a precipitation-hardened martensitic stainless steel is investigated. It is found that increasing the hydrogen pressure from 0.09 to 9 MPa induces an enhancement of the fatigue crack growth rates. This enhancement is pronounced particularly at higher stress intensity factor amplitudes at 9 MPa. Meanwhile, decreasing the frequency from 20 to 0.2 Hz under 0.9 MPa of hydrogen reveals a significant increase in the crack growth rates that tends to join the curve obtained under 9 MPa at 20 Hz, but with a different cracking mode. However, it is shown that the degradation in fatigue crack growth behavior derives from a complex interaction between the fatigue damage and the amount of hydrogen enriching the crack tip, which is dependent on the hydrogen pressure, loading frequency, and stress intensity factor level. Scanning electron microscope (SEM) observations of the fracture surfaces are used to support the explanations proposed to account for the observed phenomena.

  4. Ultrasonic Spectroscopy of Stainless Steel Sandwich Panels

    NASA Technical Reports Server (NTRS)

    Cosgriff, Laura M.; Lerch, Bradley A.; Hebsur, Mohan G.; Baaklini, George Y.; Ghosn, Louis J.

    2003-01-01

    Enhanced, lightweight material systems, such as 17-4PH stainless steel sandwich panels are being developed for use as fan blades and fan containment material systems for next generation engines. In order to improve the production for these systems, nondestructive evaluation (NDE) techniques, such as ultrasonic spectroscopy, are being utilized to evaluate the brazing quality between the 17-4PH stainless steel face plates and the 17-4PH stainless steel foam core. Based on NDE data, shear tests are performed on sections representing various levels of brazing quality from an initial batch of these sandwich structures. Metallographic characterization of brazing is done to corroborate NDE findings and the observed shear failure mechanisms.

  5. 17.7% efficiency large area multicrystalline silicon solar cell using screen-printed metallization technique

    Microsoft Academic Search

    K. Fukui; S. Goto; J. Atobe; H. Hashigami; Y. Sakai; M. Tsuchida; Y. Inomata; S. Fujii; K. Shirasawa

    2005-01-01

    This paper describes the development of an industrial processing sequence that employs the screen printing and firing for large area multicrystalline silicon (mc-Si) solar cells. A record high efficiency mc-Si solar cell of 17.7%; cell area: 232.5 cm2 has been achieved using Kyocera's original cast mc-Si material. The diffusion length of mc-Si material was improved after cell processing especially at

  6. Bladed-shrouded-disc aeroelastic analyses: Computer program updates in NASTRAN level 17.7

    NASA Technical Reports Server (NTRS)

    Gallo, A. M.; Elchuri, V.; Skalski, S. C.

    1981-01-01

    In October 1979, a computer program based on the state-of-the-art compressor and structural technologies applied to bladed-shrouded-disc was developed. The program was more operational in NASTRAN Level 16. The bladed disc computer program was updated for operation in NASTRAN Level 17.7. The supersonic cascade unsteady aerodynamics routine UCAS, delivered as part of the NASTRAN Level 16 program was recorded to improve its execution time. These improvements are presented.

  7. Place Race No. Last Name First Name Time 1 423 Avis Charlie 17:17.7

    E-print Network

    Rowley, Clarence W.

    Place Race No. Last Name First Name Time 1 423 Avis Charlie 17:17.7 3 270 Zodda Jeffrey 19:51.6 8 337 Hoegler Kenric Molecular Biology 19:55.0 9 344 Harden Joshua Grad College 20:49.9 10:19.9 21 314 Soltes Garner Molecular Biology 22:39.3 22 310 UmanskyCastro Joshua Mathey 22:40.8 23 383

  8. 17-4 PH and 15-5 PH

    NASA Technical Reports Server (NTRS)

    Johnson, Howard T.

    1995-01-01

    17-4 PH and 15-5 PH are extremely useful and versatile precipitation-hardening stainless steels. Armco 17-4 PH is well suited for the magnetic particle inspection requirements of Aerospace Material Specification. Armco 15-5 PH and 17-4 PH are produced in billet, plate, bar, and wire. Also, 15-5 PH is able to meet the stringent mechanical properties required in the aerospace and nuclear industries. Both products are easy to heat treat and machine, making them very useful in many applications.

  9. Stress corrosion cracking evaluation of martensitic precipitation hardening stainless steels

    NASA Technical Reports Server (NTRS)

    Humphries, T. S.; Nelson, E. E.

    1980-01-01

    The resistance of the martensitic precipitation hardening stainless steels PH13-8Mo, 15-5PH, and 17-4PH to stress corrosion cracking was investigated. Round tensile and c-ring type specimens taken from several heats of the three alloys were stressed up to 100 percent of their yield strengths and exposed to alternate immersion in salt water, to salt spray, and to a seacoast environment. The results indicate that 15-5PH is highly resistant to stress corrosion cracking in conditions H1000 and H1050 and is moderately resistant in condition H900. The stress corrosion cracking resistance of PH13-8Mo and 17-4PH stainless steels in conditions H1000 and H1050 was sensitive to mill heats and ranged from low to high among the several heats included in the tests. Based on a comparison with data from seacoast environmental tests, it is apparent that alternate immersion in 3.5 percent salt water is not a suitable medium for accelerated stress corrosion testing of these pH stainless steels.

  10. The effect of indole on the corrosion behaviour of stainless steel

    Microsoft Academic Search

    Meltem Düdükcü; Birgül Yazici; Mehmet Erbil

    2004-01-01

    Indole was tested as a corrosion inhibitor for stainless steel (316L) in acidic and alkaline solutions (0.3M NaCl, pH = 4, 8 and 10). For this aim, current-potential curves and impedance measurements were used. All the experimental results showed that indole could provide an effective protection for stainless steel in chloride solution at pH = 4. The inhibiting effect of

  11. Chromium-Makes stainless steel stainless

    USGS Publications Warehouse

    Kropschot, S.J.; Doebrich, Jeff

    2010-01-01

    Chromium, a steely-gray, lustrous, hard metal that takes a high polish and has a high melting point, is a silvery white, hard, and bright metal plating on steel and other material. Commonly known as chrome, it is one of the most important and indispensable industrial metals because of its hardness and resistance to corrosion. But it is used for more than the production of stainless steel and nonferrous alloys; it is also used to create pigments and chemicals used to process leather.

  12. Growth of Si on Si(1 1 1)-7 × 7 at room temperature under laser substrate excitation

    NASA Astrophysics Data System (ADS)

    El-Kholy, Ibrahim; Elsayed-Ali, Hani E.

    2015-01-01

    The effect of laser substrate excitation on homoepitaxy of Si(1 1 1)-7 × 7 growth by femtosecond pulsed laser deposition is studied using reflection high-energy electron diffraction (RHEED). Laser excitation of the substrate with energy density significantly below its surface damage threshold results in a drastic change in the growth mode leading to epitaxial growth at room temperature. The morphology changes from rough surface with formation of clusters with different sizes for growth without laser excitation to oriented triangular-shaped islands with excitation. A nonthermal mechanism is responsible for the change in growth morphology with laser excitation increasing the adatom surface diffusion coefficient.

  13. Welding of Stainless Materials

    NASA Technical Reports Server (NTRS)

    Bull, H; Johnson, Lawrence

    1929-01-01

    It would appear that welds in some stainless steels, heat-treated in some practicable way, will probably be found to have all the resistance to corrosion that is required for aircraft. Certainly these structures are not subjected to the severe conditions that are found in chemical plants.

  14. A selective [4 + 2]-like cycloaddition of ?, ?-unsaturated ketone on Si(1 1 1)-7 × 7

    NASA Astrophysics Data System (ADS)

    Tang, Hai Hua; Cai, Ying Hui; Ning, Yue Sheng; Lai, Yee Hing; Xu, Guo Qin

    2007-08-01

    The interaction of ethyl vinyl ketone (EVK) with Si(1 1 1)-7 × 7 has been investigated using high-resolution electron energy loss spectroscopy (HREELS), X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations. The disappearance of both stretching vibrations of dbnd CH 2 (3099 cm -1) and C dbnd O (1684 cm -1) coupled with the appearance of new C dbnd C stretching mode (1660 cm -1) in the HREELS spectra of chemisorbed EVK clearly demonstrates the direct involvement of conjugated C dbnd C and C dbnd O bonds to form a SiC 1H 2C 2H dbnd C 3(C 4H 2C 5H 3)OSi surface species via [4 + 2]-like cycloaddition in a highly selective manner. In addition, XPS studies show that the C1s binding energies of C 1/C 2 and C 3 upon chemisorption display chemical downshifts of 0.8 eV and 2.2 eV, respectively, further confirming the proposed [4 + 2]-like cycloaddition reaction for the EVK/Si(1 1 1)-7 × 7 system. DFT theoretical calculations suggest that the proposed [4 + 2]-like cycloadduct is thermodynamically most favorable.

  15. Effect of microstructure on pitting and corrosion fatigue of 17-4 PH turbine blade steel in chloride environments

    Microsoft Academic Search

    B. C. Syrett; R. Viswanathan

    1982-01-01

    Depending on its heat treatment, 17-4 PH stainless steel may contain significant levels of reformed austenite and untempered martensite in a matrix of tempered martensite. Shot peening can cause changes in the microstructure of the surface layers by transforming the austenite to untempered martensite. The effect of these microstructural varations on the resistance of 17-4 PH stainless steel to pitting

  16. Passivation of stainless steel

    Microsoft Academic Search

    R. R Maller

    1998-01-01

    This paper, the 19th in a series of articles on the hygienic design of food processing equipment published in TIFS, introduces the first joint EHEDG\\/3-A Update article in the series, a set of guidelines for the hygienic passivation of stainless steel surfaces intended for food-contact use. These guidelines have been prepared on behalf of the US-based 3-A Steering Committee and

  17. Fatigue Properties of Stainless Steel Lap Joints. Spot welded, adhesive bonded, weldbonded, laser welded and clinched joints of stainless steel sheets-a review of their fatigue properties

    Microsoft Academic Search

    Hans Nordberg

    The type of joints covered are i) spot welded stainless to stainless and to galvanised carbon steel, ii) adhesive bonded stainless to stainless, iii) weld bonded stainless to stainless, iv) laser welded stainless to stainless and to galvanised carbon steel, v) clinched stainless to stainless steel. The materials studied are AISI 301 and 304 stainless steel and high strength duplex

  18. A SURVEY OF THE CORROSION OF MARTENSITIC AND FERRITIC STAINLESS STEELS IN PRESSURIZED WATER

    Microsoft Academic Search

    R. J. Beaver; C. F. Jr. Leitten

    1963-01-01

    The corrosion resistance of mantensitic and ferritic austenitic ; stainless steels and carbon steels in pressurized water at 500 to 600 deg F is ; compared. Included are specific out-of-pile data for austenitic stainless ; steels, AISI types types 410, 420, 431, and 440C; the ferritic AISI types 430, ; 442, and 446; the precipitation-hardening type 17-4PH; and carbon steels,

  19. Improvement of the thermal stability of sintered Nd-Fe-B magnets by intergranular addition of Dy{sub 82.3}Co{sub 17.7}

    SciTech Connect

    Zhang, Xiaofeng; Guo, Shuai; Yan, Changjiang; Cai, Lingwen; Chen, Renjie; Yan, Aru, E-mail: aruyan@nimte.ac.cn [Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang (China); Lee, Don [University of Dayton, Dayton, Ohio 45469 (United States)

    2014-05-07

    In this study, microstructure and magnetic properties of sintered Nd-Fe-B magnets with addition of Dy{sub 82.3}Co{sub 17.7} (wt.?%) were investigated. By adding a small amount of Dy{sub 82.3}Co{sub 17.7}, the coercivity is improved greatly, and the irreversible loss is decreased sharply. The increase of Curie temperature suggests that Co atoms have entered into the 2:14:1 main phase. Microstructural analysis indicates that a well-developed core-shell structure was formed in the magnets with the addition of Dy{sub 82.3}Co{sub 17.7}. The improvement of magnetic properties can be attributed to the microstructural modification and the intrinsic properties' improvement.

  20. Comparison of Stainless Steels in Simulated Paper Machine Environments

    Microsoft Academic Search

    T. M. J. Laitinen; T. M. J

    1999-01-01

    The localized corrosion behavior of austenitic stainless steels (SS) UNS S30403 and UNS S31603, and duplex SS UNS S31803 was compared in simulated paper machine environments containing chloride, sulfate, and thiosulfate at pH 3 and 65 C. Electrochemical testing of the materials was performed by cyclic polarization scans and scratch tests. Thiosulfate caused a remarkable decrease in repassivation potentials (E{sub

  1. Stainless steel decontamination manipulators

    SciTech Connect

    Sullivan, R.J.

    1986-01-01

    Three, large-volume coverage manipulator systems were designed and built for the Defense Water Processing Facility at the Savannah River Laboratory. These stainless steel systems will be used for high-pressure spray decontamination of waste containers and large process equipment modules. Each system has a manipulator arm, folding boom, and vertical drive and guide structure. Handling capacity is 45 kg, horizontal reach is 4.6 m with a 180-deg swing motion, and the vertical travel is 6 m. The system is remotely removable and replaceable in modules using an overhead crane and an impact wrench. The manipulator arm has seven motions: Shoulder rotation and pivot, elbow pivot, wrist pivot and rotation, and grip open-close. All motions are variable speed and are slip-clutch protected to prevent overloading from external forces (collisions).

  2. An Approximate Solution for Ph/Ph/1 and Ph/Ph/1/N Queues

    E-print Network

    Begin, Thomas

    An Approximate Solution for Ph/Ph/1 and Ph/Ph/1/N Queues Alexandre Brandwajn Baskin School approximation to assess the steady-state probabilities of the number of customers in Ph/Ph/1 and Ph/Ph/1/N for the Ph/Ph/1/N queue. The phase-type distributions considered are assumed to be acyclic. Our method

  3. Brazing titanium to stainless steel

    NASA Technical Reports Server (NTRS)

    Batista, R. I.

    1980-01-01

    Titanium and stainless-steel members are usually joined mechanically for lack of any other effective method. New approach using different brazing alloy and plating steel member with nickel resolves problem. Process must be carried out in inert atmosphere.

  4. Weld microstructure development and properties of precipitation-strengthened martensitic stainless steels

    Microsoft Academic Search

    J. A. Brooks; W. R. Jr. Garrison

    1999-01-01

    The weld microstructural evolution, mechanical properties and solidification cracking susceptibility of three precipitation-strengthened martensitic stainless steels--PH 13-8 Mo, Custom 450 and 15-5 PH--were investigated. Liquid tin quenching of gas tungsten arc welds revealed that all three welds solidified as single-phase ferrite with a high degree of microsegregation. However, during further solidification and cooling almost complete homogenization occurred as a result

  5. Interaction of cobalt with a stainless steel oxide surface

    SciTech Connect

    Taylor, J.B. (British Nuclear Fuels PLC, Risley (England))

    1991-01-01

    The deposition of radioactive cobalt ions from aqueous solutions in the pH range from 1 to 12 onto the internal surface of a stainless steel vessel or pipework can lead to the buildup of tenacious surface activity. For liquid streams of low specific activity (measured in becquerels per millilitre), the surface activity buildup may create a more dominant gamma radiation field than the activity suspended in the liquid. Failure to adequately predict this buildup for an operational nuclear plant can lead to an underestimate of potential gamma dose rates. This may lead to an economic penalty if additional shielding or other protective measures are necessary following plant operation. A theoretical method of determining the cobalt mass/activity deposition from aqueous liquor onto stainless steel is outlined in this paper. A validation of the method is given, and the limits of its application are discussed.

  6. Achievement of a superpolish on bare stainless steel

    NASA Astrophysics Data System (ADS)

    Howells, Malcolm R.; Casstevens, John M.

    1997-11-01

    We report the achievement of a superpolished surface, suitable for x-ray reflection, on bare stainless steel. The rms roughness obtained on various samples varied from 2.2 to 4.2 angstroms, as measured by an optical profiler with a bandwidth 0.29 - 100 mm-1. The type 17-4 PH precipitation-hardening stainless steel used to make the mirrors is also capable of ultrastability and has good manufacturability. This combination of properties makes it an excellent candidate material for mirror substrates. We describe the successful utilization of this type of steel in making elliptical-cylinder mirrors for a soft-x-ray microprobe system at the Advanced Light Source, and discuss possible reasons for its unusual stability and polishability.

  7. Stress-corrosion cracking of sensitized type 304 stainless steel in thiosulfate solutions

    Microsoft Academic Search

    R. C. Newman; K. Sieradzki; H. S. Isaacs

    1982-01-01

    The stress corrosion cracking of a sensitized Type 304 stainless steel has been studied at room temperature using controlled potentials and two concentrations of sodium thiosulfate. In both constant extension rate and constant load tests, the crack velocities attain extremely high values, up to 8 mum s-1. Scratching electrode experiments conducted at various pH values on simulated grain boundary material

  8. Characteristics of VHF radiowave scintillations over a solar cycle (1983–1993) at a low-latitude station: Waltair (17.7°N, 83.3°E)

    Microsoft Academic Search

    P. V. S. Rama Rao; P. T. Jayachandran; P. Sri Ram; B. V. Ramana Rao; D. S. V. V. D. Prasad; K. K. Rose

    1997-01-01

    The characteristics of VHF radiowave scintillations at 244 MHz (FLEETSAT) during a complete solar cycle (1983–93) at a low-latitude station, Waltair (17.7°N, 83.3°E), are presented. The occurrence of night-time scintillations shows equinoctial maxima and summer minima in all the epochs of solar activity, and follows the solar activity. The daytime scintillation occurrence is negatively correlated with the solar activity and

  9. Rapid screening of stainless steels for environmental cracking

    SciTech Connect

    Kane, R.D. [CLI International, Inc., Houston, TX (United States); Joia, C.J.B.M. [Centro de Pesquisas da Petrobras, Rio de Janeiro (Brazil); Small, A.L.L.T.; Ponciano, J.A.C. [Univ. Federal do Rio de Janeiro (Brazil). Dept. de Engenharia Metalurgica

    1997-09-01

    An evaluation of tubular materials for a new offshore oil and gas development was conducted. The project requirements were for an initial, preliminary assessment of materials with limited time. Slow strain rate testing was conducted in an aqueous environment containing 150,000 ppm Cl{sup {minus}} with 900 kPa carbon dioxide (CO{sub 2}) and 10 kPa hydrogen sulfide (H{sub 2}S) at three levels of pH and temperature. Worst-case performance diagrams were developed that showed the utility of selected stainless steels.

  10. Shrinkage Prediction for the Investment Casting of Stainless Steels

    SciTech Connect

    Sabau, Adrian S [ORNL

    2007-01-01

    In this study, the alloy shrinkage factors were obtained for the investment casting of 17-4PH stainless steel parts. For the investment casting process, unfilled wax and fused silica with a zircon prime coat were used for patterns and shell molds, respectively. Dimensions of the die tooling, wax pattern, and casting were measured using a Coordinate Measurement Machine in order to obtain the actual tooling allowances. The alloy dimensions were obtained from numerical simulation results of solidification, heat transfer, and deformation phenomena. The numerical simulation results for the shrinkage factors were compared with experimental results.

  11. EAF STAINLESS STEEL DUST PROCESSING

    Microsoft Academic Search

    G. M. Denton; N. A. Barcza; P. D. Scott; T. Fulton

    During the production of stainless steel iron, between 30 and 70 kg of dust and fine waste is generated per ton of steel. Mintek has developed the EnviroplasTM process for the treatment of solid wastes from the metallurgical industry, especially steel plant dusts, without requiring agglomeration to produce inert slag and at the same time recover metal values such as

  12. Comparative Study on the Corrosion Resistance of Fe-Based Amorphous Metal, Borated Stainless Steel and Ni-Cr-Mo-Gd Alloy

    SciTech Connect

    Lian, Tiangan; Day, Daniel; Hailey, Phillip; Choi, Jor-Shan; Farmer, Joseph [Lawrence Livermore National Laboratory, Livermore, CA, 94550 (United States)

    2007-07-01

    Iron-based amorphous alloy Fe{sub 49.7}Cr{sub 17.7}Mn{sub 1.9}Mo{sub 7.4}W{sub 1.6}B{sub 15.2}C{sub 3.8}Si{sub 2.4} was compared to borated stainless steel and Ni-Cr-Mo-Gd alloy on their corrosion resistance in various high-concentration chloride solutions. The melt-spun ribbon of this iron-based amorphous alloy have demonstrated a better corrosion resistance than the bulk borated stainless steel and the bulk Ni-Cr-Mo-Gd alloy, in high-concentration chloride brines at temperatures 90 deg. C or higher. (authors)

  13. Nickel release from stainless steels.

    PubMed

    Haudrechy, P; Mantout, B; Frappaz, A; Rousseau, D; Chabeau, G; Faure, M; Claudy, A

    1997-09-01

    In 1994, a study of nickel release and allergic contact dermatitis from nickel-plated metals and stainless steels was published in this journal. It was shown that low-sulfur stainless steel grades like AISI 304, 316L or 430 (S < or = 0.007%) release less than 0.03 microgram/cm2/week of nickel in acid artificial sweat and elicit no reactions in patients already sensitized to nickel. In contrast, nickel-plated samples release around 100 micrograms/cm2/week of Ni and high-sulfur stainless steel (AISI 303-S approximately 0.3%) releases about 1.5 micrograms/cm2/week in this acid artificial sweat. Applied on patients sensitized to nickel, these metals elicit positive reactions in 96% and 14%, respectively, of the patients. The main conclusion was that low-sulfur stainless steels like AISI 304, 316L or 430, even when containing Ni, should not elicit nickel contact dermatitis, while metals having a mean corrosion resistance like a high-sulfur stainless steel (AISI 303) or nickel-plated steel should be avoided. The determining characteristic was in fact the corrosion resistance in chloride media, which, for stainless steels, is connected, among other factors, to the sulfur content. Thus, a question remained concerning the grades with an intermediate sulfur content, around 0.03%, which were not studied. They are the object of the study presented in this paper. 3 tests were performed: leaching experiments, dimethylglyoxime and HNO3 spot tests, and clinical patch tests; however, only stainless steels were tested: a low-sulfur AISI 304 and AISI 303 as references and 3 grades with a sulfur content around 0.03%: AISI 304L, AISI 304L added with Ca, AISI 304L+Cu. Leaching experiments showed that the 4 non-resulfurised grades released less than 0.5 microgram/cm2/week in acid sweat while the reulfurized AISI 303 released around or more than 0.5 microgram/cm2/week. This is explained by the poorer corrosion resistance of the resulfurized grade. Yet all these grades had the same reaction to the DMG test (negative result), which shows again its lack of sensitivity. In contrast, the HNO3 spot test distinguished AISI 303 from the non-resulfurized grades. Clinical patch tests again showed that some patients (4%) were intolerant to AISI 303, while none were intolerant to the other grades. Thus, this study confirms that non-resulfurized stainless steels (S < or = 0.03%) like Ni-containing 304 and 304L should not elicit Ni contact dermatitis, while the resulfurized grades (S > 0.1%) should be avoided. PMID:9330816

  14. Intergranular corrosion of stainless steel

    Microsoft Academic Search

    J. Stewart; D. B. Wells; P. M. Scott; D. E. Williams

    1991-01-01

    Corrosion current pulses associated with the nucleation of microcracks and their movement across single grain boundary facets were detected for intergranular stress corrosion cracking (IGSCC) of sensitized type 304 stainless steel induced both by dilute thiosulphate solutions at ambient temperature and by high-purity oxygenated water at 289°C (BWR conditions). Estimates of crack-tip dissolution width and current density were derived. Cracks

  15. Comminution of stainless steel powders

    Microsoft Academic Search

    B. A. Borok; R. P. Schchegoleva; L. S. Golubeva; F. S. Sariadi; E. M. Rabinovich

    1974-01-01

    1.Atmospheric milling in barrel type mixers at a powder-to-ball weight ratio of 1::2 is an effective means of comminuting stainless steel powders produced by the coreduction process. In the work described, milling for 27 h was found to increase the amount of the -0.063-mm fraction from ~15 to ~75% for a Kh18N15 steel powder and from ~24.6 to ~70%for a

  16. Nickel: makes stainless steel strong

    USGS Publications Warehouse

    Boland, Maeve A.

    2012-01-01

    Nickel is a silvery-white metal that is used mainly to make stainless steel and other alloys stronger and better able to withstand extreme temperatures and corrosive environments. Nickel was first identified as a unique element in 1751 by Baron Axel Fredrik Cronstedt, a Swedish mineralogist and chemist. He originally called the element kupfernickel because it was found in rock that looked like copper (kupfer) ore and because miners thought that "bad spirits" (nickel) in the rock were making it difficult for them to extract copper from it. Approximately 80 percent of the primary (not recycled) nickel consumed in the United States in 2011 was used in alloys, such as stainless steel and superalloys. Because nickel increases an alloy's resistance to corrosion and its ability to withstand extreme temperatures, equipment and parts made of nickel-bearing alloys are often used in harsh environments, such as those in chemical plants, petroleum refineries, jet engines, power generation facilities, and offshore installations. Medical equipment, cookware, and cutlery are often made of stainless steel because it is easy to clean and sterilize. All U.S. circulating coins except the penny are made of alloys that contain nickel. Nickel alloys are increasingly being used in making rechargeable batteries for portable computers, power tools, and hybrid and electric vehicles. Nickel is also plated onto such items as bathroom fixtures to reduce corrosion and provide an attractive finish.

  17. 77 FR 64545 - Drawn Stainless Steel Sinks From China

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-22

    ...countertop). Stainless steel sinks with multiple drawn...are joined through a welding operation to form one...bending the stainless steel, and then welding and finishing the vertical...the bowls. Stainless steel sinks with...

  18. Effect of acetic NaF solution on the corrosion behavior of stainless steel orthodontic brackets.

    PubMed

    Jang, Hee-Song; Son, Woo-Sung; Park, Soo-Byung; Kim, Hyung-Il; Yong, Hoon Kwon

    2006-06-01

    This study assessed the effect of acetic NaF solutions on stainless steel orthodontic brackets. Acetic acid was added to a 0.1% NaF solution to make two solutions, one with pH 3.5 and the other with pH 6. For the two different stainless steel brackets (Tomy, Dentaurum) used in this study, they had a similar elemental composition--except with Mo (molybdenum) in the Tomy bracket. The brackets were then immersed in the prepared test solutions for three days and their responses evaluated. In terms of hydrofluoric acid (HF) concentration, the 0.1%/pH 3.5 solution showed a high HF concentration at 227 ppm, while that of 0.1%/pH 6 solution was very low at 7 ppm. In terms of color change and element release, only the Dentaurum brackets in 0.1%/pH 3.5 solution showed an appreciable color change (deltaE* = 4.0) and released a great amount of elements (Fe, Cr, Ni, Mn) after three days. Otherwise, regardless of pH value and product, only minor color change (deltaE* < 1.0) and negligible element release occurred. In terms of surface modification, no visible changes in surface morphology were observed in any product after immersion in test solutions. PMID:16916238

  19. Predicted High-Temperature Superconducting State in the Hydrogen-Dense Transition-Metal Hydride YH3 at 40K and 17.7GPa

    NASA Astrophysics Data System (ADS)

    Kim, Duck Young; Scheicher, Ralph H.; Ahuja, Rajeev

    2009-08-01

    Metallization in pure hydrogen has been proposed to give rise to high-temperature superconductivity at pressures which still lie beyond the reach of contemporary experimental techniques. Hydrogen-dense materials offer an opportunity to study related phenomena at experimentally achievable pressures. Here we report the prediction of high-temperature superconductivity in yttrium hydride (YH3), with a Tc of 40 K at 17.7 GPa, the lowest reported pressure for hydrogen-dense materials to date. Specifically, we find that the face-centered cubic structure of YH3 exhibits superconductivity of different origins in two pressure regions. The evolution of Tc with pressure follows the corresponding change of s-d hybridization between H and Y, due to an enhancement of the electron-phonon coupling by a matching of the energy level from Y-H vibrations with the peak of the s electrons from the octahedrally coordinated hydrogen atoms.

  20. Predicted high-temperature superconducting state in the hydrogen-dense transition-metal hydride YH3 at 40 K and 17.7 GPa.

    PubMed

    Kim, Duck Young; Scheicher, Ralph H; Ahuja, Rajeev

    2009-08-14

    Metallization in pure hydrogen has been proposed to give rise to high-temperature superconductivity at pressures which still lie beyond the reach of contemporary experimental techniques. Hydrogen-dense materials offer an opportunity to study related phenomena at experimentally achievable pressures. Here we report the prediction of high-temperature superconductivity in yttrium hydride (YH3), with a T(c) of 40 K at 17.7 GPa, the lowest reported pressure for hydrogen-dense materials to date. Specifically, we find that the face-centered cubic structure of YH3 exhibits superconductivity of different origins in two pressure regions. The evolution of T(c) with pressure follows the corresponding change of s-d hybridization between H and Y, due to an enhancement of the electron-phonon coupling by a matching of the energy level from Y-H vibrations with the peak of the s electrons from the octahedrally coordinated hydrogen atoms. PMID:19792676

  1. Stress-corrosion cracking of sensitized type 304 stainless steel in thiosulfate solutions

    Microsoft Academic Search

    R. C. Newman; K. Sieradzki; H. S. Isaacs

    1982-01-01

    The stress corrosion cracking of a sensitized Type 304 stainless steel has been studied at room temperature using controlled\\u000a potentials and two concentrations of sodium thiosulfate. In both constant extension rate and constant load tests, the crack\\u000a velocities attain extremely high values, up to 8 ?m s-1. Scratching electrode experiments conducted at various pH values on simulated grain boundary material

  2. Friction and wear of stainless steels implanted with Ti and C

    Microsoft Academic Search

    F. G. Yost; L. E. Pope; D. M. Follstaedt; J. A. Knapp; S. T. Picraux

    1981-01-01

    Friction and wear tests were completed on Fe and stainless steels of the type 304, 15-5 pH, Nitronic 60, and 440C implanted with Ti and C. Samples were mechanically polished prior to ion implantation to fluences of 2 x 10¹⁷ Ti\\/cm² (90 to 180 keV) and 2 x 10¹⁷ C\\/cm² (30 keV); the implantation profiles of the two elements overlapped

  3. High corrosion resistance of austenitic stainless steel alloyed with nitrogen in an acid solution

    Microsoft Academic Search

    M. Metikoš-Hukovi?; R. Babi?; Z. Gruba?; Ž. Petrovi?; N. Lajçi

    2011-01-01

    Passivity of austenitic stainless steel containing nitrogen (ASS N25) was investigated in comparison with AISI 316L in deareated acid solution, pH 0.4. A peculiar nature of the passivation peak in a potentiodynamic curve and the kinetic parameters of formation and growth of the oxide film have been discussed. The electronic-semiconducting properties of the passive films have been correlated with their

  4. Diffusion brazing nickel-plated stainless steel

    NASA Technical Reports Server (NTRS)

    Beuyukian, C. S.; Mitchell, M. J.

    1976-01-01

    To bond parts, sandwich assembly is made up of aluminum core, aluminum face sheet with brazing alloy interface, and nickel plated stainless steel part. Sandwich is placed between bottom and top glide sheet that is placed in stainless steel retort where assembly is bonded at 580 C.

  5. Weldability of duplex stainless steel pipelines

    Microsoft Academic Search

    A. C. Madsen; F. O. Mueller; J. B. Jee

    1987-01-01

    In a previous study, Standard Oil Production Company determined that duplex stainless steel conforming to UNS S31803 would be acceptable for piping and pipeline applications on the North Slope of Alaska. In consideration of the above studies as well as information contained in the literature or provided by suppliers, Standard Oil decided to utilize UNS S31803 duplex stainless steel for

  6. The stainless steel beneficial reuse integrated demonstration

    Microsoft Academic Search

    W. L. Boettinger; R. N. Lutz

    1994-01-01

    Process water heat exchangers at SRS contains over 95% 304 stainless steel which could be recycled back to DOE in a ``controlled release`` manner, that is, the radioactive scrap metal (RSM) could be reprocessed into new reusable products for return to DOE for use within the DOE Complex. In 1994, a demonstration was begun to recycle recycle contaminated stainless steel

  7. Ultrasonic properties of austenitic stainless steel welds

    Microsoft Academic Search

    Lott

    1980-01-01

    Measurements of ultrasonic velocity and attenuation were made on welded austenitic stainless steel specimens, and data correlated to flaw detectability. Measurements were made at 2.25 MHz for both longitudinal and shear waves as functions of propagation and polarization directions. The results of ultrasonic velocity measurements show that, in stainless steel welds, a high degree of anisotropy exists with respect to

  8. Interaction between stainless steel and plutonium metal

    SciTech Connect

    Dunwoody, John T [Los Alamos National Laboratory; Mason, Richard E [Los Alamos National Laboratory; Freibert, Franz J [Los Alamos National Laboratory; Willson, Stephen P [Los Alamos National Laboratory; Veirs, Douglas K [Los Alamos National Laboratory; Worl, Laura A [Los Alamos National Laboratory; Archuleta, Alonso [Los Alamos National Laboratory; Conger, Donald J [Los Alamos National Laboratory

    2010-01-01

    Long-term storage of excess plutonium is of great concern in the U.S. as well as abroad. The current accepted configuration involves intimate contact between the stored material and an iron-bearing container such as stainless steel. While many safety scenario studies have been conducted and used in the acceptance of stainless steel containers, little information is available on the physical interaction at elevated temperatures between certain forms of stored material and the container itself. The bulk of the safety studies has focused on the ability of a package to keep the primary stainless steel containment below the plutonium-iron eutectic temperature of approximately 410 C. However, the interactions of plutonium metal with stainless steel have been of continuing interest. This paper reports on a scoping study investigating the interaction between stainless steel and plutonium metal in a pseudo diffusion couple at temperatures above the eutectic melt-point.

  9. A stainless steel bracket for orthodontic application.

    PubMed

    Oh, Keun-Taek; Choo, Sung-Uk; Kim, Kwang-Mahn; Kim, Kyoung-Nam

    2005-06-01

    Aesthetics has become an essential element when choosing orthodontic fixed appliances. Most metallic brackets used in orthodontic therapy are made from stainless steel (SS) with the appropriate physical properties and good corrosion resistance, and are available as types 304, 316 and 17-4 PH SS. However, localized corrosion of these materials can frequently occur in the oral environment. This study was undertaken to evaluate the accuracy of sizing, microstructure, hardness, corrosion resistance, frictional resistance and cytotoxicity of commercially available Mini-diamond (S17400), Archist (S30403) and experimentally manufactured SR-50A (S32050) brackets. The size accuracy of Mini-diamond was the highest at all locations except for the external horizontal width of the tie wing (P < 0.05). Micrographs of the Mini-diamond and Archist showed precipitates in the grains and around their boundaries. SR-50A showed the only austenitic phase and the highest polarization resistance of the tested samples. SR-50A also had the highest corrosion resistance [SR-50A, Mini-diamond and Archist were 0.9 x 10(-3), 3.7 x 10(-3), and 7.4 x 10(-3) mm per year (mpy), respectively], in the artificial saliva. The frictional force of SR-50A decreased over time, but that of Mini-diamond and Archist increased. Therefore, SR-50A is believed to have better frictional properties to orthodontic wire than Mini-diamond and Archist. Cytotoxic results showed that the response index of SR-50A was 0/1 (mild), Mini-diamond 1/1 (mild+), and Archist 1/2 (mild+). SR-50A showed greater biocompatibility than either Mini-diamond or Archist. It is concluded that the SR-50A bracket has good frictional property, corrosion resistance and biocompatibility with a lower probability of allergic reaction, compared with conventionally used SS brackets. PMID:15947222

  10. Development of New Stainless Steel

    SciTech Connect

    Robert F. Buck

    2005-08-30

    A new family of innovative martensitic stainless steels, 521-A, 521-B, and 521-C has been developed by Advanced Steel Technology, LLC (Trafford, PA) as high strength fastener (bolt) materials for use at moderate temperatures in turbine engines, including steam turbines, gas turbines, and aircraft engines. The primary objective of the development program was to create a martensitic stainless steel with high strength at moderate temperatures, and which could replace the expensive nickel-based superalloy IN 718 in some fasteners applications. A secondary objective was to replace conventional 12Cr steels such as AISI 422 used as blades, buckets and shafts that operate at intermediate temperatures in turbine engines with stronger steel. The composition of the new alloys was specifically designed to produce excellent mechanical properties while integrating heat treatment steps into production to reduce energy consumption during manufacturing. As a result, production costs and energy consumption during production of rolled bar products is significantly lower than conventional materials. Successful commercialization of the new alloys would permit the installed cost of certain turbine engines to be reduced without sacrificing high availability or operational flexibility, thereby enhancing the global competitiveness of U.S. turbine engine manufacturers. Moreover, the domestic specialty steel industry would also benefit through increased productivity and reduced operating costs, while increasing their share of the international market for turbine engine fasteners, blades, buckets and shafts.

  11. A porous stainless steel membrane system for extraterrestrial crop production

    NASA Technical Reports Server (NTRS)

    Koontz, H. V.; Prince, R. P.; Berry, W. L.; Knott, W. M. (Principal Investigator)

    1990-01-01

    A system was developed in which nutrient flow to plant roots is controlled by a thin (0.98 or 1.18 mm) porous (0.2 or 0.5 microns) stainless steel sheet membrane. The flow of nutrient solution through the membrane is controlled by adjusting the relative negative pressure on the nutrient solution side of the membrane. Thus, the nutrient solution is contained by the membrane and cannot escape from the compartment even under microgravity conditions if the appropriate pressure gradient across the membrane is maintained. Plant roots grow directly on the top surface of the membrane and pull the nutrient solution through this membrane interface. The volume of nutrient solution required by this system for plant growth is relatively small, since the plenum, which contains the nutrient solution in contact with the membrane, needs only to be of sufficient size to provide for uniform flow to all parts of the membrane. Solution not passing through the membrane to the root zone is recirculated through a reservoir where pH and nutrient levels are controlled. The size of the solution reservoir depends on the sophistication of the replenishment system. The roots on the surface of the membrane are covered with a polyethylene film (white on top, black on bottom) to maintain a high relative humidity and also limit light to prevent algal growth. Seeds are sown directly on the stainless steel membrane under the holes in the polyethylene film that allow a pathway for the shoots.

  12. A porous stainless steel membrane system for extraterrestrial crop production.

    PubMed

    Koontz, H V; Prince, R P; Berry, W L

    1990-06-01

    A system was developed in which nutrient flow to plant roots is controlled by a thin (0.98 or 1.18 mm) porous (0.2 or 0.5 microns) stainless steel sheet membrane. The flow of nutrient solution through the membrane is controlled by adjusting the relative negative pressure on the nutrient solution side of the membrane. Thus, the nutrient solution is contained by the membrane and cannot escape from the compartment even under microgravity conditions if the appropriate pressure gradient across the membrane is maintained. Plant roots grow directly on the top surface of the membrane and pull the nutrient solution through this membrane interface. The volume of nutrient solution required by this system for plant growth is relatively small, since the plenum, which contains the nutrient solution in contact with the membrane, needs only to be of sufficient size to provide for uniform flow to all parts of the membrane. Solution not passing through the membrane to the root zone is recirculated through a reservoir where pH and nutrient levels are controlled. The size of the solution reservoir depends on the sophistication of the replenishment system. The roots on the surface of the membrane are covered with a polyethylene film (white on top, black on bottom) to maintain a high relative humidity and also limit light to prevent algal growth. Seeds are sown directly on the stainless steel membrane under the holes in the polyethylene film that allow a pathway for the shoots. PMID:11537562

  13. Arts & Letters 2006-07 2007-08 2008-09 2009-10 2010-11 2011-12 BA 18.5 28.5 17.7 22 21 26.5 43%

    E-print Network

    Fernandez, Eduardo

    Arts & Letters 2006-07 2007-08 2008-09 2009-10 2010-11 2011-12 5 Yr % Change BA 18.5 28.5 17.7 22 21 26.5 43% MA 2 6 6 8 2 5 150% MAT 0 0 0 0 0 1 n/c BA 0 1 0 0 0 0 0% BFA 1 4 0 0 0 0 -100% MFA 0 0 1 0 0 0 0% Art - Computer Arts in Animation BFA 22 25 17 7.5 4 4 -82% BA 0 0 0 0 1 1 n/c BFA 0 0 0 0 4

  14. 76 FR 87 - Grant of Authority for Subzone Status; ThyssenKrupp Steel and Stainless USA, LLC; (Stainless and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-03

    ...Grant of Authority for Subzone Status; ThyssenKrupp Steel and Stainless USA, LLC; (Stainless...products manufacturing facility of ThyssenKrupp Steel and Stainless USA, LLC, located...carbon steel products at the facility of ThyssenKrupp Steel and Stainless USA, LLC,...

  15. Isomeric effects on room-temperature chemisorption and thermal evolution of iso-, cis- and trans-dichloroethylene on Si(1 1 1)7 × 7

    NASA Astrophysics Data System (ADS)

    He, Zhenhua; Li, Q.; Leung, K. T.

    2006-02-01

    The room-temperature adsorption and thermal evolution of iso-, cis- and trans-dichloroethylene (DCE) on Si(1 1 1)7 × 7 have been studied by vibrational electron energy loss spectroscopy and thermal desorption spectrometry (TDS). The presence of the Si-Cl stretch at 510 cm -1 suggests that, upon adsorption, all three isomers dissociate via C-Cl bond breakage on the 7 × 7 surface to form mono-? bonded chlorovinyl (HC?dbnd CHCl or ClC?dbnd CH2), which could, in the case of iso-DCE, further dechlorinate to vinylidene (:C dbnd CH 2) upon insertion into the back-bond. The higher saturation exposure for the Si-Cl stretch at 510 cm -1 observed for cis- and trans-DCE than iso-DCE suggests that Cl dissociation via the dbnd CHCl group in the cis and trans isomers is less readily than the dbnd CCl 2 group in iso-DCE. Our TDS data show remarkable similarities in both molecular desorption near 360 K and thermal evolution of the respective adstructures for all three isomers on Si(1 1 1)7 × 7. In particular, upon annealing to 450 K, the mono-? bonded chlorovinyl adspecies is found to further dechlorinate to either vinylene (HC?dbnd C?H) di-? bonded to the Si surface or acetylene to be released from the surface. Above 580 K, vinylene could also become gaseous acetylene or undergo H abstraction to produce hydrocarbon or SiC fragments. All three DCE isomers also exhibit TDS features attributable to an etching product SiCl 2 at 800-950 K and recombinative desorption products HCl at 700-900 K and H 2 at 650-820 K. The stronger Cl-derived TDS signals and Si-Cl stretch at 510 cm -1 over 450-820 K for trans-DCE than those for cis-DCE indicate stronger dechlorination for trans-DCE than cis-DCE, which could be due to less steric hindrance resulting from the formation of the chlorovinyl adspecies for trans-DCE during the initial adsorption/dechlorination process. Finally, our density functional calculations qualitatively support the thermodynamic feasibility and relative stabilities of the proposed adstructures involving chlorovinyl, vinylidene, and vinylene adspecies.

  16. [Study of a new medical stainless steel].

    PubMed

    Ren, Yibin; Yang, Ke; Zhang, Bingchun; Yang, Huibin

    2006-10-01

    Medical implantable stainless steels are widely used in medical field due to their excellent properties, besides its allergic response to human body, the nickel ion released from the steels due to corrosion has the harm of malformation and carcingenesis. The mechanical property, corrosion resistance and blood compatibility of a new nickel-free stainless steel (BIOSSN4) is researched in this paper. Compared with the traditional 316L medical stainless steel, BIOSSN4 shows wide future applications because of its better combination of strength and toughness, good corrosion resistance and biocompatibility. PMID:17121363

  17. Chemical composition of passive films on AISI 304 stainless steel

    SciTech Connect

    Lorang, G.; Da Cunha Belo, M. (Centre E'Etudes de Chimie Metallurgique du CNRS, Vitry-Sur-Seine (France)); Simoes, A.M.P.; Ferreira, M.G.S. (Inst. Superior Tecnico, Lisboa (Portugal). Dept. de Engenharia Quimica)

    1994-12-01

    Chemical characterization of passive films formed on AISI 304 austenitic stainless steel, in a borate/boric acid solution at pH 9.2, under various conditions of potential, temperature, and polarizations time, was made by Auger electron spectroscopy combined with ion sputtering, and x-ray photoelectron spectroscopy (XPS). The depth chemical composition, thickness, and duplex character of the passive layers were determined after processing AES sputter profiles by their quantitative approach based on the sequential layer sputtering model. Moreover, separated contributions of elements in their oxidized and unoxidized state could be disclosed from part to part of the oxide-alloy interface. The XPS study specified the chemical bondings which take placed inside the film, between Fe and oxygen (and water).

  18. Corrosion resistance of stainless steels in seawater

    SciTech Connect

    Dundas, J.J.; Bond, A.P.

    1985-10-01

    The resistance of commercial and laboratory produced stainless steels to crevice corrosion was evaluated by a 60-day exposure in filtered seawater at 25 C. The results in seawater were compared to laboratory tests in 10% FeCl/sub 3/. The results in seawater were compared to laboratory tests in 10% FeCl/sub 3/. Austenitic, ferritic, and duplex stainless steels containing a minimum of 25% Cr-5% Mo, 27% Cr-3.4% Mo and 25% Cr-3.2% Mo, respectively, were resistant to crevice corrosion in 25 C seawater. The austenitic stainless steels also required a minimum of 0.2% N. Significant reductions in either the chromium or molybdenum content caused substantial attack. There was a good correlation between the laboratory tests in 10% FeCl/sub 3/ and the seawater test for the ferritic and duplex stainless steels but not for the austenitic grades.

  19. Development of a carburizing stainless steel alloy

    SciTech Connect

    Wert, D.E. (Carpenter Technology Corp., Reading, PA (United States))

    1994-06-01

    A new carburizing stainless steel alloy that resists corrosion, heat, and fatigue has been developed for bearing and gear applications. Pyrowear 675 Stainless alloy is vacuum induction melted and vacuum arc remelted (VIM/VAR) for aircraft-quality cleanliness. Test results show that it has corrosion resistance similar to that of AISI Type 440-C stainless, and its rolling fatigue resistance is superior to that of AISI M50 (UNS K88165). In contrast to alloy gear steels and Type 440C, Pyrowear 675 maintains case hardness of HRC 60 at operating temperatures up to 200 C (400 F). Impact and fracture toughness are superior to that of other stainless bearing steels, which typically are relatively brittle and can break under severe service. Toughness is also comparable or superior to conventional noncorrosion-resistant carburizing bearing steels, such as SAE Types 8620 and 9310.

  20. Study of Alumina in Austenitic Stainless Steels 

    E-print Network

    Wang, Chung

    2014-12-18

    model supports the major conclusion that the combination of third element phenomena, oxide transport properties, material thermodynamics and kinetics can be used to provide accurate insight on the formation of alumina for austenitic stainless steel....

  1. Porous sintered materials from stainless steel

    Microsoft Academic Search

    R. A. Andrievskii; V. S. Pugin; I. M. Fedorchenko; B. Z. Teverovskii

    1965-01-01

    1.A method is proposed for the production of long, high-porosity tubes from nonspherical stainless steel powders.2.A study was made of the mechanical, electrical, and chemical properties of porous stainless steel. From the point of view of permeability, specimens made by die extrusion are approximately equivalent to those made by sintering freely-poured atomized powder.3.A method is proposed for the evaluation of

  2. Embrittlement of austenitic stainless steel welds

    Microsoft Academic Search

    S. A. David; J. M. Vitek; D. J. Alexander

    1995-01-01

    To prevent hot-cracking, austenitic stainless steel welds generally contain a small percent of delta ferrite. Although ferrite has been found to effectively prevent hot-cracking, it can lead to embrittlement of welds when exposed to elevated temperatures. The aging behavior of type-308 stainless steel weld has been examined over a range of temperatures 475--850 C for times up to 10,000 hrs.

  3. Solidification cracking in austenitic stainless steel welds

    Microsoft Academic Search

    V. Shankar; T. P. S. Gill; S. L. Mannan; S. Sundaresan

    2003-01-01

    Solidification cracking is a significant problem during the welding of austenitic stainless steels, particularly in fully\\u000a austenitic and stabilized compositions. Hot cracking in stainless steel welds is caused by low-melting eutectics containing\\u000a impurities such as S, P and alloy elements such as Ti, Nb. The WRC-92 diagram can be used as a general guide to maintain a\\u000a desirable solidification mode

  4. Embrittlement of austenitic stainless steel welds

    Microsoft Academic Search

    S. A. David; J. M. Vitek; D. J. Alexander

    1996-01-01

    To prevent hot-cracking, austenitic stainless steel welds generally contain a small percent of delta ferrite. Although ferrite has been found to effectively prevent hot-cracking, it can lead to embrittlement of welds when exposed to elevated temperatures. The aging behavior of type-308 stainless steel weld has been examined over a range of temperatures 400–850‡C for times up to 10,000 hr. Upon

  5. Stress corrosion cracking of duplex stainless steels in caustic solutions

    NASA Astrophysics Data System (ADS)

    Bhattacharya, Ananya

    Duplex stainless steels (DSS) with roughly equal amount of austenite and ferrite phases are being used in industries such as petrochemical, nuclear, pulp and paper mills, de-salination plants, marine environments, and others. However, many DSS grades have been reported to undergo corrosion and stress corrosion cracking in some aggressive environments such as chlorides and sulfide-containing caustic solutions. Although stress corrosion cracking of duplex stainless steels in chloride solution has been investigated and well documented in the literature but the SCC mechanisms for DSS in caustic solutions were not known. Microstructural changes during fabrication processes affect the overall SCC susceptibility of these steels in caustic solutions. Other environmental factors, like pH of the solution, temperature, and resulting electrochemical potential also influence the SCC susceptibility of duplex stainless steels. In this study, the role of material and environmental parameters on corrosion and stress corrosion cracking of duplex stainless steels in caustic solutions were investigated. Changes in the DSS microstructure by different annealing and aging treatments were characterized in terms of changes in the ratio of austenite and ferrite phases, phase morphology and intermetallic precipitation using optical micrography, SEM, EDS, XRD, nano-indentation and microhardness methods. These samples were then tested for general and localized corrosion susceptibility and SCC to understand the underlying mechanisms of crack initiation and propagation in DSS in the above-mentioned environments. Results showed that the austenite phase in the DSS is more susceptible to crack initiation and propagation in caustic solutions, which is different from that in the low pH chloride environment where the ferrite phase is the more susceptible phase. This study also showed that microstructural changes in duplex stainless steels due to different heat treatments could affect their SCC susceptibility. Annealed and water quenched specimens were found to be immune to SCC in caustic environment. Aging treatment at 800°C gave rise to sigma and chi precipitates in the DSS. However, these sigma and chi precipitates, known to initiate cracking in DSS in chloride environment did not cause any cracking of DSS in caustic solutions. Aging of DSS at 475°C had resulted in '475°C embrittlement' and caused cracks to initiate in the ferrite phase. This was in contrast to the cracks initiating in the austenite phase in the as-received DSS. Alloy composition and microstructure of DSS as well as solution composition (dissolved ionic species) was also found to affect the electrochemical behavior and passivation of DSS which in turn plays a major role in stress corrosion crack initiation and propagation. Corrosion rates and SCC susceptibility of DSS was found to increase with addition of sulfide to caustic solutions. Corrosion films on DSS, characterized using XRD and X-ray photoelectron spectroscopy, indicated that the metal sulfide compounds were formed along with oxides at the metal surface in the presence of sulfide containing caustic environments. These metal sulfide containing passive films are unstable and hence breaks down under mechanical straining, leading to SCC initiations. The overall results from this study helped in understanding the mechanism of SCC in caustic solutions. Favorable slip systems in the austenite phase of DSS favors slip-induced local film damage thereby initiating a stress corrosion crack. Repeated film repassivation and breaking, followed by crack tip dissolution results in crack propagation in the austenite phase of DSS alloys. Result from this study will have a significant impact in terms of identifying the alloy compositions, fabrication processes, microstructures, and environmental conditions that may be avoided to mitigate corrosion and stress corrosion cracking of DSS in caustic solutions.

  6. IOP PUBLISHING MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING Modelling Simul. Mater. Sci. Eng. 17 (2009) 075013 (13pp) doi:10.1088/0965-0393/17/7/075013

    E-print Network

    Deymier, Pierre

    2009-01-01

    .iop.org/MSMSE/17/075013 Abstract In this paper, we present a theoretical analysis of the propagation of acoustic calculations of transmission spectra are conducted by extending the finite-difference-time-domain method. Sci. Eng. 17 (2009) 075013 (13pp) doi:10.1088/0965-0393/17/7/075013 Viscoelastic effect on acoustic

  7. Influence of pH on electrochemically deposited CdSe thin films

    Microsoft Academic Search

    S. M. Pawar; A. V. Moholkar; C. H. Bhosale

    2007-01-01

    Polycrystalline CdSe thin films have been electrodeposited at room temperature on stainless steel (ss) and fluorine doped tin oxide (FTO) coated glass substrate from aqueous electrolytes containing salts of cadmium acetate and selenium dioxide. The pH of the bath is varied from 1.75, at the interval of 0.25, to 3. The effect of pH on the photoelectrochemical (PEC), structural and

  8. Electrochemical codeposition of sol-gel films on stainless steel: controlling the chemical and physical coating properties of biomedical implants.

    PubMed

    Okner, Regina; Favaro, Gregory; Radko, Anna; Domb, Abraham Jacob; Mandler, Daniel

    2010-12-14

    The electrochemically assisted codeposition of sol-gel thin films on stainless steel is described. Specifically, electrodeposition of films based on aminopropyltriethoxysilane (APTS), and its codeposition with propyltrimethoxysilane (PrTMOS) and phenyltrimethoxysilane (PhTMOS) has been accomplished by applying negative potentials. The latter increases the concentration of hydroxyl ions on the stainless steel surface and thus catalyzes the condensation and deposition of the sol-gel films. The films were characterized by profilometry, electrochemical impedance spectroscopy (EIS), alternating current voltammetry (ACV), goniometry, atomic force microscopy (AFM) and scanning electron microscopy (SEM). AFM and SEM analysis of codeposited APTS:PrTMOS films disclosed the structural changes induced by altering the deposition solution composition and the applied potential. Codeposited APTS:PhTMOS did not show any structural differences from their electrodeposited homopolymers, while Nano Scratch Test clearly revealed the changes in the elastic and adhesion properties, suggesting the formation of an APTS:PhTMOS composite. EIS of the films showed good resistance towards penetration of hydrophilic species, such as hexacyanoferrate. ACV measurements of the homo and codeposits showed the decrease of the interfacial capacity as a result of the electrochemical deposition. In essence, controllable sol-gel films with tunable chemical and physical properties based on controlling the combination of the precursors, pH and electrochemical properties can be electrodeposited on conducting surfaces. The application of this approach has been demonstrated by coating a stainless steel coronary stent. PMID:20877869

  9. High-Performance Corrosion-Resistant Iron-Based Amorphous Metals - The Effects of Composition, Structure and Environment: Fe49.7Cr17.7Mn1.9Mo7.4W1.6B15.2C3.8Si2.4

    SciTech Connect

    Farmer, J; Haslam, J; Day, S; Lian, T; Saw, C; Hailey, P; Choi, J; Yang, N; Bayles, R; Aprigliano, L; Payer, J; Perepezko, J; Hildal, K; Lavernia, E; Ajdelsztajn, L; Branagan, D J; Beardsely, M B

    2006-10-20

    Several Fe-based amorphous metal formulations have been identified that appear to have corrosion resistance comparable to (or better than) that of Ni-based Alloy C-22 (UNS No. N06022), based on measurements of breakdown potential and corrosion rate in seawater. Both chromium (Cr) and molybdenum (Mo) provide corrosion resistance, boron (B) enables glass formation, and rare earths such as yttrium (Y) lower critical cooling rate (CCR). SAM2X5 (Fe{sub 49.7}Cr{sub 17.7}Mn{sub 1.9}Mo{sub 7.4}W{sub 1.6}B{sub 15.2}C{sub 3.8}Si{sub 2.4}) has no yttrium, and is characterized by relatively high critical cooling rates of approximately 600 Kelvin per second. Data for the SAM2X5 formulation is reported here. In contrast to yttrium-containing iron-based amorphous metals, SAM2X5 can be readily gas atomized to produce spherical powders which enable more facile thermal spray deposition. The reference material, nickel-based Alloy C-22, is an outstanding corrosion-resistant engineering material. Even so, crevice corrosion has been observed with C-22 in hot sodium chloride environments without buffer or inhibitor. SAM2X5 also experiences crevice corrosion under sufficiently harsh conditions. Both Alloy C-22 and Type 316L stainless lose their resistance to corrosion during thermal spraying, due to the formation of deleterious intermetallic phases which depletes the matrix of key alloy elements, whereas SAM2X5 can be applied as coatings with the same corrosion resistance as a fully-dense completely amorphous melt-spun ribbon, provided that its amorphous nature is preserved during thermal spraying. The hardness of Type 316L Stainless Steel is approximately 150 VHN, that of Alloy C-22 is approximately 250 VHN, and that of HVOF SAM2X5 ranges from 1100-1300 VHN [MRS12-13]. Such hardness makes these materials particularly attractive for applications where corrosion-erosion and wear are also issues. Since SAM2X5 has high boron content, it can absorb neutrons efficiently, and may therefore find useful applications as a criticality control material within the nuclear industry.

  10. High Mn austenitic stainless steel

    DOEpatents

    Yamamoto, Yukinori (Oak Ridge, TN) [Oak Ridge, TN; Santella, Michael L (Knoxville, TN) [Knoxville, TN; Brady, Michael P (Oak Ridge, TN) [Oak Ridge, TN; Maziasz, Philip J (Oak Ridge, TN) [Oak Ridge, TN; Liu, Chain-tsuan (Knoxville, TN) [Knoxville, TN

    2010-07-13

    An austenitic stainless steel alloy includes, in weight percent: >4 to 15 Mn; 8 to 15 Ni; 14 to 16 Cr; 2.4 to 3 Al; 0.4 to 1 total of at least one of Nb and Ta; 0.05 to 0.2 C; 0.01 to 0.02 B; no more than 0.3 of combined Ti+V; up to 3 Mo; up to 3 Co; up to 1W; up to 3 Cu; up to 1 Si; up to 0.05 P; up to 1 total of at least one of Y, La, Ce, Hf, and Zr; less than 0.05 N; and base Fe, wherein the weight percent Fe is greater than the weight percent Ni, and wherein the alloy forms an external continuous scale including alumina, nanometer scale sized particles distributed throughout the microstructure, the particles including at least one of NbC and TaC, and a stable essentially single phase FCC austenitic matrix microstructure that is essentially delta-ferrite-free and essentially BCC-phase-free.

  11. A vibrational spectroscopic study of the borate mineral ezcurrite Na4B10O17·7H2O - Implications for the molecular structure

    NASA Astrophysics Data System (ADS)

    Frost, Ray L.; López, Andrés; Theiss, Frederick L.; Scholz, Ricardo; Belotti, Fernanda M.

    2014-07-01

    We have studied the boron containing mineral ezcurrite Na4B10O17·7H2O using electron microscopy and vibrational spectroscopy. Both tetrahedral and trigonal boron units are observed. The nominal resolution of the Raman spectrometer is of the order of 2 cm-1 and as such is sufficient enough to identify separate bands for the stretching bands of the two boron isotopes. The Raman band at 1037 cm-1 is assigned to BO stretching vibration. Raman bands at 1129, 1163, 1193 cm-1 are attributed to BO stretching vibration of the tetrahedral units. The Raman band at 947 cm-1 is attributed to the antisymmetric stretching modes of tetrahedral boron. The sharp Raman peak at 1037 cm-1 is from the 11-B component such a mode, then it should have a smaller 10-B satellite near (1.03) × (1037) = 1048 cm-1, and indeed a small peak at 1048 is observed. The broad Raman bands at 3186, 3329, 3431, 3509, 3547 and 3576 cm-1 are assigned to water stretching vibrations. Broad infrared bands at 3170, 3322, 3419, 3450, 3493, 3542, 3577 and 3597 cm-1 are also assigned to water stretching vibrations. Infrared bands at 1330, 1352, 1389, 1407, 1421 and 1457 cm-1 are assigned to the antisymmetric stretching vibrations of trigonal boron. The observation of so many bands suggests that there is considerable variation in the structure of ezcurrite. Infrared bands at 1634, 1646 and 1681 cm-1 are assigned to water bending modes. The number of water bending modes is in harmony with the number of water stretching vibrations.

  12. Analysis of Stainless Steel Sandwich Panels with a Metal Foam Core for Lightweight Fan Blade Design

    NASA Technical Reports Server (NTRS)

    Min, James B.; Ghosn, Louis J.; Lerch, Bradley A.; Raj, Sai V.; Holland, Frederic A., Jr.; Hebsur, Mohan G.

    2004-01-01

    The quest for cheap, low density and high performance materials in the design of aircraft and rotorcraft engine fan and propeller blades poses immense challenges to the materials and structural design engineers. The present study investigates the use of a sandwich foam fan blade mae up of solid face sheets and a metal foam core. The face sheets and the metal foam core material were an aerospace grade precipitation hardened 17-4 PH stainless steel with high strength and high toughness. The resulting structures possesses a high stiffness while being lighter than a similar solid construction. The material properties of 17-4 PH metal foam are reviewed briefly to describe the characteristics of sandwich structure for a fan blade application. A vibration analysis for natural frequencies and a detailed stress analysis on the 17-4 PH sandwich foam blade design for different combinations of kin thickness and core volume are presented with a comparison to a solid titanium blade.

  13. Localized corrosion and stress corrosion cracking behavior of austenitic stainless steel weldments containing retained ferrite. Annual progress report, June 1, 1977March 31, 1978

    Microsoft Academic Search

    W. F. Savage; D. J. Duquette

    1978-01-01

    Localized corrosion (pitting) experiments have been performed on single-phase austenitic 304 stainless steels and on duplex 304 steels containing 6 to 8% retained delta ferrite as a result of rapid solidification (welding). Experimental variables included thermomechanical treatment, solution pH, chloride concentration and solution temperature.

  14. Characterization and perspective of stress corrosion cracking of austenitic stainless steels (type 304 and type 316) in acid solutions using constant load method

    Microsoft Academic Search

    Rokuro Nishimura

    2007-01-01

    The stress corrosion cracking (SCC) of the commercial austenitic stainless steels, type 304 and type 316 has been extensively investigated as functions of applied stress, sensitizing temperature, sensitizing time and the environmental factors such as pH, anion concentration, anion species (chloride ions and sulfate ions), test temperature, applied potential and inhibitor concentrations of chromate and molybdate by using a constant

  15. Electrochemical characterization of AISI 316L stainless steel in contact with simulated body fluid under infection conditions.

    PubMed

    López, Danián Alejandro; Durán, Alicia; Ceré, Silvia Marcela

    2008-05-01

    Titanium and cobalt alloys, as well as some stainless steels, are among the most frequently used materials in orthopaedic surgery. In industrialized countries, stainless steel devices are used only for temporary implants due to their lower corrosion resistance in physiologic media when compared to other alloys. However, due to economical reasons, the use of stainless steel alloys for permanent implants is very common in developing countries. The implantation of foreign bodies is sometimes necessary in the modern medical practice. However, the complex interactions between the host and the can implant weaken the local immune system, increasing the risk of infections. Therefore, it is necessary to further study these materials as well as the characteristics of the superficial film formed in physiologic media in infection conditions in order to control their potential toxicity due to the release of metallic ions in the human body. This work presents a study of the superficial composition and the corrosion resistance of AISI 316L stainless steel and the influence of its main alloying elements when they are exposed to an acidic solution that simulates the change of pH that occurs when an infection develops. Aerated simulated body fluid (SBF) was employed as working solution at 37 degrees C. The pH was adjusted to 7.25 and 4 in order to reproduce normal body and disease state respectively. Corrosion resistance was measured by means of electrochemical impedance spectroscopy (EIS) and anodic polarization curves. PMID:17999036

  16. Superplastic forming of stainless steel automotive components

    SciTech Connect

    Bridges, B. [Lockheed Martin Energy Systems, Inc., Oak Ridge, TN (United States); Elmer, J. [Lawrence Livermore National Lab., CA (United States); Carol, L. [AC Delco Systems World Headquarters, Flint, MI (United States). USCAR Low Emissions Technology Research and Development Partnership

    1997-02-06

    Exhaust emission standards are governmentally controlled standards, which are increasingly stringent, forcing alternate strategies to meet these standards. One approach to improve the efficiency of the exhaust emission equipment is to decrease the time required to get the catalytic converter to optimum operating temperature. To accomplish this, automotive manufacturers are using double wall stainless steel exhaust manifolds to reduce heat loss of the exhaust gases to the converter. The current method to manufacture double wall stainless steel exhaust components is to use a low-cost alloy with good forming properties and extensively form, cut, assemble, and weld the pieces. Superplastic forming (SPF) technology along with alloy improvements has potential at making this process more cost effective. Lockheed Martin Energy Systems (LMES), Lawrence Livermore National Laboratory (LLNL) and USCAR Low Emission Partnership (LEP) worked under a Cooperative Research And Development Agreement (CRADA) to evaluate material properties, SPF behavior, and welding behavior of duplex stainless steel alloy for automotive component manufacturing. Battelle Pacific Northwest National Laboratory (PNNL) has a separate CRADA with the LEP to use SPF technology to manufacture a double wall stainless steel exhaust component. As a team these CRADAs developed and demonstrated a technical plan to accomplish making double wall stainless steel exhaust manifolds.

  17. Quantification of phase transformation in stainless steel 301LN sheets

    E-print Network

    Beese, Allison M

    2008-01-01

    This thesis investigates the large deformation behavior of stainless steel 301LN cold-rolled sheets which is largely governed by the initial anisotropy combined with the phase transformation during deformation. Stainless ...

  18. Casting Stainless-Steel Models Around Pressure Tubes

    NASA Technical Reports Server (NTRS)

    Vasquez, Peter; Micol, John R.

    1992-01-01

    Survivability of thin-wall stainless-steel tubing increased to nearly 100 percent. Improves state of art in pressure-model castings and reduces cost associated with machining complete model from stainless-steel blank.

  19. Stress corrosion cracking of type 321 stainless steels in simulated petrochemical process environments containing hydrogen sulfide and chloride

    Microsoft Academic Search

    Y. Y. Chen; Y. M. Liou; H. C. Shih

    2005-01-01

    The susceptibility to stress corrosion cracking (SCC) of type 321 stainless steel (type 321s) in a simulated petrochemical process environment containing hydrogen sulfide and chloride (20wt.% NaCl+0.01M Na2S2O3, pH 2) was assessed using the slow strain rate tensile (SSRT) test and static load (U-bend) tests at the free corrosion potentials. In the SSRT, effects of environmental factors, such as chloride

  20. The improvement of the corrosion resistance of 309 stainless steel in the transpassive region by nano-crystallization

    Microsoft Academic Search

    Wei Ye; Ying Li; Fuhui Wang

    2009-01-01

    The effect of nano-crystallization on the corrosion behavior of 309 stainless steel in the transpassive region was investigated in 0.5M Na2SO4 (pH 2) solution. Three parts defined as transpassive dissolution, secondary passivity and oxygen evolution can be observed in the transpassive potential region of the anodic polarization curves. In the whole transpassive region the nano-crystalline coating has a smaller corrosion

  1. Hydrogen-assisted cracking in a precipitation-hardened stainless steel: effects of heat treatment and displacement rate

    Microsoft Academic Search

    L. M. Young; M. R. Eggleston; H. D. Solomon; L. R. Kaisand

    1995-01-01

    The hydrogen embrittlement susceptibility of PH 13-8 Mo stainless steel was evaluated using non-linear fracture mechanics methods. The initiation toughness, Ji, and the resistance to stable crack growth, dJ\\/da, were measured using precracked compact specimens. Specimens were electrochemically charged with hydrogen prior to fracture testing in air. After charging, a monotonically increasing load-line displacement was applied to produce the J-integral

  2. Understanding pH

    NSDL National Science Digital Library

    Brieske, Joel A.

    The first site related to pH is from the Horiba corporate Web site entitled the Story of pH (1). Visitors can learn what pH is and how it's measured, explore various facts about pH, and read several anecdotes such as "Is the Rain in Our Cities Acidic." The site contains simple text, attractive graphics, and a well-designed layout making it fun and easy for anyone to explore. The second site from the Miami Museum of Science is called the pH Factor (2) kids activity page. This interactive and extensive site contains lessons on testing items for pH, tasting acids and bases, an interactive meter to find the pH of common household items, and much more. Next, is the pH and Water Quality (3) page, which is part of the State of Kentucky Division of Water Web site. The site provides a table of the effects of pH on fish and aquatic life and gives a short description of the most significant environmental impacts of pH. Trout for example, can tolerate a pH range between 4.1 and 9.5 while Mosquito larvae can survive within the 3.3 and 4.7 range. The fourth site from Gardengate Magazine.com is entitled More Soil Stuff: Soil pH (4). Described is the pH range of most soil types, requirements of certain plants, how to test soil for pH, and how to adjust it using sulfur and limestone. Seaworld.org maintains the Understanding the pH Cycle within the Aquarium (5) lesson plan site. The stated objective of the activity is to have students define pH, explain how it affects a tank's water quality, and test the pH level in a classroom aquarium. Although an aquarium is obviously needed, the activity offers a unique and fun way for kids to learn about this basic chemistry concept. About.com offers the next site, which is an interactive pH calculator called pH (6). Users simply enter a pH to get the concentration of Hydrogen ions or, conversely, the Hydrogen ion concentration to get the pH. Another tool to learn about pH and Hydrogen ions is called Acids and Alkalis--the pH Scale (7). Provided by Purchon.com, the interactive pH scale illustrates how the ion concentration changes with pH, common acids associated with each, and whether it is a weak or strong acid or alkali. The last site maintained by the National Park Service is called Acid Rain Lesson Plan: Activity 1 The pH Scale (8). Kids will be able to describe the pH scale and its components, explain why a pH measurement must be accurate, and explain why small changes in pH are important. Everything needed to complete the activity is provided, including a materials list, complete instructions, thinking questions, as well as links for further information.

  3. Electrodissolution studies of 304 stainless steel in sodium nitrate electrolyte

    SciTech Connect

    Weisbrod, K.R.; Trujillo, V.L.; Martinez, H.E.

    1997-12-01

    To explore the impact of a wide range of operating parameters upon 304 stainless steel (SS) dissolution in sodium nitrate (NaNO{sub 3}) electrolyte, the staff of Engineering Science Applications-Energy and Process Engineering performed a series of beaker experiments. The variables that the authors explored included NaNO{sub 3} concentration, chromate concentration, pH, stirring rate, and current density. They adjusted the run length to obtain approximately 10 mg/cm{sup 2} metal removal so that they could compare surface finishes under similar test conditions. Key findings may be summarized as follows. Current efficiency during dissolution depends most strongly upon current density and electrolyte concentration. At 0.05 A/cm{sup 2}, current density is more dependent upon chromium concentration than they previously thought. They obtained the best surface finish in a classical electropolishing regime at current densities above 1.5 A/cm{sup 2}. Mirror-like finishes were obtained at near 100% current efficiency. At 0.05 a/cm{sup 2} they obtained reasonable surface finishes, particularly at lower electrolyte concentration. Current efficiency was low (30%). At intermediate current densities, they obtained the worst surface finishes, that is, surfaces with severe pitting. Also, they explored preferential attack of the weld zone during electrodissolution of 304 stainless steel cans. Electrodissolution removed approximately twice as much material from cans with unshielded weld zones as from cans with shielded weld zones. The following implications are apparent. While operation above 1 A/cm{sup 2} yields the best surface finish at 100% current efficiency, equipment size and power feedthrough limitations reduce the attractiveness of this option. Because other Los Alamos researchers, obtained more favorable results with the sulfate electrolyte, the authors recommend no further work for the sodium nitrate electrolyte system.

  4. Embrittlement of austenitic stainless steel welds

    SciTech Connect

    David, S.A.; Vitek, J.M.; Alexander, D.J.

    1995-06-01

    To prevent hot-cracking, austenitic stainless steel welds generally contain a small percent of delta ferrite. Although ferrite has been found to effectively prevent hot-cracking, it can lead to embrittlement of welds when exposed to elevated temperatures. The aging behavior of type-308 stainless steel weld has been examined over a range of temperatures 475--850 C for times up to 10,000 hrs. Upon aging, and depending on the temperature range, the unstable ferrite may undergo a variety of solid state transformations. These phase changes creep-rupture and Charpy impact properties.

  5. Ultralight Stainless Steel Urban Bus Concept

    SciTech Connect

    J. Bruce Emmons; Leonard J. Blessing

    2001-05-14

    While stainless steel buses are certainly not new, this study reveals opportunities for substantial improvements in structural performance.The objective of this project was to investigate the mass saving potential of ultra-high strength stainless steel as applied to the structure of a full size urban transit bus.The resulting design for a low floor,hybrid bus has an empty weight less than half that of a conventional transit bus.The reduced curb weight allows for a greater payload,without exceeding legal axle limits. A combination of finite element modeling and dynamic testing of scale models was used to predict structural performance.

  6. Characteristics of VHF radiowave scintillations over a solar cycle (1983-1993) at a low-latitude station: Waltair (17.7 deg N, 83.3 deg E)

    Microsoft Academic Search

    P. V. S. Rama Rao; P. T. Jayachandran; P. Sri Ram; B. V. Ramana Rao; D. S. V. V. D. Prasad; K. K. Bose

    1997-01-01

    The characteristics of VHF radiowave scintillations at 244 MHz (FLEETSAT) during a complete solar cycle (1983-93) at a low-latitude station, Waltair (17.7 deg N, 83.3 deg E), are presented. The occurrence of night-time scintillations shows equinoctial maxima and summer minima in all the epochs of solar activity, and follows the solar activity. The daytime scintillation occurrence is negatively correlated with

  7. Monday Tuesday Wednesday Thursday Friday PH 1110 PH 1110

    E-print Network

    Weekes, Suzanne L.

    Monday Tuesday Wednesday Thursday Friday PH 1110 PH 1110 Muhammad Muhammad CS 1101 CS 1101 CS 1101 Mairaj Mairaj Mairaj Ph 1111 Ph 1111 PH 1111 Zhen Zhen Zhen CH 1010 CH 1010 Elisabeth Elisabeth MA 1023 MA 1021 MA 1023 MA 1021 Kushi Han Li Murtaza Jeffrey MA 1021 MA 1023 PH 1110 Han Li Murtaza Muhammad

  8. Study of passive films formed on AISI 304 stainless steel by impedance measurements and photoelectrochemistry

    SciTech Connect

    Simoes, A.M.P.; Ferreiro, M.G.S. (Dept. de Engenharia Quimica, Instituto Superior Tecnico, 1096 Lisboa Codex (PT)); Rondot, B.; Belo, M. (Centre National de la Recherche Scientifique, 94 - Vitry-sur-Seine (France). Centre d'Etudes de Chimie Metallurgique)

    1990-01-01

    Moss-Schottky plots and photoelectrochemical measurements were made on films formed at different potentials on AISI 304 stainless steel in a borate/boric acid solution, pH 9.2. The results allowed the determination of the semiconductive properties and band structure of the films, which account for the existence of two kinds of films depending on the formation potential. For potentials below 0 V (SCE), the results point out for a film with an inverse spinel structure constituted by Cr-substituted magnetite with two donor levels. Above 0 V only one donor level is detected, which should be Fe{sup 2 +} on tetrahedral sites.

  9. Materials data handbook: Stainless steel type 301

    NASA Technical Reports Server (NTRS)

    Muraca, R. F.; Whittick, J. S.

    1972-01-01

    A summary of the materials property information for stainless steel type 301 is presented. The scope of the information includes physical and mechanical properties at cryogenic, ambient, and elevated temperatures. Information on material procurement, metallurgy of the alloy, corrosion, environmental effects, fabrication, and bonding is developed.

  10. Stainless Steel for Accelerated Bridge Construction

    Microsoft Academic Search

    F. B. Fletcher; A. D. Wilson; J. Strasky; J. N. Kilpatrick; J. S. Wrysinski

    ASTM A1010 is a 12% chromium stainless plate steel used in corrosive structural applications because of its superior performance when compared to weathering or galvanized steels. A1010 can be produced at 50 ksi minimum yield strengths to 4 inches thick and to 70 ksi to 2.5 inches thick. Recent production properties and corrosion results will be reviewed. The first use

  11. Materials data handbooks on stainless steels

    NASA Technical Reports Server (NTRS)

    Muraca, R. F.; Whittick, J. S.

    1973-01-01

    Two handbooks which summarize latest available data have been published. Two types of stainless steels, alloy A-286 and Type 301, are described. Each handbook is divided into twelve chapters. Scope of information presented includes physical- and mechanical-property data at cryogenic, ambient, and elevated temperatures.

  12. Forming "dynamic" membranes on stainless steel

    NASA Technical Reports Server (NTRS)

    Brandon, C. A.; Gaddis, J. L.

    1979-01-01

    "Dynamic" zirconium polyacrylic membrane is formed directly on stainless steel substrate without excessive corrosion of steel. Membrane is potentially useful in removal of contaminated chemicals from solution through reversed osmosis. Application includes use in filtration and desalination equipment, and in textile industry for separation of dyes from aqueous solvents.

  13. Proof Testing Of Stainless-Steel Bolts

    NASA Technical Reports Server (NTRS)

    Hsieh, Cheng H.; Hendrickson, James A.; Bamford, Robert M.

    1992-01-01

    Report describes study of development of method for nondestructive proof testing of bolts made of A286 stainless steel. Based on concept that the higher load bolt survives, the smaller the largest flaw and, therefore, the longer its fatigue life after test. Calculations and experiments increase confidence in nondestructive proof tests.

  14. Stress corrosion cracking of stainless steels

    Microsoft Academic Search

    R. F. Hehemann

    1985-01-01

    The similarities and differences in the stress corrosion cracking response of ferritic and austenitic stainless steels in chloride solutions will be examined. Both classes of materials exhibit a cracking potential: similar transient response (to loading) of the potential in open circuit tests or the current in potentiostatic tests and similar enrichment of chromium and depletion of iron in the film

  15. Precipitate formation in austenitic stainless steel welds

    Microsoft Academic Search

    M. J. Cieslak; A. M. Ritter

    1985-01-01

    Recent research efforts have revealed many of the factors which control the hotcracking susceptibility of austenitic stainless steel weld metals. It is generally agreed that the segregation of impurity elements to solidification grain boundaries is a primary cause of the hot-cracking tendency of these alloys in that elements such as phosphorus and sulfur form low melting point eutectics with the

  16. Sintered Cu Alloyed Stainless Steels and Their Corrosion Behavior

    NASA Astrophysics Data System (ADS)

    Wang, Jun'an; He, Ying; He, Peng; Zhou, Bangxin

    2008-10-01

    Copper is an effective element to activate the sintering process of stainless steels and to enhance corrosion resistance of the sintered specimens. Ways of introducing Cu into stainless steel powders lead to different consequence in the microstructure and corrosion behavior of sintered Cu alloyed stainless steel. In the present work, two methods, mixing Cu with stainless steel powder and coating stainless steel powder with Cu by electroless plating, were introduced in order to investigate their influence on the sintered specimens. It was found that the sintered specimens from Cu-coated stainless steel powders (1-5 wt.%Cu) produce less porous surfaces with isolated pores than the specimens from mixed powders and the former have obviously high density and relatively even Cu distribution. Potentiodynamic polarization measurements indicate that Cu-electroless plating of 1-5 wt.%Cu improves the corrosion resistance of sintered stainless steel due to the lowering of passivation current density.

  17. Silicon strain gages bonded on stainless steel using glass frit for strain sensor applications

    NASA Astrophysics Data System (ADS)

    Zhang, Zongyang; Cheng, Xingguo; Leng, Yi; Cao, Gang; Liu, Sheng

    2014-05-01

    In this paper, a steel pressure sensor using strain gages bonded on a 17-4 PH stainless steel (SS) diaphragm based on glass frit technology is proposed. The strain gages with uniform resistance are obtained by growing an epi-silicon layer on a single crystal silicon wafer using epitaxial deposition technique. The inorganic glass frits are used as the bonding material between the strain gages and the 17-4 PH SS diaphragm. Our results show that the output performances of sensors at a high temperature of 125 °C are almost equal those at room temperature, which indicates that the glass frit bonding is a good method and may lead to a significant advance in the high temperature applicability of silicon strain gage sensors. Finally, the microstructure of the cured organic adhesive and the fired glass frit are compared. It may be concluded that the defects of the cured organic adhesive deteriorate the hysteresis and repeatability errors of the sensors.

  18. pH Game

    NSDL National Science Digital Library

    The GLOBE Program, UCAR (University Corporation for Atmospheric Research)

    2003-08-01

    The purpose of this resource is to teach students about the acidity levels of liquids and other substances around their school so they understand what pH levels tell us about the environment. Students will create mixtures of water samples, soil samples, plants and other natural materials to better understand the importance of pH levels.

  19. Comparison of stainless steels in simulated paper machine environments

    SciTech Connect

    Laitinen, T.M.J. [VTT Manufacturing Technology (Finland)

    1999-09-01

    The localized corrosion behavior of austenitic stainless steels (SS) UNS S30403 and UNS S31603, and duplex SS UNS S31803 was compared in simulated paper machine environments containing chloride, sulfate, and thiosulfate at pH 3 and 65 C. Electrochemical testing of the materials was performed by cyclic polarization scans and scratch tests. Thiosulfate caused a remarkable decrease in repassivation potentials (E{sub pp}) and a slight decrease in pitting potentials (E{sub np}) of UNS S30403 and UNS S31603, when compared to the corresponding E{sub pp} and E{sub np} values determined in similar solutions without thiosulfate addition. Pits on UNS S30403 and UNS S31603 steels were enriched in Cr and Cu and depleted in Fe when compared to the base metal. Thiosulfate being present in the solution pits contained also very high amounts of S. Thiosulfate was proposed to be reduced to hydrogen sulfide (H{sub 2}S) inside the pits enhancing the anodic dissolution process of SS. In the case of UNS S31803, test environments had hardly any influence on the determined high E{sub pp} and E{sub np} values. Chloride concentration had to be a minimum of 500 mg/L until any localized corrosion could be observed on UNS S31803.

  20. Chromium and nickel aerosols in stainless steel manufacturing, grinding and welding

    Microsoft Academic Search

    MATTI KOPONEN; TOM GUSTAFSSON; PIRKKO-LIISA KALLIOMÄKI; LAURI PYY

    1981-01-01

    Composition, morphology and solubility of chromium and nickel in fumes from stainless steel manufacturing, based on ferrochrome, and in dusts from grinding of stainless steel, were studied. The results were compared with corresponding analyses of stainless steel welding fumes. In fumes from the melting of ferrochrome and stainless steel, as well as in dusts from the grinding of stainless steel,

  1. Formability of type 304 stainless steel sheet

    SciTech Connect

    Coubrough, G.J. (EG and G Rocky Flats, Inc., Golden, CO (United States). Rocky Flats Plant); Matlock, D.K.; VanTyne, C.J. (Colorado School of Mines, Golden, CO (United States))

    1992-01-01

    Punch-stretch tests to determine formability of type 304 stainless steel sheet were conducted using a hemispherical dome test. Sheets of 19.1 mm width and 177.8 mm width were stretched on a 101.6 mm diameter punch at punch rates between 0.042 to 2.12 mm/s with three lubricant systems: a mineral seal oil, thin polytetrafluoroethelyne sheet with mineral seal oil, and silicone rubber with mineral seal oil. The resulting strain distributions were measured and the amount of martensite was determined by magnetic means. Increasing lubricity resulted in more uniform strain distributions while increased punch rates tended to decrease both strain and transformation distributions. High forming limit values were related to the formation of high and uniformly distributed martensite volume fractions during deformation. The results of this study are interpreted with an analysis of the effects of strain and temperature on strain induced martensite formation in metastable austenitic stainless steels.

  2. Formability of type 304 stainless steel sheet

    SciTech Connect

    Coubrough, G.J. [EG and G Rocky Flats, Inc., Golden, CO (United States). Rocky Flats Plant; Matlock, D.K.; VanTyne, C.J. [Colorado School of Mines, Golden, CO (United States)

    1992-09-01

    Punch-stretch tests to determine formability of type 304 stainless steel sheet were conducted using a hemispherical dome test. Sheets of 19.1 mm width and 177.8 mm width were stretched on a 101.6 mm diameter punch at punch rates between 0.042 to 2.12 mm/s with three lubricant systems: a mineral seal oil, thin polytetrafluoroethelyne sheet with mineral seal oil, and silicone rubber with mineral seal oil. The resulting strain distributions were measured and the amount of martensite was determined by magnetic means. Increasing lubricity resulted in more uniform strain distributions while increased punch rates tended to decrease both strain and transformation distributions. High forming limit values were related to the formation of high and uniformly distributed martensite volume fractions during deformation. The results of this study are interpreted with an analysis of the effects of strain and temperature on strain induced martensite formation in metastable austenitic stainless steels.

  3. Formability of type 304 stainless steel sheet

    Microsoft Academic Search

    G. J. Coubrough; D. K. Matlock; C. J. VanTyne

    1992-01-01

    Punch-stretch tests to determine formability of type 304 stainless steel sheet were conducted using a hemispherical dome test. Sheets of 19.1 mm width and 177.8 mm width were stretched on a 101.6 mm diameter punch at punch rates between 0.042 to 2.12 mm\\/s with three lubricant systems: a mineral seal oil, thin polytetrafluoroethelyne sheet with mineral seal oil, and silicone

  4. Fracture toughness of stainless steel welds

    Microsoft Academic Search

    1985-01-01

    The effects of temperature, composition and weld-process variations on the fracture toughness behavior for Types 308 and 16-8-2 stainless steel (SS) welds were examined using the multiple-specimen J\\/sub R\\/-curve procedure. Fracture characteristics were found to be dependent on temperature and weld process but not on filler material. Gas-tungsten-arc (GTA) welds exhibited the highest fracture toughness, a shielded metal-arc (SMA) weld

  5. THE CLEANING OF 303 STAINLESS STEEL

    Microsoft Academic Search

    Shen

    2004-01-01

    The sulfur found on the surfaces of stainless steel 303 (SS303) after nitric acid passivation originated from the MnS inclusions in the steel. The nitric acid attacked and dissolved these MnS inclusions, and redeposited micron-sized elemental sulfur particles back to the surface. To develop an alternative passivation procedure for SS303, citric and phosphoric acids have been evaluated. The experimental results

  6. Introduction to stainless steels, 3. edition

    SciTech Connect

    Beddoes, J.; Parr, J.G.

    1999-01-01

    Designed as a basic and introductory reference, this book not only addresses stainless steels in the light of their resistance to corrosion for which they are more commonly recognized but also explains the wide range of other useful properties attributable to the various and specific categories of these alloys. First published in 1965 and updated in 1986, this third edition is a completely new text.

  7. Stress corrosion cracking of stainless steels

    Microsoft Academic Search

    R. F. Hehemann

    1985-01-01

    The similarities and differences in the stress corrosion cracking response of ferritic and austenitic stainless steels in\\u000a chloride solutions will be examined. Both classes of materials exhibit a cracking potential: similar transient response (to\\u000a loading) of the potential in open circuit tests or the current in potentiostatic tests and similar enrichment of chromium\\u000a and depletion of iron in the film

  8. Partial replacement of chromium in stainless steel

    Microsoft Academic Search

    M. L. Glenn; S. J. Bullard; D. E. Larson; S. C. Rhoads

    1985-01-01

    The Bureau of Mines, U.S. Department of the Interior, conducted research on the partial replacement of chromium in stainless\\u000a steel. The alloys examined contain 8 to 9 pct Cr, 11 to 14 pct Ni, and additions of up to 5 pct Mo, 2 pct Cu, and 2 pct V\\u000a for corrosion-resistant applications and up to 5 pct Si and 2

  9. Creep of austenitic stainless steel welds

    Microsoft Academic Search

    S L Mannan; M D Mathew

    1996-01-01

    Austenitic stainless steels (SS) find extensive application in power, petrochemical and nuclear industries in view of their\\u000a excellent elevated temperature mechanical properties, corrosion resistance, formability and weldability. However, they are\\u000a susceptible to hot cracking during fusion welding. To avoid this problem, chemical composition of the welding consumable is\\u000a generally adjusted to promote primary ferrite mode of solidification and retain about

  10. Model to Study the Effect of Composition of Seawater on the Corrosion Rate of Mild Steel and Stainless Steel

    NASA Astrophysics Data System (ADS)

    Paul, Subir

    2011-04-01

    Mild steel and 304 stainless steel are the versatile materials of construction for various structures in ocean water, whose composition varies widely in the vast global marine environment. The major parameters influencing the rate are salinity, sulfate, bicarbonates, pH, and temperature and dissolved oxygen. Prediction of the rate of degradation is a challenging task for design and corrosion engineers for existing as well as new structures to be constructed. Endeavors have been made to model the corrosion rate of mild steel and 304 stainless steel as function of five parameters, namely chloride, sulfate, dissolved oxygen, pH, and temperature, based on laboratory experimental data. The number of experimentations and compositions of experimental artificial seawater were based on 2 k factorial design of experiment. The model was validated with additional generated experimental data as well as real field study from the literature. Three-dimensional mappings of corrosion behavior of mild steel and stainless steel reveal that the effects of these parameters are interrelated and influenced by one another.

  11. Impact Testing of Stainless Steel Materials

    SciTech Connect

    R. K. Blandford; D. K. Morton; T. E. Rahl; S. D. Snow

    2005-07-01

    Stainless steels are used for the construction of numerous spent nuclear fuel or radioactive material containers that may be subjected to high strains and moderate strain rates (10 to 200 per second) during accidental drop events. Mechanical characteristics of these materials under dynamic (impact) loads in the strain rate range of concern are not well documented. The goal of the work presented in this paper was to improve understanding of moderate strain rate phenomena on these materials. Utilizing a drop-weight impact test machine and relatively large test specimens (1/2-inch thick), initial test efforts focused on the tensile behavior of specific stainless steel materials during impact loading. Impact tests of 304L and 316L stainless steel test specimens at two different strain rates, 25 per second (304L and 316L material) and 50 per second (304L material) were performed for comparison to their quasi-static tensile test properties. Elevated strain rate stress-strain curves for the two materials were determined using the impact test machine and a “total impact energy” approach. This approach considered the deformation energy required to strain the specimens at a given strain rate. The material data developed was then utilized in analytical simulations to validate the final elevated stress-strain curves. The procedures used during testing and the results obtained are described in this paper.

  12. Cast Stainless Steel Ferrite and Grain Structure

    SciTech Connect

    Ruud, Clayton O.; Ramuhalli, Pradeep; Meyer, Ryan M.; Mathews, Royce; Diaz, Aaron A.; Anderson, Michael T.

    2012-09-01

    In-service inspection requirements dictate that piping welds in the primary pressure boundary of light-water reactors be subject to a volumetric examination based on the rules contained within the American Society of Mechanical Engineers Boiler and Pressure Vessel Code, Section XI. The purpose of the inspection is the reliable detection and accurate sizing of service-induced degradation and/or material flaws introduced during fabrication. The volumetric inspection is usually carried out using ultrasonic testing (UT) methods. However, the varied metallurgical macrostructures and microstructures of cast austenitic stainless steel piping and fittings, including statically cast stainless steel and centrifugally cast stainless steel (CCSS), introduce significant variations in the propagation and attenuation of ultrasonic energy. These variations complicate interpretation of the UT responses and may compromise the reliability of UT inspection. A review of the literature indicated that a correlation may exist between the microstructure and the delta ferrite content of the casting alloy. This paper discusses the results of a recent study where the goal was to determine if a correlation existed between measured and/or calculated ferrite content and grain structure in CCSS pipe.

  13. Positron annihilation lifetime measurement of irradiated stainless steels

    NASA Astrophysics Data System (ADS)

    Kuramoto, E.; Tsukuda, N.; Aono, Y.; Takenaka, M.; Takano, Y.; Yoshida, H.; Shiraishi, K.

    1985-08-01

    Two types of austenitic stainless steels (316SS and JPCA) and two types of ferritic/martensitic stainless steels (HT-9 and JFMS) were irradiated by high energy electrons at 77 K and positron annihilation lifetime measurements were carried out to obtain the isochronal annealing behaviour above room temperature. The main decrease of the intensity of the second component, namely, the migration of vacancies to sinks was observed at 250°C for austenitic stainless steels and at 150°C for ferritic/martensitic stainless steels. By assuming the number of jumps to sinks as 10 3, the vacancy migration energy was obtained as 1.36 and 1.10 eV for austenitic and ferritic/martensitic stainless steels, respectively. This result was used to discuss the low swelling behaviour of the ferritic/martensitic stainless steels.

  14. Decontaminating and Melt Recycling Tritium Contaminated Stainless Steel

    SciTech Connect

    Clark, E.A.

    1995-04-03

    The Westinghouse Savannah River Company, Idaho National Engineering Laboratory, and several university and industrial partners are evaluating recycling radioactively contaminated stainless steel. The goal of this program is to recycle contaminated stainless steel scrap from US Department of Energy national defense facilities. There is a large quantity of stainless steel at the DOE Savannah River Site from retired heavy water moderated Nuclear material production reactors (for example heat exchangers and process water piping), that will be used in pilot studies of potential recycle processes. These parts are contaminated by fission products, activated species, and tritium generated by neutron irradiation of the primary reactor coolant, which is heavy (deuterated) water. This report reviews current understanding of tritium contamination of stainless steel and previous studies of decontaminating tritium exposed stainless steel. It also outlines stainless steel refining methods, and proposes recommendations based on this review.

  15. Mouse inflammatory response to stainless steel corrosion products

    Microsoft Academic Search

    R. B. Tracana; J. P. Sousa; G. S. Carvalho

    1994-01-01

    Corrosion occurs regularly following long-term implantation of stainless steel. Little is known about the inflammatory and immunological potential of stainless steel corrosion products. AISI 316L stainless steel was anodically dissolved in a physiologically solution, HBSS, through a chronoamperometric process by imposing an external constant current of 0.5 mA. The solution, containing 245 µg of Fe, 112 µg of Cr, 75

  16. Fatigue behavior of Austenitic Type 316L Stainless Steel

    NASA Astrophysics Data System (ADS)

    Mohammad, K. A.; Ali, Aidy; Sahari, B. B.; Abdullah, S.

    2012-09-01

    The aim of this work is to determine the fatigue life of 316L stainless steel. The mechanisms of fatigue of 316L stainless steels were investigated and discussed. The fatigue tests were carried out at constant-amplitude cyclic loading with load ratio R=0.1. Scanning Electron Microscope (SEM) is then used to examine the fracture surface. The results show that the fatigue limit of 316L stainless steel was 146.45 MPa.

  17. Evaluation of filler metals for high-strength stainless steels

    Microsoft Academic Search

    R. W. Swindeman; G. M. Goodwin; J. F. King; C. D. Lundin; C. Y. P. Qiao

    1991-01-01

    Weldments were produced in types 316, 17-14CuMo, and high strength 14Cr-16Ni-2Mo stainless steel base metals with four filler metals-alloy 82, 17-14CuMo stainless steel, controlled residual element CRE 16-8-2 stainless steel, and alloy 556. The welds were evaluated on the basis of microstructure, strength, and ductility. All of the base metals were prone to hot cracking, but steels high in phosphorus

  18. Stainless Steel Leaches Nickel and Chromium into Foods During Cooking

    PubMed Central

    Kamerud, Kristin L.; Hobbie, Kevin A.; Anderson, Kim A.

    2014-01-01

    Toxicological studies show that oral doses of nickel and chromium can cause cutaneous adverse reactions such as dermatitis. Additional dietary sources, such as leaching from stainless steel cookware during food preparation, are not well characterized. This study examined stainless steel grades, cooking time, repetitive cooking cycles, and multiple types of tomato sauces for their effects on nickel and chromium leaching. Trials included three types of stainless steels and a stainless steel saucepan; cooking times of 2 to 20 hours, ten consecutive cooking cycles, and four commercial tomato sauces. After a simulated cooking process, samples were analyzed by ICP-MS for Ni and Cr. After six hours of cooking, Ni and Cr concentrations in tomato sauce increased up to 26- and 7-fold respectively, depending on the grade of stainless steel. Longer cooking durations resulted in additional increases in metal leaching, where Ni concentrations increased 34 fold and Cr increased approximately 35 fold from sauces cooked without stainless steel. Cooking with new stainless steel resulted in the largest increases. Metal leaching decreases with sequential cooking cycles and stabilized after the sixth cooking cycle, though significant metal contributions to foods were still observed. The tenth cooking cycle, resulted in an average of 88 ?g of Ni and 86 ?g of Cr leached per 126 g serving of tomato sauce. Stainless steel cookware can be an overlooked source of nickel and chromium, where the contribution is dependent on stainless steel grade, cooking time, and cookware usage. PMID:23984718

  19. 78 FR 7395 - Stainless Steel Bar From India: Preliminary Results of Antidumping Duty Administrative Review...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-01

    ...the antidumping duty order on stainless steel bar (SSB) from India...Duty Administrative Review: Stainless Steel Bar from India'' dated...Industries LLC, and Valbruna Slater Stainless, Inc., (collectively...Pursuant to 19 CFR 351.309(c), interested...

  20. 77 FR 27815 - Aging Management of Stainless Steel Structures and Components in Treated Borated Water

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-11

    ...aging management of stainless steel structures and components exposed...aging management of stainless steel structures and components exposed...guidance inappropriately credits boron as a corrosion inhibitor in...material and cracking of stainless steel structures and components...

  1. 76 FR 69292 - Aging Management of Stainless Steel Structures and Components in Treated Borated Water

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-08

    ...aging management of stainless steel structures and components exposed...aging management of stainless steel structures and components exposed...guidance inappropriately credits boron as a corrosion inhibitor in...material and cracking of stainless steel structures and components...

  2. 76 FR 74831 - Aging Management of Stainless Steel Structures and Components in Treated Borated Water

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-01

    ...aging management of stainless steel structures and components exposed...aging management of stainless steel structures and components exposed...guidance inappropriately credits boron as a corrosion inhibitor in...material and cracking of stainless steel structures and components...

  3. 76 FR 43981 - Circular Welded Austenitic Stainless Pressure Pipe From the People's Republic of China: Final...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-22

    ...Austenitic Stainless Pressure Pipe from the People's Republic...austenitic stainless pressure pipe not greater than 14 inches in...specifications; (2) boiler, heat exchanger, superheater, refining...Jiuli Welded Stainless Steel Pipe Co., Ltd.'', dated...

  4. PH urine test (image)

    MedlinePLUS

    The urine is tested for acidity or alkalinity (pH) because certain medications are more effective in acidic or alkaline environments. Medications for urinary tract infections are more effective when the urine ...

  5. Electrode and pH effects on electrochemical reactions during ohmic heating

    Microsoft Academic Search

    Chaminda P. Samaranayake; Sudhir K. Sastry

    2005-01-01

    Undesirable electrochemical phenomena at electrode|solution interfaces during ohmic heating can be avoided or effectively inhibited by choosing an appropriate electrode material. We attempted to understand the electrochemical behavior of four types of electrode materials: titanium, stainless steel, platinized-titanium, and graphite at pH 3.5, 5.0, and 6.5. The electrodes were examined comparatively using a 60 Hz sinusoidal alternating current. Analyses of

  6. Surface modification of superaustenitic and maraging stainless steels by low-temperature gas-phase carburization

    NASA Astrophysics Data System (ADS)

    Gentil, Johannes

    Low-temperature gas-phase carburization of 316L austenitic stainless steel was developed in recent years by the Swagelok company. This process generates great mechanical and electrochemical surface properties. Hardness, wear resistance, fatigue behavior, and corrosion resistance are dramatically improved, while the formation of carbides is effectively suppressed. This new technique is of technical, economical, but especially of scientific interest because the surface properties of common stainless steel can be enhanced to a level of more sophisticated and more expensive superalloys. The consequential continuation of previous research is the application of the carburization process to other steel grades. Differences in chemical composition, microstructure, and passivity between the various alloys may cause technical problems and it is expected that the initial process needs to be optimized for every specific material. This study presents results of low-temperature carburization of AL-6XN (superaustenitic stainless steel) and PH13-8Mo (precipitation-hardened martensitic stainless steel). Both alloys have been treated successfully in terms of creating a hardened surface by introducing high amounts of interstitially dissolved carbon. The surface hardness of AL-6XN was increased to 12GPa and is correlated with a colossal carbon supersaturation at the surface of up to 20 at.%. The hardened case develops a carburization time-dependent thickness between 10mum after one carburization cycle and up to 35mum after four treatments and remains highly ductile. Substantial broadening of X-ray diffraction peaks in low-temperature carburized superaustenitic stainless steels are attributed to the generation of very large compressive biaxial residual stresses. Those large stresses presumably cause relaxations of the surface, so-called undulations. Heavily expanded regions of carburized AL-6XN turn ferromagnetic. Non-carburized AL-6XN is known for its outstanding corrosion resistance, which is not impaired upon carburization. The passive film as analyzed by XPS is fully intact. Carbon concentration levels in PH13-8Mo reach 10 at.% and correlate with a surface hardness of up to 14GPa. Indication for the transformation from martensite to austenite during the process are observed. In this context, the shape of the carbon concentration-depth profile can be explained. Also the absence of carbides, as analyzed by TEM, can be rationalized. Upon cooling to room temperature, most of the austenite backtransforms into martensite and the surface regains its ferromagnetic properties. Compressive biaxial residual stresses in carburized PH13-8Mo are measured around (2--2.5)GPa. The applied low-temperature carburization process gives rise to a substantial loss in corrosion resistance of PH13-8Mo. Possible reasons including the observed formation of internal and external oxides as well as the change in alloy composition are discussed. Due to the penetration depth of X-rays into the probed specimen surface, a carbon concentration gradient may cause detectable asymmetry of diffraction peaks for certain alloys and under certain conditions. For the first time, this effect is rationalized, explained, and demonstrated on the basis of measured data.

  7. Ph.D. Manual PH.D. PROGRAM

    E-print Network

    Gilchrist, James F.

    Ph.D. Manual 1 PH.D. PROGRAM IN SCHOOL PSYCHOLOGY Manual of Policies and Procedures College://www.lehigh.edu/education/sp/phd_sp.html Approved: May 1985 Last Revision: July 2010 #12;Ph.D. Manual 2 Table of Contents Program Philosophy..................................................................................... 3 Differentiation of Ph.D. & Ed.S. Programs................................................... 8

  8. Adhesion measurements and chemical and microstructural characterization at interfaces of titanium nitride and titanium aluminum nitride coatings on stainless steel, inconel and titanium alloys

    Microsoft Academic Search

    Robert Dallas James

    1997-01-01

    To assess the adhesion of nitride coatings on metal alloys, Ti 6Al-4V, 17-4 PH stainless steel and Inconel 718 alloy substrates were coated with titanium nitride (TiN) using both cathodic arc and electron beam evaporation. Titanium aluminum nitride ((Ti,Al)N) was also deposited using cathodic arc evaporation. X-ray photoelectron, Auger electron, and energy dispersive x-ray spectroscopies were used in tandem with

  9. Investigations of thiosulfate accumulation on 304 stainless steel in neutral solutions by radioactive labeling, electrochemistry, Auger electron and X-ray photoelectron spectroscopy methods

    Microsoft Academic Search

    A. E. Thomas; A. Kolics; A. Wieckowski

    1997-01-01

    Thiosulfate accumulation on 304 stainless steel in near neutral solutions (pH â¼5.6) was studied using in situ techniques: electrochemistry and radiochemistry, as well as by Auger electron spectroscopy depth profiling and angle-resolved x-ray photoelectron spectroscopy in ultrahigh vacuum. It was found that thiosulfate accumulation is an irreversible process and occurs over a broad electrode potential range. Thiosulfate surface concentration is

  10. Inactivation of Escherichia coli, Listeria monocytogenes, Pseudomonas aeruginosa and Staphylococcus aureus on stainless steel and glass surfaces by neutral electrolysed water

    Microsoft Academic Search

    M. A. Deza; M. Araujo; M. J. Garrido

    2005-01-01

    M.A. DEZA, M. ARAUJO AND M. J. GARRIDO. 2005. Aim: To ascertain the efficacy of neutral electrolysed water (NEW) in reducing Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Listeria monocytogenes on glass and stainless steel surfaces. Its effectiveness for that purpose is compared with that of a sodium hypochlorite (NaClO) solution with similar pH, oxidation-reduction potential (ORP) and active chlorine

  11. COMPARISON OF THE CORROSION OF CARBON STEEL, STAINLESS STEE, INCONEL-X, MONEL AND STELLITE IN THE KER MOCK-UP TUBES WITH OUT-OF-REACTOR LOOPS

    Microsoft Academic Search

    Larrick

    1960-01-01

    Water corrosion tests were run on carbon steel (A-212), stainless steel ; (304), Monel, Inconel-X, and Stellite-12 in KER-1 and KER-2 in-reactor ; recirculating loops with the NPR as the reactor. The water was adjusted to pH 10 ; and 4.3 with LiOH and HâPOâ, respectively. The data were compared ; with those obtained in small out-of-reactor corrosion test loops

  12. Gas Atomization of Stainless Steel - Slow Motion

    SciTech Connect

    None

    2011-01-01

    Stainless steel liquid atomized by supersonic argon gas into a spray of droplets at ~1800ºC. Atomization of metal requires high pressure gas and specialized chambers for cooling and collecting the powders without contamination. The critical step for morphological control is the impingement of the gas on the melt stream. The video is a black and white high speed video of a liquid metal stream being atomized by high pressure gas. This material was atomized at the Ames Laboratory's Materials Preparation Center http://www.mpc.ameslab.gov

  13. Durable icephobic coating for stainless steel.

    PubMed

    Boinovich, Ludmila B; Emelyanenko, Alexandre M; Ivanov, Vladimir K; Pashinin, Andrei S

    2013-04-10

    In this work, we present a modification of a stainless steel surface to impart superhydrophobic properties to it that are robust with respect to mechanical stresses associated with cyclic icing/deicing treatment, as well as to long-term contact with aqueous media and high humidity. The durability of the superhydrophobic state is ensured by the texture with multimodal roughness stable against mechanical stresses and a 2D polymer network of fluorooxysilane chemically bound to the texture elements. The designed superhydrophobic coating is characterized by contact angles exceeding 155° and a maximum rolling angle of 42° after 100 icing/deicing cycles. PMID:23470194

  14. Formability Limits of a SPIFed Stainless Steel

    NASA Astrophysics Data System (ADS)

    Radu, Crina; Thibaud, Sebastian

    2011-05-01

    Single point incremental forming (SPIF) is a new cheep, flexible solution for manufacturing rapid prototypes and products with shorts series. Besides, it has been experimentally proven by different researchers that SPIF assures a higher formability than conventional sheet forming processes, enlarging thus its applicability. The aim of this paper is to examine the forming limits of a stainless steel when it is processed by SPIF. Since sheet thickness has an important role in this process, the analysis is performed for three different thicknesses of metal sheet: 0.8, 1 and 1.2 mm respectively.

  15. Nanostructured nickel-free austenitic stainless steel/hydroxyapatite composites.

    PubMed

    Tulinski, Maciej; Jurczyk, Mieczyslaw

    2012-11-01

    In this work Ni-free austenitic stainless steels with nanostructure and their nanocomposites with hydroxyapatite are presented and characterized by means of X-ray diffraction and optical profiling. The samples were synthesized by mechanical alloying, heat treatment and nitriding of elemental microcrystalline powders with addition of hydroxyapatite (HA). In our work we wanted to introduce into stainless steel hydroxyapatite ceramics that have been intensively studied for bone repair and replacement applications. Such applications were chosen because of their high biocompatibility and ability to bond to bone. Since nickel-free austenitic stainless steels seem to have better mechanical properties, corrosion resistance and biocompatibility compared to 316L stainless steels, it is possible that composite made of this steel and HA could improve properties, as well. Mechanical alloying and nitriding are very effective technologies to improve the corrosion resistance of stainless steel. Similar process in case of nanocomposites of stainless steel with hydroxyapatite helps achieve even better mechanical properties and corrosion resistance. Hence nanocrystalline nickel-free stainless steels and nickel-free stainless steel/hydroxyapatite nanocomposites could be promising bionanomaterials for use as a hard tissue replacement implants, e.g., orthopedic implants. In such application, the surface roughness and more specifically the surface topography influences the proliferation of cells (e.g., osteoblasts). PMID:23421285

  16. Hydrogen embrittlement of stainless steel overlay materials for hydrogenators

    Microsoft Academic Search

    D. Hardie; J. Xu; E. A. Charles; Y. Wei

    2004-01-01

    An investigation was carried out of the effect of hydrogen absorption on the tensile ductility of composite specimens representing stainless steel weld overlays on low alloy steel substrates as used in the fabrication of hydrogenators. Specimens of the two stainless steels (AISI 309 and 347) involved in hydrogen cracking were also fractured in tension at strain rates between 5.9×10?6 and

  17. Scrap stainless steel detection using a pulsed electromagnetic field

    Microsoft Academic Search

    M. B. Mesina; T. P. R. de Jong; W. L. Dalmijn

    2005-01-01

    A pulsed electromagnetic sensor (PEMS) utilising the difference in electrical and magnetic properties of metals was designed for automatic sorting of scrap stainless steel (SS). Experimental results for the identification and separation of stainless steel are presented. The design of a prototype being developed at Delft University of Technology and the results obtained in the laboratory are also discussed.

  18. New Method For Joining Stainless Steel to Titanium

    NASA Technical Reports Server (NTRS)

    Emanuel, W. H.

    1982-01-01

    In new process, edge of stainless-steel sheet is perforated, and joined to titanium by resistance seam welding. Titanium flows into perforations, forming a strong interlocking joint. Process creates a quasi-metallurgical bond between the thin sheets of stainless steel and titanium.

  19. VIEW OF PRECISION EQUIPMENT USED IN STAINLESS COMPONENT MANUFACTURING. THE ...

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

    VIEW OF PRECISION EQUIPMENT USED IN STAINLESS COMPONENT MANUFACTURING. THE FACILITY WAS DESCRIBED AS THE MOST MODERN NON-NUCLEAR MANUFACTURING BUILDING IN THE U.S. DEPARTMENT OF ENERGY COMPLEX, WITH MANY PRECISION INSTRUMENTS. (9/21/83) - Rocky Flats Plant, Stainless Steel & Non-Nuclear Components Manufacturing, Southeast corner of intersection of Cottonwood & Third Avenues, Golden, Jefferson County, CO

  20. Variant selection in samples of austenitic stainless steel cold

    E-print Network

    Cambridge, University of

    Variant selection in samples of austenitic stainless steel cold rolled and deformed by tension texture of samples deformed by cold rolling. ­ Comparing texture measured by EBSD in cold rolled samples Tensor for deformation in a tension test Tensor for deformation by cold rolling #12;Austenitic stainless

  1. Residual stress analysis of structural stainless steel sections

    Microsoft Academic Search

    R. B. Cruise; L. Gardner

    2008-01-01

    The magnitude and distribution of residual stresses in structural carbon steel sections have been thoroughly investigated. However, few residual stress measurements have been made on structural stainless steel sections. Stainless steel has differing material stress–strain characteristics and thermal properties to carbon steel, both of which influence the formation of residual stresses. This suggests that established carbon steel residual stress models

  2. Thermal conductivity of Inconel 718 and 304 stainless steel

    Microsoft Academic Search

    J. N. Sweet; E. P. Roth; M. Moss

    1987-01-01

    The results of thermal conductivity measurements on Inconel 718 and 304 stainless steel by the comparative and flash diffusivity techniques are reported for the temperature range 0–700°C. For 304 stainless steel, excellent agreement with published data is found for the specific heat, thermal diffusivity, and thermal conductivity. In the case of Inconel 718, the measurements show that the conductivity depends

  3. Small-scale resistance spot welding of austenitic stainless steels

    Microsoft Academic Search

    Shinji Fukumoto; Kana Fujiwara; Shin Toji; Atsushi Yamamoto

    2008-01-01

    Small-scale resistance spot welding (SSRSW) was carried out for austenitic stainless steels. A weld lobe that shows the process window for making sound joints was obtained for type 304 stainless steel thin sheets, and the effects of welding current, force and weld time on joint strength and nugget size were investigated. The cooling rate that was estimated from the solidification

  4. Microstructural analysis of austenitic stainless steel laser welds

    Microsoft Academic Search

    J. M. Vitek; S. A. David

    1981-01-01

    Analysis of laser welded type 308 stainless steel has shown that the high cooling rates encountered in the process have noticeably altered the structures. Results show promise in solving the common problems of hot cracking and elevated temperature embrittlement in austenitic stainless steel welds. The solidification mode is changed from one of primary ferrite formation to primary austenite. This change

  5. Duplex Stainless Steel Welds and their Susceptibility to Intergranular Corrosion

    Microsoft Academic Search

    B. Gideon; L. Ward; G. Biddle

    Duplex stainless steels (DSS) as alternatives to conventional austenitic stainless steels for the construction of pipelines is becoming more wide-spread, particularly for sour service applications where corrosion resistance \\/ stress corrosion cracking resistance is required in aggressive chloride \\/ sulphide environments. While these steels show many superior characteristics, limitations are associated with the welding of these steels, particularly controlling the

  6. 6. DETAIL VIEW OF SPIN FORM FURNACE FOR STAINLESS STEEL ...

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

    6. DETAIL VIEW OF SPIN FORM FURNACE FOR STAINLESS STEEL FABRICATION. STAINLESS STEEL WAS MACHINED IN SIDE A OF THE BUILDING, BEGINNING IN 1957. (4/24/78) - Rocky Flats Plant, Uranium Rolling & Forming Operations, Southeast section of plant, southeast quadrant of intersection of Central Avenue & Eighth Street, Golden, Jefferson County, CO

  7. Tensile-property characterization of thermally aged cast stainless steels

    SciTech Connect

    Michaud, W.F.; Toben, P.T.; Soppet, W.K.; Chopra, O.K. [Argonne National Lab., IL (United States)

    1994-02-01

    The effect of thermal aging on tensile properties of cast stainless steels during service in light water reactors has been evaluated. Tensile data for several experimental and commercial heats of cast stainless steels are presented. Thermal aging increases the tensile strength of these steels. The high-C Mo-bearing CF-8M steels are more susceptible to thermal aging than the Mo-free CF-3 or CF-8 steels. A procedure and correlations are presented for predicting the change in tensile flow and yield stresses and engineering stress-vs.-strain curve of cast stainless steel as a function of time and temperature of service. The tensile properties of aged cast stainless steel are estimated from known material information, i.e., chemical composition and the initial tensile strength of the steel. The correlations described in this report may be used for assessing thermal embrittlement of cast stainless steel components.

  8. Tensile-property characterization of thermally aged cast stainless steels.

    SciTech Connect

    Michaud, W. F.; Toben, P. T.; Soppet, W. K.; Chopra, O. K.; Energy Technology

    1994-03-03

    The effect of thermal aging on tensile properties of cast stainless steels during service in light water reactors has been evaluated. Tensile data for several experimental and commercial heats of cast stainless steels are presented. Thermal aging increases the tensile strength of these steels. The high-C Mo-bearing CF-8M steels are more susceptible to thermal aging than the Mo-free CF-3 or CF-8 steels. A procedure and correlations are presented for predicting the change in tensile flow and yield stresses and engineering stress-vs.-strain curve of cast stainless steel as a function of time and temperature of service. The tensile properties of aged cast stainless steel are estimated from known material information, i.e., chemical composition and the initial tensile strength of the steel. The correlations described in this report may be used for assessing thermal embrittlement of cast stainless steel components.

  9. Evaluation of the stress corrosion behavior of selected stainless steels

    SciTech Connect

    Dorning, R.E. II

    1983-11-05

    The objective of this investigation was to determine the stress corrosion behavior of selected stainless steels in several fluorinating environments. The possibility of stress corrosion cracking or pitting which could substantially reduce the serviceability of the stainless steels was the primary concern. Laboratory testing indicated that stress corrosion cracking or other forms of localized attack of the austenitic stainless steels tested (304, 304-L, 316, and 316-L) would not occur in the dry gas environments investigated. AISI 316 and 316-L stainless steels exhibited no significant corrosion in any of the test environments. Stressed 304 and 304-L stainless steels exhibited increased general corrosion and pitting when moisture was added to the fluorinating environment. 3 refs., 1 fig., 3 tabs.

  10. Numerical simulation of damage in two-scale model of stainless steel 15-5PH

    Microsoft Academic Search

    Tong Wu; Philippe Gilles; Michel Coret; Alain Combescure

    2008-01-01

    This study concerns the modeling of the damage induced by a complex history of thermo-elasto-plastic multiphase in heat-affected-zone (HAZ) of welding. In this work, a twoscale model of elasto-plastic damaged multiphase is developed. The constitutive equations of the model are a coupling between the ductile damage, elasto-plastic deformations and phase transformation.

  11. Environment-Assisted Cracking in Custom 465 Stainless Steel

    NASA Astrophysics Data System (ADS)

    Lee, E. U.; Goswami, R.; Jones, M.; Vasudevan, A. K.

    2011-02-01

    The influence of cold work and aging on the environment-assisted cracking (EAC) behavior and mechanical properties of Custom 465 stainless steel (SS) was studied. Four sets of specimens were made and tested. All specimens were initially solution annealed, rapidly cooled, and refrigerated (SAR condition). The first specimen set was steel in the SAR condition. The second specimen set was aged to the H1000 condition. The third specimen set was 60 pct cold worked, and the fourth specimen set was 60 pct cold worked and aged at temperatures ranging from 755 K to 825 K (482 °C to 552 °C) for 4 hours in air. The specimens were subsequently subjected to EAC and mechanical testing. The EAC testing was conducted, using the rising step load (RSL) technique, in aqueous solutions of NaCl of pH 7.3 with concentrations ranging from 0.0035 to 3.5 pct at room temperature. The microstructure, dislocation substructure, and crack paths, resulting from the cold work, aging, or subsequent EAC testing, were examined by optical microscopy, transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The aging of the cold-worked specimens induced carbide precipitation within the martensite lath, but not at the lath or packet boundaries. In the aged specimens, as aging temperature rose, the threshold stress intensity for EAC (KIEAC), elongation, and fracture toughness increased, but the strength and hardness decreased. The KIEAC also decreased with increasing yield strength and NaCl concentration. In the SAR and H1000 specimens, the EAC propagated along the prior austenite grain boundary, while in the cold-worked and cold-worked and aged specimens, the EAC propagated along the martensite lath, and its packet and prior austenite grain boundaries. The controlling mechanism for the observed EAC was identified to be hydrogen embrittlement.

  12. Embrittlement of austenitic stainless steel welds

    SciTech Connect

    David, S.A.; Vitek, J.M. [Oak Ridge National Lab., TN (United States). Metals and Ceramics Div.

    1997-12-31

    The microstructure of type-308 austenitic stainless steel weld metal containing {gamma} and {delta} and ferrite is shown. Typical composition of the weld metal is Cr-20.2, Ni-9.4, Mn-1.7, Si-0.5, C-0.05, N-0.06 and balance Fe (in wt %). Exposure of austenitic stainless steel welds to elevated temperatures can lead to extensive changes in the microstructural features of the weld metal. On exposure to elevated temperatures over a long period of time, a continuous network of M{sub 23}C{sub 6} carbide forms at the austenite/ferrite interface. Upon aging at temperatures between 550--850 C, ferrite in the weld has been found to be unstable and transforms to sigma phase. These changes have been found to influence mechanical behavior of the weld metal, in particular the creep-rupture properties. For aging temperatures below 550 C the ferrite decomposes spinodally into {alpha} and {alpha}{prime} phases. In addition, precipitation of G-phase occurs within the decomposed ferrite. These transformations at temperatures below 550 C lead to embrittlement of the weld metal as revealed by the Charpy impact properties.

  13. Weldment for austenitic stainless steel and method

    DOEpatents

    Bagnall, Christopher (Hempfield, PA); McBride, Marvin A. (Hempfield, PA)

    1985-01-01

    For making defect-free welds for joining two austenitic stainless steel mers, using gas tungsten-arc welding, a thin foil-like iron member is placed between the two steel members to be joined, prior to making the weld, with the foil-like iron member having a higher melting point than the stainless steel members. When the weld is formed, there results a weld nugget comprising melted and then solidified portions of the joined members with small portions of the foil-like iron member projecting into the solidified weld nugget. The portions of the weld nugget proximate the small portions of the foil-like iron member which project into the weld nugget are relatively rich in iron. This causes these iron-rich nugget portions to display substantial delta ferrite during solidification of the weld nugget which eliminates weld defects which could otherwise occur. This is especially useful for joining austenitic steel members which, when just below the solidus temperature, include at most only a very minor proportion of delta ferrite.

  14. Cast alumina forming austenitic stainless steels

    DOEpatents

    Muralidharan, Govindarajan; Yamamoto, Yukinori; Brady, Michael P

    2013-04-30

    An austenitic stainless steel alloy consisting essentially of, in terms of weight percent ranges 0.15-0.5C; 8-37Ni; 10-25Cr; 2.5-5Al; greater than 0.6, up to 2.5 total of at least one element selected from the group consisting of Nb and Ta; up to 3Mo; up to 3Co; up to 1W; up to 3Cu; up to 15Mn; up to 2Si; up to 0.15B; up to 0.05P; up to 1 total of at least one element selected from the group consisting of Y, La, Ce, Hf, and Zr; <0.3Ti+V; <0.03N; and, balance Fe, where the weight percent Fe is greater than the weight percent Ni, and wherein the alloy forms an external continuous scale comprising alumina, and a stable essentially single phase FCC austenitic matrix microstructure, the austenitic matrix being essentially delta-ferrite free and essentially BCC-phase-free. A method of making austenitic stainless steel alloys is also disclosed.

  15. Citric Acid Passivation of Stainless Steel

    NASA Technical Reports Server (NTRS)

    Yasensky, David; Reali, John; Larson, Chris; Carl, Chad

    2009-01-01

    Passivation is a process for cleaning and providing corrosion protection for stainless steel. Currently, on Kennedy Space Center (KSC), only parts passivated with nitric acid are acceptable for use. KSC disposes of approximately 125gal of concentrated nitric acid per year, and receives many parts from vendors who must also dispose of used nitric acid. Unfortunately, nitric acid presents health and environmental hazards. As a result, several recent industry studies have examined citric acid as an alternative. Implementing a citric acid-based passivation procedure would improve the health and environmental safety aspects of passivation process. However although there is a lack of published studies that conclusively prove citric acid is a technically sound passivation agent. In 2007, NASA's KSC Materials Advisory Working Group requested the evaluation of citric acid in place of nitric acid for passivation of parts at KSC. United Space Alliance Materials & Processes engineers have developed a three-phase test plan to evaluate citric acid as an alternative to nitric acid on three stainless steels commonly used at KSC: UNS S30400, S41000, and S17400. Phases 1 and 2 will produce an optimized citric acid treatment based on results from atmospheric exposure at NASA's Beach Corrosion Facility. Phase 3 will compare the optimized solution(s) with nitric acid treatments. If the results indicate that citric acid passivates as well or better than nitric acid, NASA intends to approve this method for parts used at the Kennedy Space Center.

  16. Experimental study of fouling and cleaning of sintered stainless steel membrane in electro-microfiltration of calcium salt particles.

    PubMed

    Qin, Frank G F; Mawson, John; Zeng, Xin An

    2011-01-01

    Sintered stainless steel (SSS) microfiltration membranes, which served as electrode directly, were used for the experiment of separating Alamin, a calcium salt and protein containing particles, found in dairy processing. Fouling and cleaning of the SSS membranes under the application of an external electric field were studied. The imposed electric field was found, diverging the pH of permeate and retentate. This in turn altered the solubility of the calcium salt and impacted the performance of electro microfiltration membrane. Using electric field as an enhanced cleaning-in-place (CIP) method in back flushing SSS membrane was also studied. PMID:24957615

  17. pH optrode

    DOEpatents

    Northrup, M. Allen (Berkeley, CA); Langry, Kevin C. (Tracy, CA)

    1993-01-01

    A process is provided for forming a long-lasting, stable, pH-sensitive dye-acrylamide copolymer useful as a pH-sensitive material for use in an optrode or other device sensitive to pH. An optrode may be made by mechanically attaching the copolymer to a sensing device such as an optical fiber.

  18. Final Report, Volume 1, Metallurgical Evaluation of Cast Duplex Stainless Steels and their Weldments

    Microsoft Academic Search

    Songqing Wen; Carl Lundin; Greg Batten

    2005-01-01

    Duplex stainless steels (DSS) are being specified for chloride containing environments due to their enhanced pitting and stress corrosion cracking resistance. They exhibit improved corrosion performance over the austenitic stainless steels. Duplex stainless steels also offer improved strength properties and are available in various wrought and cast forms. Selected grades of duplex stainless steel castings and their welds, in comparison

  19. Analysis of Stainless Steel Sandwich Panels with a Metal Foam Care for Lightweight Fan Blade Design

    NASA Technical Reports Server (NTRS)

    Min, James B.; Ghosn, Louis J.; Lerch, Bradley A.; Raj, Sai V.; Holland, Frederic A., Jr.; Hebsur, Mohan G.

    2004-01-01

    The quest for cheap, low density and high performance materials in the design of aircraft and rotorcraft engine fan and propeller blades poses immense challenges to the materials and structural design engineers. Traditionally, these components have been fabricated using expensive materials such as light weight titanium alloys, polymeric composite materials and carbon-carbon composites. The present study investigates the use of P sandwich foam fan blade made up of solid face sheets and a metal foam core. The face sheets and the metal foam core material were an aerospace grade precipitation hardened 17-4 PH stainless steel with high strength and high toughness. The stiffness of the sandwich structure is increased by separating the two face sheets by a foam core. The resulting structure possesses a high stiffness while being lighter than a similar solid construction. Since the face sheets carry the applied bending loads, the sandwich architecture is a viable engineering concept. The material properties of 17-4 PH metal foam are reviewed briefly to describe the characteristics of the sandwich structure for a fan blade application. A vibration analysis for natural frequencies and P detailed stress analysis on the 17-4 PH sandwich foam blade design for different combinations of skin thickness and core volume %re presented with a comparison to a solid titanium blade.

  20. Mitigating Localized Corrosion Using Thermally Sprayed Aluminum (TSA) Coatings on Welded 25% Cr Superduplex Stainless Steel

    NASA Astrophysics Data System (ADS)

    Paul, S.; Lu, Q.; Harvey, M. D. F.

    2015-04-01

    Thermally sprayed aluminum (TSA) coating has been increasingly used for the protection of carbon steel offshore structures, topside equipment, and flowlines/pipelines exposed to both marine atmospheres and seawater immersion conditions. In this paper, the effectiveness of TSA coatings in preventing localized corrosion, such as pitting and crevice corrosion of 25% Cr superduplex stainless steel (SDSS) in subsea applications, has been investigated. Welded 25% Cr SDSS (coated and uncoated) with and without defects, and surfaces coated with epoxy paint were also examined. Pitting and crevice corrosion tests, on welded 25% Cr SDSS specimens with and without TSA/epoxy coatings, were conducted in recirculated, aerated, and synthetic seawater at 90 °C for 90 days. The tests were carried out at both the free corrosion potentials and an applied cathodic potential of -1100 mV saturated calomel electrode. The acidity (pH) of the test solution was monitored daily and adjusted to between pH 7.5 and 8.1, using dilute HCl solution or dilute NaOH, depending on the pH of the solution measured during the test. The test results demonstrated that TSA prevented pitting and crevice corrosion of 25% Cr SDSS in artificial seawater at 90 °C, even when 10-mm-diameter coating defect exposing the underlying steel was present.

  1. Effect of condenser design on stress corrosion cracking of stainless alloys in boiling chloride solutions

    SciTech Connect

    Chiang, Y.L.; Streicher, M.A. [Univ. of Delaware, Newark, DE (United States)

    1998-09-01

    The design of condensers used to reflux boiling chloride solutions for stress corrosion tests on stainless alloys was shown to have a significant effect on time to cracking. This effect resulted from the different steady-state concentrations of oxygen produced by various types of condensers. The condenser that provided the least amount of preheating before returning the condensate to the solution established the largest concentrations of air (oxygen) in the boiling solution and the shortest times to failure by stress corrosion cracking (SCC). This was demonstrated with magnesium chloride (MgCl{sub 2}) and sodium chloride (NaCl) solutions on type 304 stainless steel (UNS S30400), Carpenter 20 Cb-3 (UNS N08020), and Incoloy 825 (UNS N08825). In MgCl{sub 2}, the effect of oxygen on stress corrosion depended upon the concentration of the solution. The effect was maximum in the range from 24% to 32% and decreased or disappeared at higher concentrations depending upon the alloy. These findings can be used to assess previously published data, for the design of new experiments, and for the development of new evaluation tests. Using a solution of 26% NaCl with phosphoric acid (H{sub 3}PO{sub 4}) to reduce the pH to 1.0 provides a more realistic method for evaluating alloys for service on plants than testing in MgCl{sub 2} solutions.

  2. Cryogenic coefficient of thermal expansion measurements of type 440 and 630 stainless steel

    NASA Astrophysics Data System (ADS)

    Cease, H.; Alvarez, M.; Flaugher, B.; Montes, J.

    2014-01-01

    The Dark Energy Camera is now installed on the Blanco 4m telescope at the Cerro Tololo Inter-American Observatory in Chile. The camera is cooled to 170K using a closed loop two-phase liquid nitrogen system. A submerged centrifugal pump is used to circulate the liquid from the base of the telescope to the camera in the prime focus cage. As part of the pump maintenance schedule, the rotor shaft bearings are periodically replaced. Common bearing and shaft materials are type 440 and 630 (17-4 PH) stainless steel. The coefficient of thermal expansion of the materials used is needed to predict the shaft and bearing housing dimensional changes at the 77K pump operating temperature. The thermal expansion from room temperature to 77K of type 440 and 630 stainless steel is presented . Measurements are performed using the ASTM E228 standard with a quartz push-rod dilatometer test stand. Aluminum 6061-T6 is used to calibrate the test stand.

  3. Kinetics of Pseudomonas aeruginosa adhesion to 304 and 316-L stainless steel: role of cell surface hydrophobicity.

    PubMed Central

    Vanhaecke, E; Remon, J P; Moors, M; Raes, F; De Rudder, D; Van Peteghem, A

    1990-01-01

    Fifteen different isolates of Pseudomonas aeruginosa were used to study the kinetics of adhesion to 304 and 316-L stainless steel. Stainless steel plates were incubated with approximately 1.5 X 10(7) CFU/ml in 0.01 M phosphate-buffered saline (pH 7.4). After the plates were rinsed with the buffer, the number of adhering bacteria was determined by a bioluminescence assay. Measurable adhesion, even to the electropolished surfaces, occurred within 30 s. Bacterial cell surface hydrophobicity, as determined by the bacterial adherence to hydrocarbons test and the contact angle measurement test, was the major parameter influencing the adhesion rate constant for the first 30 min of adhesion. A parabolic relationship between the CAM values and the logarithm of the adhesion rate constants (In k) was established. No correlation between either the salt aggregation or the improved salt aggregation values and the bacterial adhesion rate constants could be found. Since there was no significant correlation between the bacterial electrophoretic mobilities and the In k values, the bacterial cell surface charge seemed of minor importance in the process of adhesion of P. aeruginosa to 304 and 316-L stainless steel. PMID:2107796

  4. A preliminary ferritic-martensitic stainless steel constitution diagram

    SciTech Connect

    Balmforth, M.C.; Lippold, J.C. [Ohio State Univ., Columbus, OH (United States). Welding and Joining Metallurgy Group

    1998-01-01

    This paper describes preliminary research to develop a constitution diagram that will more accurately predict the microstructure of ferritic and martensitic stainless steel weld deposits. A button melting technique was used to produce a wide range of compositions using mixtures of conventional ferritic and martensitic stainless steels, including types 403, 409, 410, 430, 439 and 444. These samples were prepared metallographically, and the vol-% ferrite and martensite was determined quantitatively. In addition, the hardness and ferrite number (FN) were measured. Using this data, a preliminary constitution diagram is proposed that provides a more accurate method for predicting the microstructures of arc welds in ferritic and martensitic stainless steels.

  5. [Study on biocompatibility of MIM 316L stainless steel].

    PubMed

    Wang, Guohui; Zhu, Shaihong; Li, Yiming; Zhao, Yanzhong; Zhou, Kechao; Huang, Boyun

    2007-04-01

    This study was aimed to evaluate the biocompatibility of metal powder injection molding (MIM) 316L stainless steel. The percentage of S-period cells was detected by flow cytometry after L929 cells being incubated with extraction of MIM 316L stainless steel, and titanium implant materials for clinical application were used as control. In addition, both materials were implanted in animals and the histopathological evaluations were carried out. The statistical analyses show that there are no significant differences between the two groups (P > 0.05), which demonstrate that MIM 316L stainless steel has good biocompatibility. PMID:17591253

  6. Corrosion resistance of stainless steel in chloride contaminated concrete

    SciTech Connect

    Gu, P.; Elliott, S.; Beaudoin, J.J. [National Research Council, Ottawa, Ontario (Canada); Arsenault, B. [National Research Council, Boucherville, Quebec (Canada)

    1996-08-01

    The results of an investigation of the performance of 2-year-old stainless steel reinforced concrete specimens which were previously placed in an aggressive aqueous solution containing chlorides are presented. This study consisted of corrosion rate testing of reinforced concrete samples with normal reinforcing steel and stainless steel rebars by means of the a.c. impedance spectroscopy. The equivalent circuit simulation analysis method was applied in the data interpretation. The performance and effectiveness of stainless steel in preventing corrosion in chloride contaminated concrete was evaluated.

  7. Stress-corrosion cracking of sensitized type 304 stainless steel in thiosulfate solutions

    NASA Astrophysics Data System (ADS)

    Newman, R. C.; Sieradzki, K.; Isaacs, H. S.

    1982-11-01

    The stress corrosion cracking of a sensitized Type 304 stainless steel has been studied at room temperature using controlled potentials and two concentrations of sodium thiosulfate. In both constant extension rate and constant load tests, the crack velocities attain extremely high values, up to 8 ?m s-1. Scratching electrode experiments conducted at various pH values on simulated grain boundary material show that both the crack initiation frequency and crack velocity are closely related to the repassivation rate of the grain boundary material as expected on a dissolution-controlled mechanism; however, the maximum crack velocity at any potential is consistently about two orders of magnitude higher than that predicted from the electrochemical data. Frequent grain boundary separation ahead of the crack tip is thought to occur, but retarded repassivation of the grain boundary material is a necessary feature of the cracking. Effects of strain-generated martensite are discussed.

  8. Stress-corrosion cracking of sensitized type 304 stainless steel in thiosulfate solutions

    SciTech Connect

    Newman, R.C.; Isaacs, H.S.; Sieradzki, K.

    1982-11-01

    The stress corrosion cracking of a sensitized Type 304 stainless steel has been studied at room temperature using controlled potentials and two concentrations of sodium thiosulfate. In both constant extension rate and constant load tests, the crack velocities attain extremely high values, up to 8 ..mu..m s/sup -1/. Scratching electrode experiments conducted at various pH values on simulated grain boundary materials show that both the crack initiation frequency and crack velocity are closely related to the repassivation rate of the grain boundary material as expected on a dissolution-controlled mechanism; however, th maximum crack velocity at any potential is consistently about two orders of magnitude higher than that predicted from the electrochemical data. Frequent grain boundary separation ahead of the crack tip is thought to occur, but retarded repassivation of the grain boundary material is a necessary feature of the cracking. Effects of strain-generated martensite are discussed.

  9. Stress-corrosion cracking of sensitized type 304 stainless steel in thiosulfate solutions

    SciTech Connect

    Newman, R.C.; Sieradzki, K.; Isaacs, H.S.

    1982-11-01

    The stress corrosion cracking of a sensitized Type 304 stainless steel has been studied at room temperature using controlled potentials and two concentrations of sodium thiosulfate. In both constant extension rate and constant load tests, the crack velocities attain extremely high values, up to 8 ..mu..m s/sup -1/. Scratching electrode experiments conducted at various pH values on simulated grain boundary material show that both the crack initiation frequency and crack velocity are closely related to the repassivation rate of the grain boundary material as expected on a dissolution-controlled mechanism; however, the maximum crack velocity at any potential is consistently about two orders of magnitude higher than that predicted from the electrochemical data. Frequent grain boundary separation ahead of the crack tip is thought to occur, but retarded repassivation of the grain boundary material is a necessary feature of the cracking. Effects of strain-generated martensite are discussed.

  10. Automatic Welding of Stainless Steel Tubing

    NASA Technical Reports Server (NTRS)

    Clautice, W. E.

    1978-01-01

    To determine if the use of automatic welding would allow reduction of the radiographic inspection requirement, and thereby reduce fabrication costs, a series of welding tests were performed. In these tests an automatic welder was used on stainless steel tubing of 1/2, 3/4, and 1/2 inch diameter size. The optimum parameters were investigated to determine how much variation from optimum in machine settings could be tolerate and still result in a good quality weld. The process variables studied were the welding amperes, the revolutions per minute as a function of the circumferential weld travel speed, and the shielding gas flow. The investigation showed that the close control of process variables in conjunction with a thorough visual inspection of welds can be relied upon as an acceptable quality assurance procedure, thus permitting the radiographic inspection to be reduced by a large percentage when using the automatic process.

  11. Radiation resistant austenitic stainless steel alloys

    DOEpatents

    Maziasz, P.J.; Braski, D.N.; Rowcliffe, A.F.

    1987-02-11

    An austenitic stainless steel alloy, with improved resistance to radiation-induced swelling and helium embrittlement, and improved resistance to thermal creep at high temperatures, consisting essentially of, by weight percent: from 16 to 18% nickel; from 13 to 17% chromium; from 2 to 3% molybdenum; from 1.5 to 2.5% manganese; from 0.01 to 0.5% silicon; from 0.2 to 0.4% titanium; from 0.1 to 0.2% niobium; from 0.1 to 0.6% vanadium; from 0.06 to 0.12% carbon; from 0.01 to 0.03% nitrogen; from 0.03 to 0.08% phosphorus; from 0.005 to 0.01% boron; and the balance iron, and wherein the alloy may be thermomechanically treated to enhance physical and mechanical properties. 4 figs.

  12. Stainless steel anodes for alkaline water electrolysis and methods of making

    DOEpatents

    Soloveichik, Grigorii Lev

    2014-01-21

    The corrosion resistance of stainless steel anodes for use in alkaline water electrolysis was increased by immersion of the stainless steel anode into a caustic solution prior to electrolysis. Also disclosed herein are electrolyzers employing the so-treated stainless steel anodes. The pre-treatment process provides a stainless steel anode that has a higher corrosion resistance than an untreated stainless steel anode of the same composition.

  13. Fireside carburization of stainless steel furnace tubes

    SciTech Connect

    Mirabal, E.; Molina, C. [PDVSA-Refineria Isla, Curayao (Netherlands); Mayorga, A.; Hau, J.L. [PDVSA-Intevep, Caracas (Venezuela)

    1999-11-01

    Most heavy Venezuelan crudes are recognized for having a high total acid number (TAN) that is usually associated with a high tendency to produce naphthenic acid corrosion. To resist this type of corrosion in vacuum heaters, 9Cr-1Mo steel and stainless steels containing molybdenum are usually recommended. In 1993 the original 5Cr-1/2Mo roof tubes of the furnace in a vacuum unit were replaced by stainless steel 316Ti to minimize tube replacement and increase heater reliability. Unexpectedly, some of the new tubes failed after only three years of service, and just one year after undergoing the last turnaround inspection. The damage occurred in the form of deep holes and perforations, starting from the outside tube surface on the fireside. Coke build-up occurred due to severe operating conditions, overheating the tubes on the fireside, above 675 C (1250 F). Metallographic and Scanning Electron Microscopic (SEM) examination revealed internal and external carburization of the material due to the presence of coke and combustion ashes, respectively. The increase in the skin metal temperature facilitated the diffusion of carbon from these carbon-rich deposits into the low carbon content material (0.023 O/O).Depletion of chromium at the grain boundaries due to the massive formation of chromium carbides, resulted in a severe intergranular corrosion attack by molten salts rich in vanadium and sulfur due to asphalt burning. Normal operating practice demands the use of steam for the heater tubes to control coke build-up. This practice had been first reduced and then eliminated, during the past two years prior to the failure, because of economic incentives. This paper describes the root cause analysis conducted to account for these premature tube failures.

  14. Esophageal pH monitoring

    MedlinePLUS

    pH monitoring - esophageal; Esophageal acidity test ... to stay in the hospital for the esophageal pH monitoring. ... Esophageal pH monitoring is used to check how much stomach acid is entering the esophagus. It also checks how ...

  15. The pH scale

    NSDL National Science Digital Library

    Olivia Worland (Purdue University; Biological Sciences)

    2008-05-26

    Some animals tolerate broad changes in pH well while others do not. Human activities can create acid rain. Acid rain can change the pH of the environment and destroy entire ecosystems and habitats. For an ecosystem to function properly, its pH must be able to accommodate all of the organisms living in it.

  16. Surface modified stainless steels for PEM fuel cell bipolar plates

    DOEpatents

    Brady, Michael P [Oak Ridge, TN; Wang, Heli [Littleton, CO; Turner, John A [Littleton, CO

    2007-07-24

    A nitridation treated stainless steel article (such as a bipolar plate for a proton exchange membrane fuel cell) having lower interfacial contact electrical resistance and better corrosion resistance than an untreated stainless steel article is disclosed. The treated stainless steel article has a surface layer including nitrogen-modified chromium-base oxide and precipitates of chromium nitride formed during nitridation wherein oxygen is present in the surface layer at a greater concentration than nitrogen. The surface layer may further include precipitates of titanium nitride and/or aluminum oxide. The surface layer in the treated article is chemically heterogeneous surface rather than a uniform or semi-uniform surface layer exclusively rich in chromium, titanium or aluminum. The precipitates of titanium nitride and/or aluminum oxide are formed by the nitriding treatment wherein titanium and/or aluminum in the stainless steel are segregated to the surface layer in forms that exhibit a low contact resistance and good corrosion resistance.

  17. Radiation effects on the mechanical properties of stainless steels

    NASA Astrophysics Data System (ADS)

    Aono, Y.; Abe, H.; Kuramoto, E.; Tsukuda, N.; Takenaka, M.; Kinoshita, T.; Yoshida, H.

    1985-08-01

    Stainless steels irradiated by electrons at 77 K were deformed at 77 and 290 K in order to investigate the isochronal annealing effects on their yield strengths in the temperature range 77 to 900 K. The austenitic stainless steel (JPCA-2) showed large irradiation hardening both for the 77 and 290 K. test. Furthermore, it was found from the test at 290 K that this hardening remained up to 900 K. On the contrary, for the ferritic/martensitic or martensitic stainless steel (JFMS or HT-9) irradiation softening was observed. In particular, both the isochronal annealing curves for the HT-9 with a single tempered martensite phase indicated that a large reduction of the yield stress amounted to 20-30% and this softening did not change during annealing up to 900 K. Furthermore, the characteristic feature of the ferritic/martensitic stainless steels was examined using pure Fe-Cr and Fe-Cr-C alloys as controls.

  18. Stainless Steel in Waste Packages for TSPA-SR

    SciTech Connect

    C.D. Leigh

    2000-06-12

    The objective of the calculation is to determine how commercial spent nuclear fuel (CSNF) stainless-steel clad assemblies are distributed over the CSNF waste packages (WPs) in the Yucca Mountain repository. The calculation defines the number of CSNF WPs that will contain stainless-steel clad assemblies, and the stainless steel content, on average, in those WPs for the Total System Performance Assessment in Support of Site Recommendation (TSPA-SR). Cladding models for TSPA-SR for stainless-steel clad assemblies differ from the models used for zirconium-clad assemblies. The information derived in this calculation helps to determine how the-cladding models are applied to WPs in TSPA-SR. The calculation addresses the WP configurations for CSNF defined in an interoffice correspondence from E.P. Stroupe to D.R. Wilkins (Stroupe 2000) and shown in Table 1.

  19. 21 CFR 872.3350 - Gold or stainless steel cusp.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...3350 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3350 Gold or stainless steel cusp. (a)...

  20. Steam oxidation of boron carbide-stainless steel liquid mixtures

    NASA Astrophysics Data System (ADS)

    Dominguez, C.

    2012-08-01

    In the framework of nuclear reactor core meltdown accidents studies, the oxidation kinetics of boron carbide-stainless steel liquid mixtures exposed to argon/steam atmospheres was investigated at temperatures up to 1527 °C. A B-Cr-Si-O liquid protective layer forms on the surface of the mixtures in contact with steam. This protective layer gradually transforms into a Cr2O3-rich slag. Important quantities of liquid can be projected from the melt during oxidation. These projections are favoured by high B4C contents in the melt, high steam partial pressures and low temperatures. In addition to stainless steel-boron carbide melts, simpler compositions (pure 304L stainless steel, iron-boron, iron-boron carbide and stainless steel-boron) were studied, in order to identify the basic oxidation mechanisms.

  1. Eddy sensors for small diameter stainless steel tubes.

    SciTech Connect

    Skinner, Jack L.; Morales, Alfredo Martin; Grant, J. Brian; Korellis, Henry James; LaFord, Marianne Elizabeth; Van Blarigan, Benjamin; Andersen, Lisa E.

    2011-08-01

    The goal of this project was to develop non-destructive, minimally disruptive eddy sensors to inspect small diameter stainless steel metal tubes. Modifications to Sandia's Emphasis/EIGER code allowed for the modeling of eddy current bobbin sensors near or around 1/8-inch outer diameter stainless steel tubing. Modeling results indicated that an eddy sensor based on a single axial coil could effectively detect changes in the inner diameter of a stainless steel tubing. Based on the modeling results, sensor coils capable of detecting small changes in the inner diameter of a stainless steel tube were designed, built and tested. The observed sensor response agreed with the results of the modeling and with eddy sensor theory. A separate limited distribution SAND report is being issued demonstrating the application of this sensor.

  2. Assessment of thermal embrittlement of cast stainless steels

    SciTech Connect

    Chopra, O.K.; Shack, W.J. [Argonne National Lab., IL (United States)

    1994-05-01

    A procedure and correlations are presented for assessing thermal embrittlement and predicting Charpy-impact energy and fracture toughness J-R curve of cast stainless steel components under Light Water Reactor operating conditions from known material information. The ``saturation`` impact strength and fracture toughness of a specific cast stainless steel, i.e., the minimum value that would be achieved for the material after long-term service, is estimated from the chemical composition of the steel. Fracture properties as a function of time and temperature of reactor service are estimated from the kinetics of embrittlement, which are also determined from chemical composition. A common ``predicted lower-bound`` J-R curve for cast stainless steels of unknown chemical composition is also defined for a given grade of steel, ferrite content, and temperature. Examples of estimating fracture toughness of cast stainless steel components during reactor service are presented.

  3. Ultrasonics permits brazing complex stainless steel assembly without flux

    NASA Technical Reports Server (NTRS)

    Baker, W. H.

    1967-01-01

    Ultrasonic vibration of an assembly of stainless steel instrumentation tubes ensures brazing without flux. Vibration with an ultrasonic transducer permits the brazing material to flow down each tube in contact with a seal plug installed in a pressure vessel wall.

  4. Systems design of high performance stainless steels II. Prototype characterization

    NASA Astrophysics Data System (ADS)

    Campbell, C. E.; Olson, G. B.

    2000-10-01

    Within the framework of a systems approach, the design of a high performance stainless steel integrated processing/structure/property/performance relations with mechanistic computational models. Using multicomponent thermodynamic and diffusion software platforms, the models were integrated to design a carburizable, secondary-hardening, martensitic stainless steel for advanced gear and bearing applications. Prototype evaluation confirmed the predicted martensitic transformation temperature and the desired carburizing and tempering responses, achieving a case hardness of R c 64 in the secondary-hardened condition without case primary carbides. Comparison with a commercial carburizing stainless steel demonstrated the advantage of avoiding primary carbides to resist quench cracking associated with a martensitic start temperature gradient reversal. Based on anodic polarization measurements and salt-spray testing, the prototype composition exhibited superior corrosion resistance in comparison to the 440C stainless bearing steel, which has a significantly higher alloy Cr concentration.

  5. 3. INTERIOR VIEW OF SMOKEHOUSE UNIT; NOTE STAINLESS STEEL NOZZLES ...

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

    3. INTERIOR VIEW OF SMOKEHOUSE UNIT; NOTE STAINLESS STEEL NOZZLES THAT INTRODUCED SMOKE INTO UNIT; FLOOR IS UNPAINTED STEEL - Rath Packing Company, Smokehouse-Hog Chilling Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

  6. Fatigue behavior of welded austenitic stainless steel in different environments

    NASA Astrophysics Data System (ADS)

    Yawas, D. S.; Aku, S. Y.; Aluko, S. O.

    The fatigue behavior of welded austenitic stainless steel in 0.5 M hydrochloric acid and wet steam corrosive media has been investigated. The immersion time in the corrosive media was 30 days to simulate the effect on stainless steel structures/equipment in offshore and food processing applications and thereafter annealing heat treatment was carried out on the samples. The findings from the fatigue tests show that seawater specimens have a lower fatigue stress of 0.5 × 10-5 N/mm2 for the heat treated sample and 0.1 × 10-5 N/mm2 for the unheat-treated sample compared to the corresponding hydrochloric acid and steam samples. The post-welding heat treatment was found to increase the mechanical properties of the austenitic stainless steel especially tensile strength but it reduces the transformation and thermal stresses of the samples. These findings were further corroborated by the microstructural examination of the stainless steel specimen.

  7. 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.

  8. Fabrication of stainless steel clad tubing. [gas pressure bonding

    NASA Technical Reports Server (NTRS)

    Kovach, C. W.

    1978-01-01

    The feasibility of producing stainless steel clad carbon steel tubing by a gas pressure bonding process was evaluated. Such a tube product could provide substantial chromium savings over monolithic stainless tubing in the event of a serious chromium shortage. The process consists of the initial assembly of three component tubesets from conventionally produced tubing, the formation of a strong metallurgical bond between the three components by gas pressure bonding, and conventional cold draw and anneal processing to final size. The quality of the tubes produced was excellent from the standpoint of bond strength, mechanical, and forming properties. The only significant quality problem encountered was carburization of the stainless clad by the carbon steel core which can be overcome by further refinement through at least three different approaches. The estimated cost of clad tubing produced by this process is greater than that for monolithic stainless tubing, but not so high as to make the process impractical as a chromium conservation method.

  9. Investigations of thiosulfate accumulation on 304 stainless steel in neutral solutions by radioactive labeling, electrochemistry, Auger electron and X-ray photoelectron spectroscopy methods

    SciTech Connect

    Thomas, A.E.; Kolics, A.; Wieckowski, A. [Univ. of Illinois, Urbana, IL (United States)

    1997-02-01

    Thiosulfate accumulation on 304 stainless steel in near neutral solutions (pH {approximately}5.6) was studied using in situ techniques: electrochemistry and radiochemistry, as well as by Auger electron spectroscopy depth profiling and angle-resolved x-ray photoelectron spectroscopy in ultrahigh vacuum. It was found that thiosulfate accumulation is an irreversible process and occurs over a broad electrode potential range. Thiosulfate surface concentration is very small, below {minus}1.0 V vs. Ag/AgCl reference. In the potential range from {minus}1.0 to 0.50 V the surface concentration increases linearly with potential, reaches a maximum at {minus}0.30 V, and at even more positive potentials, decreases to a slightly lower level. Ultrahigh vacuum spectroscopic measurements indicate that the irreversible surface behavior can be attributed to thiosulfate incorporation into the substrate passive film. The present data obtained with 304 stainless steel are compared to previous results published from this laboratory on thiosulfate adsorption on 316 stainless steel, and the role of molybdenum surface enrichment in the thiosulfate accumulation reversibility is discussed. The effect of chloride on thiosulfate accumulation was also investigated. At high concentration of chloride, thiosulfate is desorbed from the surface due to chloride-induced dissolution of the stainless steel. At very negative potentials, the thiosulfate surface concentration increases upon chloride addition, most probably due to the surface microroughening caused by chloride adsorption.

  10. Standard test method for evaluating stress-corrosion cracking of stainless alloys with different nickel content in boiling acidified sodium chloride solution

    E-print Network

    American Society for Testing and Materials. Philadelphia

    2000-01-01

    1.1 This test method describes a procedure for conducting stress-corrosion cracking tests in an acidified boiling sodium chloride solution. This test method is performed in 25% (by mass ) sodium chloride acidified to pH 1.5 with phosphoric acid. This test method is concerned primarily with the test solution and glassware, although a specific style of U-bend test specimen is suggested. 1.2 This test method is designed to provide better correlation with chemical process industry experience for stainless steels than the more severe boiling magnesium chloride test of Practice G36. Some stainless steels which have provided satisfactory service in many environments readily crack in Practice G36, but have not cracked during interlaboratory testing using this sodium chloride test method. 1.3 This boiling sodium chloride test method was used in an interlaboratory test program to evaluate wrought stainless steels, including duplex (ferrite-austenite) stainless and an alloy with up to about 33% nickel. It may also b...

  11. Simultaneous chromizing-aluminizing coating of austenitic stainless steels

    Microsoft Academic Search

    D. M. Miller; S. C. Kung; S. D. Scarberry; R. A. Rapp

    1988-01-01

    Chromium and aluminum were simultaneously co-deposited by diffusion into austenitic stainless steel substrates, by a single-step, pack-cementation process. The mechanism for the formation of diffusion-coated products on 304 and 316 stainless steels and on Incoloy 800 is discussed. The morphologies of the phases formed at the surface, i.e., an external beta layer and an underlying multiphase interdiffusion zone, are presented.

  12. Surface Modification of Stainless Steels By Carbon/nitrogen Implantation

    NASA Astrophysics Data System (ADS)

    Jirásková, Y.; Schneeweiss, O.; Havlí?ek, S.; Blawert, C.; Kalvelage, H.

    2001-07-01

    Plasma immersion ion implantation has been used for simultaneous implantation of carbon and nitrogen into austenitic, ferritic, and duplex stainless steels at 400°C for 3 h. The surface phase composition, studied by means of Conversion Electron Mössbauer Spectroscopy and X-Ray difraction, is correlated with the mechanical properties represented by hardness (Vickers) measurements. The results extend information about the expanded austenite phase formed during the low temperature modification of stainless steel surface by nitrogen.

  13. Electrochemical corrosion behavior of a novel antibacterial stainless steel

    Microsoft Academic Search

    Yongqian Liu; Jibiao Li; Emeka E. Oguzie; Ying Li; Demin Chen; Ke Yang; Fuhui Wang

    2009-01-01

    A novel antibacterial stainless steel (ASS) with martenstic microstructure has been recently developed, by controlled copper ion implantation, as a new functional material having broad-spectrum antibacterial properties. The electrochemical corrosion behavior of the ASS in 0.05mol\\/L NaCl was assessed using linear polarization and electrochemical impedance spectroscopy (EIS) and compared with that of a conventional stainless steel (SS) without copper ion

  14. Corrosion testing of stainless steel-zirconium metal waste form

    Microsoft Academic Search

    1998-01-01

    Stainless steel-zirconium (SS-Zr) alloys are being considered as waste forms for the disposition of metallic waste generated during the electrometallurgical treatment of spent nuclear fuel. The waste forms contain irradiated cladding hulls, components of the alloy fuel, noble metal fission products, and actinide elements. The baseline waste form is a stainless steel-15 wt% zirconium (SS-15Zr) alloy. This article presents microstructure

  15. Corrosion resistance of stainless steel in chloride contaminated concrete

    Microsoft Academic Search

    Gu Ping; S. Elliott; J. J. Beaudoin; B. Arsenault

    1996-01-01

    The results of an investigation of the performance of 2-year-old stainless steel reinforced concrete specimens which were previously placed in an aggressive aqueous solution containing chlorides are presented. This study consisted of corrosion rate testing of reinforced concrete samples with normal reinforcing steel and stainless steel rebars by means of the a.c. impedance spectroscopy. The equivalent circuit simulation analysis method

  16. Yag laser welding of neutron irradiated stainless steels

    Microsoft Academic Search

    S. Nishimura; R. Katsura; Y. Saito; W. Kono; H. Takahashi; M. Koshiishi; T. Kato; K. Asano

    1998-01-01

    Type 304L stainless steel plates of 8 mm thickness irradiated in a boiling water reactor (BWR) to 1.2×1025 n\\/m2 (E>1.0 MeV) containing 9 appm helium from transmutation have been successfully welded using a high power Nd–YAG laser under conditions of both continuous wave (CW) and pulse modes. Unirradiated Type 316L stainless steel plate was lap welded to the irradiated Type

  17. Failure Analysis of AISI304 Stainless Steel Styrene Storage Tank

    Microsoft Academic Search

    Muhammad Sajid Ali Asghar; Fawad Tariq; Ashraf Ali

    2010-01-01

    This paper presents the failure analysis of AISI-304 stainless steel tank that was fabricated by welding and used for the\\u000a storage of styrene monomers. After about 13 years of satisfactory operation, significant cracking was observed adjacent to\\u000a the weld joints and in base plate near tank foundation. Weld repair was by shielded gas arc welding using AISI 308 stainless\\u000a steel filler

  18. X-ray attenuation properties of stainless steel (u)

    SciTech Connect

    Wang, Lily L [Los Alamos National Laboratory; Berry, Phillip C [Los Alamos National Laboratory

    2009-01-01

    Stainless steel vessels are used to enclose solid materials for studying x-ray radiolysis that involves gas release from the materials. Commercially available stainless steel components are easily adapted to form a static or a dynamic condition to monitor the gas evolved from the solid materials during and after the x-ray irradiation. Experimental data published on the x-ray attenuation properties of stainless steel, however, are very scarce, especially over a wide range of x-ray energies. The objective of this work was to obtain experimental data that will be used to determine how a poly-energetic x-ray beam is attenuated by the stainless steel container wall. The data will also be used in conjunction with MCNP (Monte Carlos Nuclear Particle) modeling to develop an accurate method for determining energy absorbed in known solid samples contained in stainless steel vessels. In this study, experiments to measure the attenuation properties of stainless steel were performed for a range of bremsstrahlung x-ray beams with a maximum energy ranging from 150 keV to 10 MeV. Bremsstrahlung x-ray beams of these energies are commonly used in radiography of engineering and weapon components. The weapon surveillance community has a great interest in understanding how the x-rays in radiography affect short-term and long-term properties of weapon materials.

  19. Nickel release from nickel-plated metals and stainless steels.

    PubMed

    Haudrechy, P; Foussereau, J; Mantout, B; Baroux, B

    1994-10-01

    Nickel release from nickel-plated metals often induces allergic contact dermatitis, but, for nickel-containing stainless steels, the effect is not well-known. In this paper, AISI 304, 316L, 303 and 430 type stainless steels, nickel and nickel-plated materials were investigated. 4 tests were performed: patch tests, leaching experiments, dimethylglyoxime (DMG) spot tests and electrochemical tests. Patch tests showed that 96% of the patients were intolerant to Ni-plated samples, and 14% to a high-sulfur stainless steel (303), while nickel-containing stainless steels with a low sulfur content elicited no reactions. Leaching experiments confirmed the patch tests: in acidic artificial sweat, Ni-plated samples released about 100 micrograms/cm2/week of nickel, while low-sulfur stainless steels released less than 0.03 microgram/cm2/week of nickel, and AISI 303 about 1.5 micrograms/cm2/week. Attention is drawn to the irrelevance of the DMG spot test, which reveals Ni present in the metal bulk but not its dissolution rate. Electrochemical experiments showed that 304 and 316 grades remain passive in the environments tested, while Ni-plated steels and AISI 303 can suffer significant cation dissolution. Thus, Ni-containing 304 and 316 steels should not induce contact dermatitis, while 303 should be avoided. A reliable nitric acid spot test is proposed to distinguish this grade from other stainless steels. PMID:7842681

  20. Growth kinetics and photoelectrochemical (PEC) performance of cadmium selenide thin films: pH and substrate effect

    Microsoft Academic Search

    Y. G. Gudage; Ramphal Sharma

    2010-01-01

    Cadmium selenide (CdSe) thin films have been electrochemically deposited on the stainless steel (SS) and fluorine-doped tin oxide (FTO) coated glass substrates at room temperature (27°C). The growth kinetics of CdSe thin films was studied by using cyclic voltammetry and chronoamperometry with variation in the pH of the electrolytic bath. In addition, the influence of the substrate on the microstructural

  1. 50 CFR 17.7 - Raptor exemption.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...a live migratory bird of the Order Falconiformes or the Order Strigiformes, other than a bald eagle (Haliaeetus leucocephalus ) or a golden eagle (Aquila chrysaetos )] legally held in captivity or in a controlled environment...

  2. 50 CFR 17.7 - Raptor exemption.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...a live migratory bird of the Order Falconiformes or the Order Strigiformes, other than a bald eagle (Haliaeetus leucocephalus ) or a golden eagle (Aquila chrysaetos )] legally held in captivity or in a controlled environment...

  3. 50 CFR 17.7 - Raptor exemption.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...a live migratory bird of the Order Falconiformes or the Order Strigiformes, other than a bald eagle (Haliaeetus leucocephalus ) or a golden eagle (Aquila chrysaetos )] legally held in captivity or in a controlled environment...

  4. 50 CFR 17.7 - Raptor exemption.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...a live migratory bird of the Order Falconiformes or the Order Strigiformes, other than a bald eagle (Haliaeetus leucocephalus ) or a golden eagle (Aquila chrysaetos )] legally held in captivity or in a controlled environment...

  5. 50 CFR 17.7 - Raptor exemption.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...a live migratory bird of the Order Falconiformes or the Order Strigiformes, other than a bald eagle (Haliaeetus leucocephalus ) or a golden eagle (Aquila chrysaetos )] legally held in captivity or in a controlled environment...

  6. 36 CFR 17.7 - Preference rights.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...property which has been in Federal ownership less than two years, the Secretary, in addition to the notice specified in § 17.4, shall inform the last owner or owners of record by certified mail at their present or last known address of the...

  7. Phase Transformations in Cast Duplex Stainless Steels

    SciTech Connect

    Yoon-Jun Kim

    2004-12-19

    Duplex stainless steels (DSS) constitute both ferrite and austenite as a matrix. Such a microstructure confers a high corrosion resistance with favorable mechanical properties. However, intermetallic phases such as {sigma} and {chi} can also form during casting or high-temperature processing and can degrade the properties of the DSS. This research was initiated to develop time-temperature-transformation (TTT) and continuous-cooling-transformation (CCT) diagrams of two types of cast duplex stainless steels, CD3MN (Fe-22Cr-5Ni-Mo-N) and CD3MWCuN (Fe-25Cr-7Ni-Mo-W-Cu-N), in order to understand the time and temperature ranges for intermetallic phase formation. The alloys were heat treated isothermally or under controlled cooling conditions and then characterized using conventional metallographic methods that included tint etching, and also using electron microscopy (SEM, TEM) and wavelength dispersive spectroscopy (WDS). The kinetics of intermetallic-phase ({sigma} + {chi}) formation were analyzed using the Johnson-Mehl-Avrami (MA) equation in the case of isothermal transformations and a modified form of this equation in the case of continuous cooling transformations. The rate of intermetallic-phase formation was found to be much faster in CD3MWCuN than CD3MN due mainly to differences in the major alloying contents such as Cr, Ni and Mo. To examine in more detail the effects of these elements of the phase stabilities; a series of eight steel castings was designed with the Cr, Ni and Mo contents systematically varied with respect to the nominal composition of CD3MN. The effects of varying the contents of alloying additions on the formation of intermetallic phases were also studied computationally using the commercial thermodynamic software package, Thermo-Calc. In general, {sigma} was stabilized with increasing Cr addition and {chi} by increasing Mo addition. However, a delicate balance among Ni and other minor elements such as N and Si also exists. Phase equilibria in DSS can be affected by local composition fluctuations in the cast alloy. This may cause discrepancy between thermodynamic prediction and experimental observation.

  8. ESTUDIO DE LA ROTURA DE UN CONJUNTO DE ARANDELAS

    Microsoft Academic Search

    G. Atxaga; A. Pelayo; Irisarri FUNDACIÓN; San Sebastián

    This paper analyses the failure of a set of washers, broken in service in a seawater environment and a high temperature. These parts were manufactured using a 17-7 PH, UNS S17700 precipitation hardening stainless steel. The morphology of the cracks was intergranular and it was attributed to hydrogen embrittlement due to the hydrogen that entered into the steel during the

  9. Instabilities in stabilized austenitic stainless steels

    NASA Astrophysics Data System (ADS)

    Ayer, Raghavan; Klein, C. F.; Marzinsky, C. N.

    1992-09-01

    The effect of aging on the precipitation of grain boundary phases in three austenitic stainless steels (AISI 347, 347AP, and an experimental steel stabilized with hafnium) was investigated. Aging was performed both on bulk steels as well as on samples which were subjected to a thermal treatment to simulate the coarse grain region of the heat affected zone (HAZ) during welding. Aging of the bulk steels at 866 K for 8000 hours resulted in the precipitation of Cr23C6 carbides, ?, and Fe2Nb phases; the propensity for precipitation was least for the hafnium-stabilized steel. Weld simulation of the HAZ resulted in dissolution of the phases present in the as-received 347 and 347AP steels, leading to grain coarsening. Subsequent aging caused extensive grain boundary Cr23C6 carbides and inhomogeneous matrix precipitation. In addition, steel 347AP formed a precipitate free zone (PFZ) along the grain boundaries. The steel containing hafnium showed the best microstructural stability to aging and welding.

  10. NanoComposite Stainless Steel Powder Technologies

    SciTech Connect

    DeHoff, R.; Glasgow, C. (MesoCoat, Inc.)

    2012-07-25

    Oak Ridge National Laboratory has been investigating a new class of Fe-based amorphous material stemming from a DARPA, Defense Advanced Research Projects Agency initiative in structural amorphous metals. Further engineering of the original SAM materials such as chemistry modifications and manufacturing processes, has led to the development of a class of Fe based amorphous materials that upon processing, devitrify into a nearly homogeneous distribution of nano sized complex metal carbides and borides. The powder material is produced through the gas atomization process and subsequently utilized by several methods; laser fusing as a coating to existing components or bulk consolidated into new components through various powder metallurgy techniques (vacuum hot pressing, Dynaforge, and hot isostatic pressing). The unique fine scale distribution of microstructural features yields a material with high hardness and wear resistance compared to material produced through conventional processing techniques such as casting while maintaining adequate fracture toughness. Several compositions have been examined including those specifically designed for high hardness and wear resistance and a composition specifically tailored to devitrify into an austenitic matrix (similar to a stainless steel) which poses improved corrosion behavior.

  11. Radiation-induced swelling of stainless steel.

    PubMed

    Shewmon, P G

    1971-09-10

    Significant swelling (1 to 10 percent due to small voids have been found in stainless steel when it is exposed to fast neutron doses less than expected in commercial fast breeder reactors. The main features of this new effect are: (i) the voids are formed by the precipitation of a small fraction of the radiation-produced vacancies; (ii) the voids form primarily in the temperature range 400 degrees to 600 degrees C (750 degrees to 1100 degrees F); and (iii) the volume increases with dose (fluence) at a rate between linear and parabolic. The limited temperature range of void formation can be explained, but the effects of fluence, microstructure, and composition are determined by a competition between several kinetic processes that are not well understood. This swelling does not affect the feasibility or safety of the breeder reactor,but will have a significant impact on the core design and economics of the breeder.Preliminary results indicate that one cannot eliminate the effect,but cold-working,heat treatment, or small changes in composition can reduce the swelling by a factor of 2 or more. Testing is hampered by the fact that several years in EBR-II are required to accumulate the fluence expected in demonstration plants. Heavyion accelerators,which allow damage rates corresponding to much higher fluxes than those found in EBR-II,hold great promise for short-term tests that will indicate the relative effect of the important variables. PMID:17796573

  12. Austenitic stainless steel for high temperature applications

    DOEpatents

    Johnson, Gerald D. (Kennewick, WA); Powell, Roger W. (Pasco, WA)

    1985-01-01

    This invention describes a composition for an austenitic stainless steel which has been found to exhibit improved high temperature stress rupture properties. The composition of this alloy is about (in wt. %): 12.5 to 14.5 Cr; 14.5 to 16.5 Ni; 1.5 to 2.5 Mo; 1.5 to 2.5 Mn; 0.1 to 0.4 Ti; 0.02 to 0.08 C; 0.5 to 1.0 Si; 0.01 maximum, N; 0.02 to 0.08 P; 0.002 to 0.008 B; 0.004-0.010 S; 0.02-0.05 Nb; 0.01-0.05 V; 0.005-0.02 Ta; 0.02-0.05 Al; 0.01-0.04 Cu; 0.02-0.05 Co; 0.03 maximum, As; 0.01 maximum, O; 0.01 maximum, Zr; and with the balance of the alloy being essentially iron. The carbon content of the alloy is adjusted such that wt. % Ti/(wt. % C+wt. % N) is between 4 and 6, and most preferably about 5. In addition the sum of the wt. % P+wt. % B+wt. % S is at least 0.03 wt. %. This alloy is believed to be particularly well suited for use as fast breeder reactor fuel element cladding.

  13. Welding Behavior of Free Machining Stainless Steel

    SciTech Connect

    BROOKS,JOHN A.; ROBINO,CHARLES V.; HEADLEY,THOMAS J.; MICHAEL,JOSEPH R.

    2000-07-24

    The weld solidification and cracking behavior of sulfur bearing free machining austenitic stainless steel was investigated for both gas-tungsten arc (GTA) and pulsed laser beam weld processes. The GTA weld solidification was consistent with those predicted with existing solidification diagrams and the cracking response was controlled primarily by solidification mode. The solidification behavior of the pulsed laser welds was complex, and often contained regions of primary ferrite and primary austenite solidification, although in all cases the welds were found to be completely austenite at room temperature. Electron backscattered diffraction (EBSD) pattern analysis indicated that the nature of the base metal at the time of solidification plays a primary role in initial solidification. The solid state transformation of austenite to ferrite at the fusion zone boundary, and ferrite to austenite on cooling may both be massive in nature. A range of alloy compositions that exhibited good resistance to solidification cracking and was compatible with both welding processes was identified. The compositional range is bounded by laser weldability at lower Cr{sub eq}/Ni{sub eq} ratios and by the GTA weldability at higher ratios. It was found with both processes that the limiting ratios were somewhat dependent upon sulfur content.

  14. 77 FR 42697 - Stainless Steel Butt-Weld Pipe Fittings From Italy, Malaysia, and the Philippines: Continuation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-20

    ...titled Stainless Steel Butt-Weld Pipe Fittings...is certain stainless steel butt-weld pipe fittings...product encompasses all grades of stainless steel and ``commodity...Fittings, or its foreign equivalents (e.g., DIN or...

  15. 77 FR 24459 - Stainless Steel Butt-Weld Pipe Fittings From Italy: Final Results of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-24

    ...1\\ See Stainless Steel Butt-Weld Pipe Fittings...is certain stainless steel, butt-weld pipe fittings...product encompasses all grades of stainless steel and ``commodity...Fittings, or its foreign equivalents (e.g., DIN or...

  16. 76 FR 38688 - Certain Welded Stainless Steel Pipe From Korea and Taiwan; Institution of a Five-Year Review...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-01

    ...A-778 stainless steel pipes. (4) The...of welded stainless steel pipes and pressure tubes, excluding grade 409 tubes and mechanical...A-778 stainless steel pipes. For purposes...which it can provide equivalent information. If...

  17. Irradiation resistance of a nanostructured 316 austenitic stainless steel

    NASA Astrophysics Data System (ADS)

    Revathy Rajan, P. B.; Monnet, I.; Hug, E.; Etienne, A.; Enikeev, N.; Keller, C.; Sauvage, X.; Valiev, R.; Radiguet, B.

    2014-08-01

    The reduction of grain size down to several tens or hundreds of nanometers leads to the enhancement of radiation resistance of metals. Based on this approach, the aim of the Labex EMC3 (Energy Materials and Clean Combustion Center) project "Naninox" is (1) to study the stability of the microstructure of a nanostructured 316 stainless steel under ion irradiation and (2) to link between this microstructure and the properties (corrosion resistance and the microhardness) of the steel (thanks to a better irradiation resistance, a better corrosion resistance and higher mechanical properties after irradiation are expected in the ultra-fine grained stainless steel). Ultrafine grained 316L austenitic stainless steel samples have been produced by high pressure torsion (HPT) at 430°C and then ion irradiated in Jannus facilities (CEA Saclay) at 450°C and 5 displacements per atoms (dpa). Their microstructure is characterized before and after irradiation by atom probe tomography, X-ray diffraction and transmission electron microscopy. Corrosion behavior in NaCl solution is tested and nano-indentation tests are performed. The first results obtained by atom probe tomography described in this paper indicate that the microstructure of ultrafine grain 316 austenitic stainless steel is more stable under irradiation than the microstructure of a coarse grain 316 austenitic stainless steel.

  18. Investigation of the diffusion kinetics of borided stainless steels

    NASA Astrophysics Data System (ADS)

    Kayali, Yusuf

    2013-12-01

    In this study, the kinetics of borides formed on AISI 420, AISI 304 and AISI 304L stainless steels was investigated. Boronizing treatment was carried out using Ekabor-II powders at the processing temperatures of 1123, 1173 and 1223 K for 2, 4 and 6 h. The phases of the boride layers of borided AISI 420, AISI 304 and AISI 304L stainless steels were FeB, Fe2B, CrB and NiB, respectively. The thickness of the boride layer formed on the borided steels ranged from 4.6 to 64 ?m depending on the boriding temperature, boriding time and alloying elements of the stainless steels. Depending on the chemical composition, temperature and layer thickness, the activation energies of boron in AISI 420, AISI 304 and AISI 304L stainless steels were found to be 206.161, 234.641 and 222.818 kJ/mol, respectively. The kinetics of growth of the boride layers formed on the AISI 420, AISI 304 and AISI 304L stainless steels and the thickness of the boride layers were investigated.

  19. Aging of cast duplex stainless steels in LWR systems

    SciTech Connect

    Chopra, O.K.; Chung, H.M.

    1984-10-01

    A program is being conducted to investigate the significance of in-service embrittlement of cast duplex stainless steels under light-water reactor operating conditions. The existing data are evaluated to determine the expected embrittlement of cast components during the operating lifetime of reactors and to define the objectives and scope of the investigation. This presentation describes the status of the program. Data for the metallurgical characterization of the various cast stainless steels used in the investigation are presented. Charpy impact tests on short-term aged material indicate that CF-3 stainless steels are less susceptible to embrittlement than CF-8 or CF-8M stainless steels. Microstructural characterization of cast stainless steels that were obtained from Georg Fischer Co. and aged for up to 70,000 h at 300, 350, and 400/sup 0/C reveals the formation of four different types of precipitates that are not ..cap alpha..'. Embrittlement of the ferrite phase is primarily due to pinning of the dislocations by two of these precipitates, designated as Type M and Type X. The ferrite phase is embrittled after approx. 8 y at 300/sup 0/C and shows cleavage fracture. Examination of the fracture surfaces of the impact-test specimens indicates that the toughness of the long-term aged material is determined by the austenite phase. 8 figures, 3 tables.

  20. Antibacterial effect of silver nanofilm modified stainless steel surface

    NASA Astrophysics Data System (ADS)

    Fang, F.; Kennedy, J.; Dhillon, M.; Flint, S.

    2015-03-01

    Bacteria can attach to stainless steel surfaces, resulting in the colonization of the surface known as biofilms. The release of bacteria from biofilms can cause contamination of food such as dairy products in manufacturing plants. This study aimed to modify stainless steel surfaces with silver nanofilms and to examine the antibacterial effectiveness of the modified surface. Ion implantation was applied to produce silver nanofilms on stainless steel surfaces. 35 keV Ag ions were implanted with various fluences of 1 × 1015 to 1 × 1017 ions•cm-2 at room temperature. Representative atomic force microscopy characterizations of the modified stainless steel are presented. Rutherford backscattering spectrometry spectra revealed the implanted atoms were located in the near-surface region. Both unmodified and modified stainless steel coupons were then exposed to two types of bacteria, Pseudomonas fluorescens and Streptococcus thermophilus, to determine the effect of the surface modification on bacterial attachment and biofilm development. The silver modified coupon surface fluoresced red over most of the surface area implying that most bacteria on coupon surface were dead. This study indicates that the silver nanofilm fabricated by the ion implantation method is a promising way of reducing the attachment of bacteria and delay biofilm formation.

  1. Work of adhesion of dairy products on stainless steel surface

    PubMed Central

    Bernardes, Patrícia Campos; Araújo, Emiliane Andrade; dos Santos Pires, Ana Clarissa; Queiroz Fialho Júnior, José Felício; Lelis, Carini Aparecida; de Andrade, Nélio José

    2012-01-01

    The adhesion of the solids presents in food can difficult the process of surface cleaning and promotes the bacterial adhesion process and can trigger health problems. In our study, we used UHT whole milk, chocolate based milk and infant formula to evaluate the adhesion of Enterobacter sakazakii on stainless steel coupons, and we determine the work of adhesion by measuring the contact angle as well as measured the interfacial tension of the samples. In addition we evaluated the hydrophobicity of stainless steel after pre-conditioning with milk samples mentioned. E. sakazakii was able to adhere to stainless steel in large numbers in the presence of dairy products. The chocolate based milk obtained the lower contact angle with stainless steel surface, higher interfacial tension and consequently higher adhesion work. It was verified a tendency of decreasing the interfacial tension as a function of the increasing of protein content. The preconditioning of the stainless steel coupons with milk samples changed the hydrophobic characteristics of the surfaces and became them hydrophilic. Therefore, variations in the composition of the milk products affect parameters important that can influence the procedure of hygiene in surface used in food industry. PMID:24031951

  2. Ph.D. Astronomy Program Ph.D. in Astronomy

    E-print Network

    Hemmers, Oliver

    Ph.D. Astronomy Program Ph.D. in Astronomy Department(s) Physics and Astronomy College Sciences 1 physics at the graduate level 4. understand observational astronomy techniques 5. understand astrophysics strong background of knowledge and expertise in physics and astronomy #12;2. Curriculum Alignment

  3. Persistence of spiromesifen in soil: influence of moisture, light, pH and organic amendment.

    PubMed

    Mate, Ch Jamkhokai; Mukherjee, Irani; Das, Shaon Kumar

    2015-02-01

    Persistence of spiromesifen in soil as affected by varying moisture, light, compost amendment, soil sterilization and pH in aqueous medium were studied. Degradation of spiromesifen in soil followed the first-order reaction kinetics. Effect of different moisture regimes indicated that spiromesifen dissipated faster in submerged soil (t 1/2 14.3-16.7 days) followed by field capacity (t 1/2 18.7-20.0 days), and dry soil (t 1/2 21.9-22.9 days). Dissipation was faster in sterilized submerged (t 1/2 17.7 days) than in sterilized dry (t 1/2 35.8 days). Photo spiromesifen metabolite was not detected under different moisture regimes. After 30 days, enol spiromesifen metabolite was detected under submerged condition and was below detectable limit (<0.001 ?g g(-1)) after 90 days. Soil amendment compost (2.5 %) at field capacity enhanced dissipation of the insecticide, and half-life value was 14.3 against 22.4 days without compost amendment. Under different pH condition, residues persisted in water with half-life values 5.7 to 12.5 days. Dissipation in water was faster at pH 9.0 (t 1/2 5.7 days), followed by pH 4.0 (t 1/2 9.7 days) and pH 7.2 (t 1/2 12.5 days). Exposure of spiromesifen to different light conditions indicated that it was more prone to degradation under UV light (t 1/2 3-4 days) than sunlight exposure (t 1/2 5.2-8.1 days). Under sunlight exposure, photo spiromesifen metabolite was detected after 10 and 15 days as compared to 3 and 5 days under UV light exposure. PMID:25616783

  4. 77 FR 58355 - Drawn Stainless Steel Sinks From the People's Republic of China: Countervailing Duty Investigation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-20

    ...see Drawn Stainless Steel Sinks From the People's Republic of China: Initiation of Antidumping Duty Investigation, 77 FR 18207 (March 27, 2012). \\2\\ See Drawn Stainless Steel Sinks From the People's Republic of China: Preliminary...

  5. Aluminum and stainless steel tubes joined by simple ring and welding process

    NASA Technical Reports Server (NTRS)

    Townhill, A.

    1967-01-01

    Duranel ring is used to join aluminum and stainless steel tubing. Duranel is a bimetal made up of roll-bonded aluminum and stainless steel. This method of joining the tubing requires only two welding operations.

  6. Machining-induced deformation in stepped specimens of PH 13-8 Mo, 18 nickel maraging steel grade 200T1 and grain-refined HP 9-4-20

    NASA Technical Reports Server (NTRS)

    Wigley, D. A.

    1985-01-01

    The results of a study to evaluate the dimensional changes created during machining and subsequent cycling to cryogenic temperatures for three different metallic alloys are presented. Experimental techniques are described and results presented for 18 Ni Grade 200 maraging steel, PH-13-8 Mo stainless steel, and Grain-refined HP 9-4-20.

  7. Jacob Bernoulli, Ph.D. Erhard Weigel, Ph.D. Universitt Leipzig 1650

    E-print Network

    Matta, Abraham "Ibrahim"

    Jacob Bernoulli, Ph.D. Erhard Weigel, Ph.D. Universität Leipzig 1650 Gottfried Wilhelm Leibniz, Dr. jur. Universität Altdorf 1666 Johann Bernoulli, Ph.D. 1694 Leonhard Euler, Ph.D. Universität Basel 1726 Joseph Louis Lagrange, Ph.D. Simeon Denis Poisson, Ph.D. Jean-Baptiste Joseph Fourier, Ph

  8. Keiji TANAKA, Ph.D. Hitoshi OKAMOTO, M.D., Ph.D.

    E-print Network

    Kazama, Hokto

    Keiji TANAKA, Ph.D. Hitoshi OKAMOTO, M.D., Ph.D. Atsushi MIYAWAKI, M.D., Ph.D. Tadaharu TSUMOTO, M.D., Ph.D. Shin OHKOUCHI Masao ITO, M.D., Ph.D. Shun-ichi AMARI, D.Eng. Susumu TONEGAWA, Ph Committee Senior Advisor Charles YOKOYAMA, Ph.D. Neural Circuit Function Developmental Gene Regulation

  9. Influence of surface roughness of stainless steel on microbial adhesion and corrosion resistance

    Microsoft Academic Search

    Lisbeth R. Hilbert; Dorthe Bagge-Ravn; John Kold; Lone Gram

    2003-01-01

    The aim of this study was to evaluate whether hygienic characteristics of stainless steel used in the food industry could be improved by smoothing surface roughness (Ra) from Ra 0.9–0.01?m. The adherence of Pseudomonas sp., Listeria monocytogenes and Candida lipolytica, to stainless steel was not affected by surface roughness ranging from grit 4000 polished stainless steel (Ra<0.01) to ground stainless

  10. Low-Temperature Aging Characteristics of Type 316L Stainless Steel Welds: Dependence on Solidification Mode

    Microsoft Academic Search

    Hiroshi Abe; Yutaka Watanabe

    2008-01-01

    Thermal aging embrittlement of light water reactor (LWR) components made of stainless steel cast has been recognized as a\\u000a potential degradation issue, and careful attention has been paid to it. Although welds of austenitic stainless steels have\\u000a ?-? duplex microstructure, which is similar to that of the stainless steel cast, examination of the thermal aging characteristics\\u000a of the stainless steel

  11. Final Report, Volume 1, Metallurgical Evaluation of Cast Duplex Stainless Steels and their Weldments

    Microsoft Academic Search

    Songqing Wen; Carl Lundin; Greg Batten

    2005-01-01

    Duplex stainless steels (DSS) are being specified for chloride containing environments due to their enhanced pitting and stress corrosion cracking resistance. They exhibit improved corrosion performance over the austenitic stainless steels. Duplex stainless steels also offer improved strength properties and are available in various wrought and cast forms. ;\\u000a\\u0009Selected grades of duplex stainless steel castings and their welds, in

  12. Corrosion of annealed AISI 316 stainless steel in sodium environment

    NASA Astrophysics Data System (ADS)

    Ganesan, Vaidehi; Ganesan, Vedaraman

    1998-07-01

    Solution annealed AISI type 316 austenitic stainless steel specimens were exposed in static sodium at 773 and 873 K for durations ranging from 500 to 2000 h. The results, i.e, weight loss data, hardness values, carburisation, depletion rates, sigma phase formation from the ferrite layer, corrosion morphology, roughness values etc. are analysed and discussed in the paper. Corrosion data such as the weight loss/depleted layer thickness and microstructure of fully annealed stainless steel specimens at 773 and 873 K under static sodium conditions (present study) are comparable to those of 20% cold worked stainless steel type 316 specimens at temperatures 973 K and above under dynamic sodium conditions. Annealed specimens leach out at a faster rate than cold worked specimens exposed to sodium.

  13. Swelling susceptibility of electron-beam welded austenitic stainless steel

    NASA Astrophysics Data System (ADS)

    Sawai, T.; Fukai, K.; Hamada, S.; Suzuki, K.; Hishinuma, A.

    1986-11-01

    The void swelling susceptibility of austenitic stainless steel weldments has been examined. Materials used were Type 316 stainless steel containing 0.08% Ti and JPCA. Plates of these steels were electron-beam welded in a vacuum, and disks for irradiation experiments were obtained from the transverse sections, corresponding to the base metal, heat affected zone and weld metal. Irradiation in a High Voltage Electron Microscope (HVEM) was carried out at 773 K up to 15 dpa. In both steels this produced more void swelling in the weld metal than in the base metal, and more void swelling in the heat affected zone than in the base metal for Type 316 stainless steel. Segregation during solidification was detected in the weld metal and this may affect the void swelling susceptibility through the compositional change along with precipitation.

  14. Practical handbook of stainless steels and nickel alloys

    SciTech Connect

    Lamb, S. [ed.

    1999-07-01

    This new handbook is an up-to-date technical guide to the grades, properties, fabrication characteristics, and applications of stainless steels and nickel alloys. The individual chapters were written by industry experts and focus on the key properties and alloy characteristics important in material selection and specification as well as the practical factors that influence the development and application of these materials. The contents include: alloy grades and their welding and fabrication characteristics and their application; monel metal; iron-based and nickel-based alloys; ferritic, austenitic, superaustenitic, and martensitic stainless steels; hastelloys; alloys 20, G, and 825; AOD and new refining technology; duplex stainless steels; 6-Mo alloys; corrosion-resistant castings; specification cross-reference tables; trade names; hardness conversions; list of common abbreviations.

  15. Machinability of a Stainless Steel by Electrochemical Discharge Microdrilling

    NASA Astrophysics Data System (ADS)

    Cotea??, Margareta; Schulze, Hans-Peter; Pop, Nicolae; Be?liu, Irina; Sl?tineanu, Lauren?iu

    2011-05-01

    Due to the chemical elements included in their structure for ensuring an increased resistance to the environment action, the stainless steels are characterized by a low machinability when classical machining methods are applied. For this reason, sometimes non-traditional machining methods are applied, one of these being the electrochemical discharge machining. To obtain microholes and to evaluate the machinability by electrochemical discharge microdrilling, test pieces of stainless steel were used for experimental research. The electrolyte was an aqueous solution of sodium silicate with different densities. A complete factorial plan was designed to highlight the influence of some input variables on the sizes of the considered machinability indexes (electrode tool wear, material removal rate, depth of the machined hole). By mathematically processing of experimental data, empirical functions were established both for stainless steel and carbon steel. Graphical representations were used to obtain more suggestive vision concerning the influence exerted by the considered input variables on the size of the machinability indexes.

  16. The pH Game.

    ERIC Educational Resources Information Center

    Chemecology, 1996

    1996-01-01

    Describes a game that can be used to teach students about the acidity of liquids and substances around their school and enable them to understand what pH levels tell us about the environment. Students collect samples and measure the pH of water, soil, plants, and other natural material. (DDR)

  17. PhEDEx Data Service

    Microsoft Academic Search

    Ricky Egeland; Tony Wildish; Chih-Hao Huang

    2010-01-01

    The PhEDEx Data Service provides access to information from the central PhEDEx database, as well as certificate-authenticated managerial operations such as requesting the transfer or deletion of data. The Data Service is integrated with the \\

  18. An investigation of the typical corrosion parameters used to test polymer electrolyte fuel cell bipolar plate coatings, with titanium nitride coated stainless steel as a case study

    NASA Astrophysics Data System (ADS)

    Orsi, A.; Kongstein, O. E.; Hamilton, P. J.; Oedegaard, A.; Svenum, I. H.; Cooke, K.

    2015-07-01

    Stainless steel bipolar plates (BPP) for polymer electrolyte membrane fuel cells (PEMFCs) have good manufacturability, durability and low costs, but inadequate corrosion resistance and elevated interfacial contact resistance (ICR) in the fuel cell environment. Thin film coatings of titanium nitride (TiN) of 1 ?m in thickness, were deposited by means of physical vapour deposition (PVD) process on to stainless steel (SS) 316L substrates and were evaluated, in a series of tests, for their level of corrosion protection and ICR. In the ex-situ corrosion tests, variables such as applied potential, experimental duration and pH of the sulphate electrolyte at 80 °C were altered. The ICR values were found to increase after exposure to greater applied potentials and electrolytes of a higher pH. In terms of experimental duration, the ICR increased most rapidly at the beginning of each experiment. It was also found that the oxidation of TiN was accelerated after exposure to electrolytes of a higher pH. When coated BPPs were incorporated into an accelerated fuel cell test, the degradation of the fuel cell cathode resembled the plates that were tested at the highest anodic potential (1.4 VSHE).

  19. Author's personal copy Magnetic properties of stainless steels at room and cryogenic temperatures

    E-print Network

    Oxley, Paul

    Author's personal copy Magnetic properties of stainless steels at room and cryogenic temperatures: Magnetic measurement Ferromagnetic property Stainless steel Martensitic Ferritic a b s t r a c t The magnetic properties of ten types of ferritic and martensitic stainless steels have been measured at room

  20. Fatigue strength of spot welded stainless sheet steels exposed to 3% NaCl solution

    Microsoft Academic Search

    Jan Linder; Arne Melander

    1998-01-01

    Fatigue properties of spot welded stainless sheets steels have been investigated in a 3% NaCl solution and, for comparison, also in air at ambient temperature. Corrosion fatigue tests have been conducted both for one austenitic stainless steel type AISI304, and for one duplex (?50% austenite, 50% ferrite) stainless steel SAF2304. For the duplex steel, the effect of preexposure of unloaded

  1. PublishedbyManeyPublishing(c)IOMCommunicationsLtd Stainless steel weld metal designed to

    E-print Network

    Cambridge, University of

    PublishedbyManeyPublishing(c)IOMCommunicationsLtd Stainless steel weld metal designed to mitigate design methods have been used to create a stainless steel welding consumable which solidifies as d to be significantly better than commercially available martensitic stainless steel welding consumables, and it has

  2. Surface microstructures and antimicrobial properties of copper plasma alloyed stainless steel

    Microsoft Academic Search

    Xiangyu Zhang; Xiaobo Huang; Li Jiang; Yong Ma; Ailan Fan; Bin Tang

    Bacterial adhesion to stainless steel surfaces is one of the major reason causing the cross-contamination and infection in many practical applications. An approach to solve this problem is to enhance the antibacterial properties on the surface of stainless steel. In this paper, novel antibacterial stainless steel surfaces with different copper content have been prepared by a plasma surface alloying technique

  3. Fabrication of high nitrogen austenitic stainless steels with excellent mechanical and pitting corrosion properties

    Microsoft Academic Search

    Hua-bing Li; Zhou-hua Jiang; Yang Cao; Zu-rui Zhang

    2009-01-01

    A series of high nitrogen austenitic stainless steels were successfully developed with a pressurized electroslag remelting furnace. Nitride additives and deoxidizer were packed into the stainless steel pipes, and then the stainless steel pipes were welded on the surface of an electrode with low nitrogen content to prepare a compound electrode. Using Si3N4 as a nitrogen alloying source, the silicon

  4. Hot cracking susceptibility in laser weld metal of high nitrogen stainless steels

    Microsoft Academic Search

    K. Nishimoto; H. Mori

    2004-01-01

    High nitrogen stainless steels are used as structural materials required to possess high strength and fracture toughness at low temperatures. The solidification mode in weld metals of stainless steels is generally designed to be the primary ferrite solidification mode to prevent hot cracking. The weld metals in some high nitrogen stainless steels, however, exhibit the primary austenite solidification mode because

  5. Corrosion Behavior of Austenitic and Duplex Stainless Steels in Lithium Bromide

    Microsoft Academic Search

    Ayo Samuel AFOLABI; K. K. ALANEME; Samson Oluwaseyi BADA

    2009-01-01

    The corrosion behavior of austenitic and duplex stainless steels in various concentrations of lithium, bromide solution was investigated by using the conventional weight loss measurement method. The results obtained show that corrosion of these steels occurred due to the aggressive bromide ion in the medium. Duplex stainless steel shows a greater resistance to corrosion than austenitic stainless steel in the

  6. Stress corrosion cracking of sensitized austenitic stainless steels in Kuwait petroleum refineries

    Microsoft Academic Search

    A. Almubarak; M. Belkharchouche; A. Hussain

    2010-01-01

    Purpose – The purpose of this paper is to investigate stress corrosion cracking (SCC) for 304, 316, and 321 stainless steels in petroleum-processing environments. Design\\/methodology\\/approach – Sensitized austenitic stainless steels were subjected to a microstructure investigation and electrochemical test. Stressed sensitized 304, 316, and 321 stainless steels were selected and subjected to various environments that included polythionic acid, sour solution,

  7. Ozone decay on stainless steel and sugarcane bagasse surfaces

    NASA Astrophysics Data System (ADS)

    Souza-Corrêa, Jorge A.; Oliveira, Carlos; Amorim, Jayr

    2013-07-01

    Ozone was generated using dielectric barrier discharges at atmospheric pressure to treat sugarcane bagasse for bioethanol production. It was shown that interaction of ozone molecules with the pretreatment reactor wall (stainless steel) needs to be considered during bagasse oxidation in order to evaluate the pretreatment efficiency. The decomposition coefficients for ozone on both materials were determined to be (3.3 ± 0.2) × 10-8 for stainless steel and (2.0 ± 0.3) × 10-7 for bagasse. The results have indicated that ozone decomposition has occurred more efficiently on the biomass material.

  8. From flint to stainless steel: observations on surgical instrument composition.

    PubMed Central

    Kirkup, J.

    1993-01-01

    Man's failure to extract deeply embedded thorns and arrowheads, with bare hands and teeth, stimulated 'instrument substitutes' mimicking these appendages. Evidence from primitive communities suggest animal, plant and mineral items were employed, both before and after metal became the standard material of today's armamentarium. Changing surgical instrument composition has mirrored concurrent technology and manufacturing methods both of which are reviewed. Particular significance is accorded flint, bronze, crucible steel, thermal sterilisation, nickel-plate, stainless steel and disposable plastics. The paper is based on an exhibition From Flint to Stainless Steel on display at the College. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:8215156

  9. Simultaneous chromizing-aluminizing coating of austenitic stainless steels

    SciTech Connect

    Miller, D.M.; Kung, S.C.; Scarberry, S.D.; Rapp, R.A.

    1988-04-01

    Chromium and aluminum were simultaneously co-deposited by diffusion into austenitic stainless steel substrates, by a single-step, pack-cementation process. The mechanism for the formation of diffusion-coated products on 304 and 316 stainless steels and on Incoloy 800 is discussed. The morphologies of the phases formed at the surface, i.e., an external beta layer and an underlying multiphase interdiffusion zone, are presented. The formation of the brittle, ..beta.., outer layer was minimized by variations in the pack composition and activator. The coated 304 and 316 steels exhibited excellent scaling resistance upon oxidation in air at 1000/degrees/C.

  10. Microstructure and texture of Nb + Ti stabilized ferritic stainless steel

    SciTech Connect

    Yan Haitao [Key Laboratory for High Temperature Materials and Tests of Ministry of Education, Shanghai Jiao Tong University, Shanghai 200030 (China); Shanghai Baosteel Research Institute, Shanghai 200431 (China)], E-mail: yanhaitao@sjtu.edu.cn; Bi Hongyun; Li Xin [Shanghai Baosteel Research Institute, Shanghai 200431 (China); Xu Zhou [Key Laboratory for High Temperature Materials and Tests of Ministry of Education, Shanghai Jiao Tong University, Shanghai 200030 (China)

    2008-12-15

    The microstructure, texture and grain boundary character distribution of Nb + Ti stabilized ferritic stainless steel were analyzed using scanning electron microscopy, transmission electron microscopy and X-ray diffraction. The addition of alloying elements such as Ti and Nb to ferritic stainless steel causes the formation of TiN, NbC and Fe{sub 2}Nb. The textures of cold rolled samples were dominated by the {alpha}-fiber, while the textures of annealed samples exhibit a very strong {gamma}-fiber. The changes in texture are closely related to the grain boundary characteristics.

  11. Effect of microstructure on pitting and corrosion fatigue of 17-4 PH turbine blade steel in chloride environments

    SciTech Connect

    Syrett, B.C.; Viswanathan, R.

    1982-02-01

    Depending on its heat treatment, 17-4 PH stainless steel may contain significant levels of reformed austenite and untempered martensite in a matrix of tempered martensite. Shot peening can cause changes in the microstructure of the surface layers by transforming the austenite to untempered martensite. The effect of these microstructural varations on the resistance of 17-4 PH stainless steel to pitting and corrosion fatigue has been determined in simulated steam turbine environments. The results of two electrochemical tests (large amplitude cyclic voltammetry and the pit propagation rate (PPR) test) indicate that tempering temperature and shot peening have only minor effects on resistance to pit initiation and propagation in any one of three aqueous chloride environments. However, the susceptibility of this stainless steel to corrosion fatigue in one of these environments (6 wt % FeCl/sub 3/) was reduced by increasing the tempering temperature from 538/sup 0/C (1000/sup 0/F) to 649/sup 0/C (1200/sup 0/F).

  12. Environment-Assisted Cracking in Custom 465 Stainless Steel

    Microsoft Academic Search

    E. U. Lee; R. Goswami; M. Jones; A. K. Vasudevan

    2011-01-01

    The influence of cold work and aging on the environment-assisted cracking (EAC) behavior and mechanical properties of Custom 465 stainless steel (SS) was studied. Four sets of specimens were made and tested. All specimens were initially solution annealed, rapidly cooled, and refrigerated (SAR condition). The first specimen set was steel in the SAR condition. The second specimen set was aged

  13. Manufacturing Process Advancements for Flexible CIGS PV on Stainless Foil

    Microsoft Academic Search

    B. S. Joshi; R. J. Kee; G. J. Kleen; R. B. Huntington; E. Sheehan

    Substantial improvements in production cell efficiency and yield have been achieved for roll-to-roll CIGS PV on stainless foil at GSE. Large area cells (68.8 cm 2 ) have advanced to >13% efficiency, with a maximum frequency of distribution near 11% in some production lots (Figure 1). Yield has increased from 20% to 90% (Figure 1) through process, equipment and procedural

  14. Battery and fuel cell electrodes containing stainless steel charging additive

    DOEpatents

    Zuckerbrod, David (Pittsburgh, PA); Gibney, Ann (Monroeville, PA)

    1984-01-01

    An electrode for use in electrochemical energy cells is made, comprising a hydrophilic layer and a hydrophobic layer, where the hydrophilic layer comprises a hydrophilic composite which includes: (i) carbon particles; (ii) stainless steel particles; (iii) a nonwetting agent; and (iv) a catalyst, where at least one current collector contacts said composite.

  15. Bactericidal behavior of Cu-containing stainless steel surfaces

    NASA Astrophysics Data System (ADS)

    Zhang, Xiangyu; Huang, Xiaobo; Ma, Yong; Lin, Naiming; Fan, Ailan; Tang, Bin

    2012-10-01

    Stainless steels are one of the most common materials used in health care environments. However, the lack of antibacterial advantage has limited their use in practical application. In this paper, antibacterial stainless steel surfaces with different Cu contents have been prepared by plasma surface alloying technology (PSAT). The steel surface with Cu content 90 wt.% (Cu-SS) exhibits strong bactericidal activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) within 3 h. Although the Cu-containing surface with Cu content 2.5 wt.% (CuNi-SS) can also kill all tested bacteria, this process needs 12 h. SEM observation of the bacterial morphology and an agarose gel electrophoresis were performed to study the antibacterial mechanism of Cu-containing stainless steel surfaces against E. coli. The results indicated that Cu ions are released when the Cu-containing surfaces are in contact with bacterial and disrupt the cell membranes, killing the bacteria. The toxicity of Cu-alloyed surfaces does not cause damage to the bacterial DNA. These results provide a scientific explanation for the antimicrobial applications of Cu-containing stainless steel. The surfaces with different antibacterial abilities could be used as hygienic surfaces in healthcare-associated settings according to the diverse requirement of bactericidal activities.

  16. Preparation of super-hydrophobic surface on stainless steel

    Microsoft Academic Search

    Li Juan Chen; Miao Chen; Hui Di Zhou; Jian Min Chen

    2008-01-01

    To mimic the lotus leaf structure, binary microstructures at both micro- and nano-scale were constructed on the stainless steel surface by the eletroless plating. Super-hydrophobicity was achieved with a water contact angle of 150° and the sliding angle of 4° by modifying the textured surface by means of HFTHTMS ((heptadecafluoro-1,1,2,2-tetrahydrodecyl) trimethoxysilane).

  17. Effects of gases on laser cutting of stainless steels

    SciTech Connect

    Gabzdyl, J.T. [BOC Gases, Guildford (United Kingdom)

    1996-12-31

    This paper highlights the differences between the use of oxygen and nitrogen as the assist gas for cutting stainless steels in terms of cut quality, productivity and fume generation. Results show that gas purity has a significant effect on cutting speed and edge quality. The main gas supply options and their relative merits are also discussed.

  18. New equation of state for stainless steel 347

    SciTech Connect

    Boettger, J.C.

    1993-12-01

    A new SESAME equation of state (EOS) for stainless steel 347 has been generated using the computer program GRIZZLY, and has been added to the SESAME EOS library as material number 4271. This new EOS is superior to its predecesser (material number 4270) in several respects.

  19. Impact Tensile Testing of Stainless Steels at Various Temperatures

    Microsoft Academic Search

    D. K. Morton

    2008-01-01

    Stainless steels are used for the construction of numerous spent nuclear fuel or radioactive material containers that may be subjected to high strains and moderate strain rates during accidental drop events. Mechanical characteristics of these base materials and their welds under dynamic loads in the strain rate range of concern (1 to 300 per second) are not well documented. However,

  20. Impact Testing of Stainless Steel Material at Cold Temperatures

    Microsoft Academic Search

    Spencer D. Snow; D. Keith Morton; Robert K. Blandford

    2008-01-01

    Stainless steels are used for the construction of numerous spent nuclear fuel or radioactive material containers that may be subjected to high strains and moderate strain rates during accidental drop events. Mechanical characteristics of these base materials and their welds under dynamic loads in the strain rate range of concern are not well documented. However, a previous paper [1] reported

  1. Corrosion resistance of friction stir welded 304 stainless steel

    Microsoft Academic Search

    Seung Hwan C. Park; Yutaka S. Sato; Hiroyuki Kokawa; Kazutaka Okamoto; Satoshi Hirano; Masahisa Inagaki

    2004-01-01

    Corrosion properties were evaluated in a friction stir welded 304 stainless steel. The degree of the sensitization was small in the heat affected zone, but the advancing side of the stir zone was corroded significantly because of the formation of the sigma phase.

  2. Rapid solidification of a droplet-processed stainless steel

    Microsoft Academic Search

    Thomas F. Kelly; Morris Cohen; John B. Vander Sande

    1984-01-01

    Individual powder particles of a droplet-processed and rapidly solidified 303 stainless steel are characterized in terms of microstructure and composition variations within the solidification structure using scanning transmission electron microscopy (STEM). Fcc is found to be the crystallization phase in powder particles larger than about 70 micron diameter, and bcc is the crystallization phase in the smaller powder particles. An

  3. Damage analysis during hot deformation of a resulfurised stainless steel

    Microsoft Academic Search

    H. Tinet; H. Klöcker; J. Le Coze

    2004-01-01

    Ductile damage evolution and fracture of a resulfurised stainless steel (AISI 303) were analysed by high temperature tension tests. Void nucleation, growth and coalescence were investigated. The existence of two distinct void coalescence mechanisms has been demonstrated. High temperature damage models assume the existence of a critical value of the void volume fraction at the onset of void coalescence. In

  4. Materials data handbook: Stainless steel alloy A-286

    NASA Technical Reports Server (NTRS)

    Muraca, R. F.; Whittick, J. S.

    1972-01-01

    A summary of the materials property information for stainless steel alloy A-286 is presented. The scope of the information includes physical and mechanical properties at cryogenic, ambient, and elevated temperatures. Information on material procurement, metallurgy of the alloy, corrosion, environmental effects, fabrication, and bonding is developed.

  5. Microstructural Development during Solidification of Stainless Steel Alloys

    E-print Network

    Eagar, Thomas W.

    ) Microstructural Development during Solidification of Stainless Steel Alloys J.W. ELMER, S alloys are related to the solidification conditions and the specific alloy composition and the chemical composition of the alloy both influence (I) the primary mode of solidification, (2) solute

  6. Evaluation of biological monitoring among stainless steel welders

    Microsoft Academic Search

    E. Rahkonen; Marja-Leena Junttila; Pirkko Liisa Kalliomiiki; Maritta Olkinouoral; M. Koponen; K. Kalliomäki

    1983-01-01

    Ten manual metal arc (MMA) high alloy stainless steel (SS) welders were studied during one week and the concentrations of chromium (Cr) and nickel (Ni) were determined in their urine and blood. Stationary and personal air samples were collected from the immediate work environment; they covered the entire work period. Spot urine samples were collected during the follow-up period. Whole

  7. Modelling the Material Behaviour of Metastable Stainless Steels

    Microsoft Academic Search

    K. Datta; H. J. M. Geijselaers; J. Post; J. Beyer; J. Huètink; Abel D. Santos

    2007-01-01

    Metastable austenitic stainless steels are designed to be thermodynamically unstable such that deformation even at room temperatures can bring about a change, in the phase of face centred cubic austenite to either hexagonal close packed martensite and\\/or to body centred cubic martensite. This solid state phase change is a function of the strain path, strain, strain rate and temperature. A

  8. Corrosion behavior of the stainless steel composing dental magnetic attachments

    Microsoft Academic Search

    Yukyo Takada; Keisuke Nakamura; Kohei Kimura; Osamu Okuno

    2005-01-01

    Corrosion behavior of stainless steel used for dental magnetic attachment was examined in contact with the other dental metals. Coupling of a gold alloy for metal-ceramics and type 316L had a risk of corrosion damage in a large difference of their surface areas.

  9. Chemical Speciation of Heavy Metals in Stainless Steel Plant Dust

    Microsoft Academic Search

    Guojun Ma; Wei Fan; Hui Tang; Wei Wang; Weihou Su

    2010-01-01

    The leaching tests and the sequential extraction procedure of heavy metals in the stainless steel plant dusts were studied. The results show that the total Cr and Cr (VI) content in argon oxygen decarburization converter dust (AODD), and the concentrations of Cd and Zn in electric arc furnace dust (EAFD) exceed the national standards. Lead is the most extractable element

  10. 6. DETAIL OF STAINLESS STEEL VISCERA CHUTE IN SOUTHEAST CORNER ...

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

    6. DETAIL OF STAINLESS STEEL VISCERA CHUTE IN SOUTHEAST CORNER OF LEVEL4; ENTRAILS WERE DROPPED INTO CHUTE, THEN PASSED THROUGH THE FLOOR TO THE GUT SHANTY ON LEVEL 3 TO BE SORTED AND CLEANED - Rath Packing Company, Hog Dressing Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

  11. Mechanical properties of four RSP stainless steel alloys

    SciTech Connect

    Korth, G.E.

    1996-12-01

    Four austenitic stainless steel alloys were processed by consolidating rapidly solidified gas atomized power using hot extrusion. These materials were characterized by measuring grain growth, hardness, tensile properties from 24 to 800{degrees}C, and creep-rupture at 600{degrees}C.

  12. Characterization of austenitic stainless steel welds for ultrasonic NDT

    Microsoft Academic Search

    B. Chassignole; D. Villard; M. Dubuget; J.-C. Baboux; R. El Guerjouma

    2000-01-01

    Electricité de France has started a study in collaboration with the Metallurgical and Materials Physics Study Group (GEMPPM) of INSA-Lyon, to evaluate the effect of metallurgical structures of austenitic stainless steel welds on wave propagation for application to ultrasonic nondestructive testing. Experimentally, the anisotropic and heterogeneous characteristics of austenitic welds together with a coarse-grained structure (elongated and oriented grains) lead

  13. No genotoxicity of a new nickel-free stainless steel.

    PubMed

    Montanaro, L; Cervellati, M; Campoccia, D; Prati, C; Breschi, L; Arciola, C R

    2005-01-01

    Stainless steel is a metallic alloy largely employed in orthopedics, maxillofacial surgery and orthodontic therapy. However, the presence in its composition of a high quantity of nickel, an agent known to trigger toxic, allergic and cancerogenous responses in humans, is cause of some concern. In this study, we have investigated the in vitro mutagenicity and genotoxicity of a new nickel-free stainless steel, namely P558, in comparison to the conventional stainless steel AISI 316L. The cytogenetic effects were evaluated by studying the frequency of Sister Chromatid Exchanges (SCE) and chromosomal aberrations. Ames test was performed to detect the mutagenic activity. Both P558 and AISI 316L did not cause any significant increase in the average number of SCE and in chromosomal aberrations, either with or without metabolic activation. Furthermore, the Ames test showed that the extracts of both P558 and of AISI 316L are not mutagenic. Overall, these findings prove that P558 is devoid of genotoxicity and mutagenicity. The present results, together with other previous interesting observations that P558 promotes osseointegration, suggest that this new nickel-free stainless steel can represent a better alternative to other conventional steel alloys. PMID:15742311

  14. DEVELOPMENTS IN PERMANENT STAINLESS STEEL CATHODES WITHIN THE COPPER INDUSTRY

    Microsoft Academic Search

    K. L. Eastwood; G. W. Whebell

    The ISA PROCESS™ cathode plate is characterised by its copper coated suspension bar, coupled with a blade employing austenitic stainless steel alloy 316L. The blade material has become the mainstay of the technology and has been closely copied by competing cathode designs. Improvement to the cathode plate design remains a key area for research, and ongoing developments by Xstrata Technology's

  15. Rutherford backscattering analysis of gallium implanted 316 stainless steel

    E-print Network

    Ortensi, Javier

    2000-01-01

    Ion implantation of Ga ions into 316 stainless steel was performed at fluences ranging from 8x10¹? to 10¹? ions/cm². The depth profile of Ga in the steel was analyzed via Rutherford Backscattering and ToFSIMS. The surface effects were...

  16. High temperature corrosion behavior of siliconized 310 stainless steel

    Microsoft Academic Search

    Hung-Wen Hsu; Wen-Ta Tsai

    2000-01-01

    Surface alloying of Si into AISI 310 austenitic stainless steel (SS) to increase its high temperature corrosion resistance was attempted by employing pack cementation process. High temperature corrosion resistances of AISI 310 SS with or without siliconization treatment were evaluated in air and in CO\\/CO2 gas mixtures at 700, 750 and 800°C. The experimental results showed that the weight losses

  17. New equation of state for stainless steel 347

    Microsoft Academic Search

    Boettger

    1993-01-01

    A new SESAME equation of state (EOS) for stainless steel 347 has been generated using the computer program GRIZZLY, and has been added to the SESAME EOS library as material number 4271. This new EOS is superior to its predecesser (material number 4270) in several respects.

  18. Practical handbook of stainless steels and nickel alloys

    Microsoft Academic Search

    Lamb

    1999-01-01

    This new handbook is an up-to-date technical guide to the grades, properties, fabrication characteristics, and applications of stainless steels and nickel alloys. The individual chapters were written by industry experts and focus on the key properties and alloy characteristics important in material selection and specification as well as the practical factors that influence the development and application of these materials.

  19. Neural network model of creep strength of austenitic stainless steels

    E-print Network

    Cambridge, University of

    Neural network model of creep strength of austenitic stainless steels T. Sourmail, H. K. D. H, and solution treatment temperature. The method involved a neural network analysis of a vast and general, and stress. Neural networks represent a more general regression method, which ameliorates most

  20. Surface nanocrystallization of stainless steel for reduced biofilm adherence

    Microsoft Academic Search

    Bin Yu; Elisabeth M. Davis; Robert S. Hodges; Randall T. Irvin; D. Y. Li

    2008-01-01

    Stainless steel is one of the most common metallic biomedical materials. For medical applications, its resistance to the adherence of biofilms is of importance to the elimination or minimization of bacterial infections. In this study, we demonstrate the effectiveness of a process combining surface nanocrystallization and thermal oxidation (or a recovery heat treatment in air) for reducing the biofilm's adherence

  1. Surface nanocrystallization of stainless steel for reduced biofilm adherence

    Microsoft Academic Search

    Bin Yu; Elisabeth M Davis; Robert S Hodges; Randall T Irvin; D Y Li

    2008-01-01

    Stainless steel is one of the most common metallic biomedical materials. For medical applications, its resistance to the adherence of biofilms is of importance to the elimination or minimization of bacterial infections. In this study, we demonstrate the effectiveness of a process combining surface nanocrystallization and thermal oxidation (or a recovery heat treatment in air) for reducing the biofilm’s adherence

  2. Stainless steel 301 and Inconel 718 hydrogen embrittlement

    NASA Technical Reports Server (NTRS)

    Allgeier, R. K.; Forman, R.

    1970-01-01

    Conditions and results of tensile tests of 26 Inconel 718 and four cryoformed stainless steel specimens are presented. Conclusions determine maximum safe hydrogen operating pressure for cryogenic pressure vessels and provide definitive information concerning flaw growth characteristics under the most severe temperature and pressure conditions

  3. Fatigue crack propagation behavior of stainless steel welds

    Microsoft Academic Search

    Chad S. Kusko

    2002-01-01

    The fatigue crack propagation behavior of austenitic and duplex stainless steel base and weld metals has been investigated using various fatigue crack growth test procedures, ferrite measurement techniques, light optical microscopy, stereomicroscopy, scanning electron microscopy, and optical profilometry. The compliance offset method has been incorporated to measure crack closure during testing in order to determine a stress ratio at which

  4. WELDING PROPERTIES OF CHROMIUM-NICKEL-MOLYBDENUM HARDENABLE STAINLESS STEELS

    Microsoft Academic Search

    Kaltenhauser

    1959-01-01

    BS>Semiaustenitic hardenable stainless steels types AM-350 and AM-355 ; were found to have excellent weldability by the same techniques and processes ; that are used for austenitic stainiess steels. By appropriate low-temperature ; postweld heat treatments, the weld and base metals may be transformed to a high-; strength tempered martensitic structure. Both alloys have welded and hardened ; strengths equal

  5. Ferritic, martensitic, and precipitation hardening stainless steel laser weldings

    Microsoft Academic Search

    Giuseppe Daurelio; Antonio D. Ludovico; Christos N. Panagopoulos; Corrado Tundo

    1998-01-01

    Even if many steels and alloys have been welded on the last years, nowadays there are some other stainless steel alloys that need a further comprehension when they have to be welded. Typically these alloys are martensitic and precipitation hardening ones that still present some problems to be weld, i.e. hot cracks, fragile beads, an excessive grain size and other

  6. Evaluation of Hot Cracking in Austenitic Stainless Steel Welds

    Microsoft Academic Search

    V. Shankar; S. L. Mannan

    1992-01-01

    A number of criteria such as crack lengths, brittleness temperature range (BTR), critical strain and critical strain rate for initiation of cracking are used for evaluation of solidification cracking susceptibility of austenitic stainless steel welds. The strain response of the material during welding is commonly described (1) as a temperature range using temperature-strain co-ordinates, called the brittleness temperature range. However,

  7. TRENDS IN FORMING AND WELDING OF STAINLESS STEELS

    Microsoft Academic Search

    H. Hänninen; J. Romu

    Various new forming techniques (hydroforming, superplastic forming and hot metal gas forming) have become an alternative to various stamping processes. The technologies are still rather new and there is not yet enough information available to assist the product design and manufacturing. Welding of stainless steels is still often based on the conventional welding techniques, but recently high energy density laser

  8. Weld solidification cracking in 304 to 204L stainless steel

    Microsoft Academic Search

    Patrick W Hochanadel; Thomas J Lienert; Jesse N Martinez; Matthew Q Johnson

    2010-01-01

    A series of annulus welds were made between 304 and 304L stainless steel coaxial tubes using both pulsed laser beam welding (LBW) and pulsed gas tungsten arc welding (GTAW). In this application, a change in process from pulsed LBW to pulsed gas tungsten arc welding was proposed to limit the possibility of weld solidification cracking since weldability diagrams developed for

  9. Weld solidification cracking in 304 to 304L stainless steel

    Microsoft Academic Search

    Patrick W Hochanadel; Thomas J Lienert; Jesse N Martinez; Raymond J Martinez; Matthew Q Johnson

    2010-01-01

    A series of annulus welds were made between 304 and 304L stainless steel coaxial tubes using both pulsed laser beam welding (LBW) and pulsed gas tungsten arc welding (GTAW). In this application, a change in process from pulsed LBW to pulsed gas tungsten arc welding was proposed to limit the possibility of weld solidification cracking since weldability diagrams developed for

  10. 2012 ACCOMPLISHMENTS - TRITIUM AGING STUDIES ON STAINLESS STEELS

    SciTech Connect

    Morgan, M.

    2013-01-31

    This report summarizes the research and development accomplishments during FY12 for the tritium effects on materials program. The tritium effects on materials program is designed to measure the long-term effects of tritium and its radioactive decay product, helium-3, on the structural properties of forged stainless steels which are used as the materials of construction for tritium reservoirs. The FY12 R&D accomplishments include: (1) Fabricated and Thermally-Charged 150 Forged Stainless Steel Samples with Tritium for Future Aging Studies; (2) Developed an Experimental Plan for Measuring Cracking Thresholds of Tritium-Charged-and-Aged Steels in High Pressure Hydrogen Gas; (3) Calculated Sample Tritium Contents For Laboratory Inventory Requirements and Environmental Release Estimates; (4) Published report on “Cracking Thresholds and Fracture Toughness Properties of Tritium-Charged-and-Aged Stainless Steels”; and, (5) Published report on “The Effects of Hydrogen, Tritium, and Heat Treatment on the Deformation and Fracture Toughness Properties of Stainless Steels”. These accomplishments are highlighted here and references given to additional reports for more detailed information.

  11. Reactor Material Program Fracture Toughness of Type 304 Stainless Steel

    SciTech Connect

    Awadalla, N.G.

    2001-03-28

    This report describes the experimental procedure for Type 304 Stainless Steel fracture toughness measurements and the application of results. Typical toughness values are given based on the completed test program for the Reactor Materials Program (RMP). Test specimen size effects and limitations of the applicability in the fracture mechanics methodology are outlined as well as a brief discussion on irradiation effects.

  12. Laser-assisted microscale deformation of stainless steels and ceramics

    E-print Network

    Xu, Xianfan

    the storage capacity in a hard drive is to reduce the distance between the disk surface and the disk head head and the hard disk surface. Experiments are conducted to study the bending behavior of stainless. For computer hard disks with capacities greater than 10 Gbytes/in.2 , the distance between the disk head

  13. Precipitation sequence in niobium-alloyed ferritic stainless steel

    Microsoft Academic Search

    Nobuhiro Fujita; H. K. D. H. Bhadeshia; Masao Kikuchi

    2004-01-01

    Niobium is an important alloying element in the design of heat-resistant ferritic stainless steels for automotive exhaust systems. When in solid solution, it improves both the high temperature strength and the resistance to thermal fatigue. However, it also forms several kinds of precipitates during service. These reactions have been modelled, taking into account the multicomponent nature of the diffusion process

  14. 73. View of line of stainless steel coolant storage tanks ...

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

    73. View of line of stainless steel coolant storage tanks for bi-sodium sulfate/water coolant solution at first floor of transmitter building no. 102. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

  15. Brazing of Stainless Steel to Various Aluminum Alloys in Air

    NASA Astrophysics Data System (ADS)

    Liu, Shuying; Suzumura, Akio; Ikeshoji, Toshi-Taka; Yamazaki, Takahisa

    Brazing of a stainless steel to various aluminum alloys was carried out using an Al-Si filler metal and a fluoride-active flux in air. The brazeability was remarkably different by the aluminum alloys and the brazing conditions. It was considered that the differences were originated with the compositions of base metals and the filler metal, the solidus temperature and the partially melting behavior of the aluminum alloys, and the behavior of the surface oxide film layers of both base metals. On the other hand, the obstruction of brazeability was identified as the rapid reaction between the aluminum alloys and the brazing filler metal, which makes the molten brazing filler metal disappear at the joining interface before the wetting occurs to the stainless steel. Taking this phenomena into consideration, it was attempted to make previous wetting of the brazing filler to the stainless steel before brazing to the aluminum alloys. This method provided the successful brazed joints for the most combinations of the stainless steel and the aluminum alloys.

  16. Properties of super stainless steels for orthodontic applications.

    PubMed

    Oh, Keun-Taek; Kim, Young-Sik; Park, Yong-Soo; Kim, Kyoung-Nam

    2004-05-15

    Orthodontic stainless-steel appliances are considered to be corrosion resistant, but localized corrosion can occur in the oral cavity. This study was undertaken to evaluate the properties of super stainless steels in orthodontic applications. Accordingly, the metallurgical properties, mechanical properties, corrosion resistance, amount of the released nickel, cytotoxicity, and characteristics of the passive film were investigated. Corrosion resistances of the specimens were high and in the following order: super austenitic stainless steel (SR-50A) > super ferritic stainless steel (SFSS) = super duplex stainless steel (SR-6DX) > 316L SS > super martensitic stainless steel (SR-3Mo) in artificial saliva, 37 degrees C. At 500 mV (SCE), current densities of SR-50A, SFSS, SR-6DX, 316L SS, and SR-3Mo were 5.96 microA/cm(2), 20.3 microA/cm(2), 31.9 microA/cm(2), 805 microA/cm(2), and 5.36 mA/cm(2), respectively. Open circuit potentials of SR-50A, 316L SS, SR-6DX, SR-3Mo, and SFSS were - 0.2, - 0.22, - 0.24, - 0.43, and - 0.46 V (SCE), respectively. SR-50A, SFSS, and SR-6DX released below 3 ng/ml nickel for 8 weeks, and increased a little with immersion time, and 316L SS released about 3.5 ng/ml nickel, but SR-3Mo released a large amount of nickel, which increased with immersion time. The study demonstrated that SR-50A, SR-6DX, and SFSS have high corrosion resistance and mild or no cytotoxicity, due to the passive film enhanced by synergistic effect of Mo + N or by high addition effect of Cr + W. All super stainless steels showed very low cytotoxicity regardless of their nickel contents, although SR-3Mo was found to be relatively cytotoxic. From these studies, these steels are considered suitable for orthodontic applications. PMID:15116408

  17. Electrochemical techniques for the analysis of corrosion in stainless steel components. 303 stainless steel in contact with TATB

    Microsoft Academic Search

    Firsich

    1985-01-01

    Electrochemical techniques can be used to predict the corrosion characteristics of a metal in a specific environment. The basic electrochemical principles, experimental techniques, and a detailed study of their use in characterizing the corrosion behavior of a particular 303 stainless steel are presented. This metal is the material of construction in a weapons component that comes in contact with 416

  18. CORROSION STUDY FOR THE EFFLUENT TREATMENT FACILITY (ETF) CHROME (VI) REDUCTANT SOLUTION USING 304 & 316L STAINLESS STEEL

    SciTech Connect

    DUNCAN, J.B.

    2007-06-27

    The Effluent Treatment Facility has developed a method to regenerate spent resin from the groundwater pump and treat intercepting chrome(VI) plumes (RPP-RPT-32207, Laboratory Study on Regeneration of Spent DOWEX 21K 16-20 Mesh Ion Exchange Resin). Subsequent laboratory studies have shown that the chrome(VI) may be reduced to chrome(III) by titrating with sodium metabisulfite to an oxidation reduction potential (ORP) of +280 mV at a pH of 2. This test plan describes the use of cyclic potentiodynamic polarization and linear polarization techniques to ascertain the electrochemical corrosion and pitting propensity of the 304 and 316L stainless steel in the acidified reducing the solution that will be contained in either the secondary waste receiver tank or concentrate tank.

  19. Magnetic fields from electric toothbrushes promote corrosion in orthodontic stainless steel appliances but not in titanium appliances.

    PubMed

    Kameda, Takashi; Ohkuma, Kazuo; Oda, Hirotake; Sano, Natsuki; Batbayar, Nomintsetseg; Terashima, Yukari; Sato, Soh; Terada, Kazuto

    2013-11-30

    Electric toothbrushes are widely used, and their electric motors have been reported to produce low-frequency electromagnetic fields that induced electric currents in metallic objects worn by the users. In this study, we showed that electric toothbrushes generated low-frequency magnetic fields (MFs) and induced electric currents in orthodontic appliances in artificial saliva (AS), which accelerated corrosion in stainless steel (SUS) appliances, but not in titanium (Ti) appliances; the corrosion was evaluated by using an inductively coupled plasma-optical emission spectrometer and a three-dimensional laser confocal microscope. The pH of AS used for appliance immersion did not change during or after MF exposure. These results suggested that MF-induced currents from electric toothbrushes could erode SUS appliances, but not Ti appliances, because of their high corrosion potentials. Further studies are required to clarify the mechanisms of metallic corrosion by induced currents in dental fields, which may trigger metal allergies in patients. PMID:24240898

  20. The dimensional stability analysis of seventeen stepped specimens of 18Ni 200 grade, PH13-8Mo and A-286

    NASA Technical Reports Server (NTRS)

    Wigley, D. A.

    1983-01-01

    This report documents the results of a dimensional stability analysis of seventeen stepped specimens that were used in the evaluation of factors influencing warpage in metallic alloys being used for cryogenic wind tunnel models. Specimens used in the analysis were manufactured from 18Ni 200 Grade Maaraging steel, PH13-8Mo, and A-286 stainless steel. Quantitative data are provided on the behavior of the specimens due to the effects of both machining and cryogenic cycling effects.

  1. Wetting Properties of Liquid Lithium on Stainless Steel and Enhanced Stainless Steel Surfaces

    NASA Astrophysics Data System (ADS)

    Fiflis, P.; Xu, W.; Raman, P.; Andruczyk, D.; Ruzic, D. N.; Curreli, D.

    2012-10-01

    Research into lithium as a first wall material has proven its ability to effectively getter impurities and reduce recycling of hydrogen ions at the wall. Current schemes for introducing lithium into a fusion device consist of lithium evaporators, however, as these devices evolve from pulsed to steady state, new methods will need to be employed such as the LIMIT concept of UIUC, or thin flowing film lithium walls. Critical to their implementation is understanding the interactions of liquid lithium with various surfaces. One such interaction is the wetting of materials by lithium, which may be characterized by the contact angle between the lithium and the surface. Experiments have been performed at UIUC into the contact angle of liquid lithium with a given surface, as well as methods to increase it. To reduce the oxidation rate of the droplets, the experiments were performed in vacuum, using a lithium injector to deposit drops on each surface. Among the materials investigated are stainless steel, both untreated and coated with a diamond like carbon (DLC) layer, molybdenum, and boronized molybdenum. The contact angle and its dependence on temperature is measured.

  2. Foamability of stainless steelmaking slags in an EAF

    NASA Astrophysics Data System (ADS)

    Kerr, James John

    Foaming in electric furnace steelmaking is desirable to allow for a longer arc and subsequently higher power operation in order to reduce the tap to tap time and consequently increase productivity. Stainless steelmaking slags do not foam as well as carbon steelmaking slags. To produce foam, the foamability or foam index of a slag and the gas generation rate must be adequate. The possible causes for the poor foamability of stainless steelmaking slags were examined in this research. Specifically the foam index of a simulated stainless steelmaking slag containing chrome oxide was measured and the rate at which carbon reacts with Cr2O3, CrO, and FeO was also measured. The experimental results show that the foam index of stainless steelmaking slags is comparable to carbon steelmaking slags provided that the amount of solid chrome oxide particles or complexes is not excessive. This indicates the low foamability is not due to a poor foam index. Gas is normally generated by cycling carbon into the slag, which produces CO by reducing oxides in the slag. The experimental results demonstrate that the reaction rate of carbon with CrO dissolved in the slag and hence the generation of CO is significantly slower than for the reaction rate of carbon with FeO dissolved in slags. Therefore, the lack of FeO or other reducible oxides in stainless steelmaking slags is a primary reason for the poor foamability. Experimental results indicate that limestone, nickel oxide, calcium nitrate, and waste oxide briquettes generate gas at sufficient rates to induce foaming when added to the stainless steelmaking slag. Heat transfer most likely controls the rate of CO2 generated by limestone and NiO reduction is controlled by mass transfer of NiO to the carbon in the slag. WOBs generate gas very rapidly due to intimate mixing of the carbon and iron oxides at unit activity. Calcium nitrate generates gas by dissociation and heat transfer likely controls the dissociation rate. Simple models are constructed that should estimate the amount of additions that are needed to achieve a specified foam height. The additions modeled include limestone, NiO, and FeO. In addition, a practice to generate foam from CrO in the slag by increasing the CrO activity coefficient is considered.

  3. Accelerated corrosion of stainless steel in thiocyanate-containing solutions

    SciTech Connect

    Pistorius, P Chris; Li, Wen

    2012-09-19

    It is known that reduced sulfur compounds (such as thiocyanate and thiosulfate) can accelerate active corrosion of austenitic stainless steel in acid solutions, but before we started this project the mechanism of acceleration was largely unclear. This work combined electrochemical measurements and analysis using scanning electron microscopy (SEM) and X-ray photo-electron spectroscopy (XPS), which provided a comprehensive understanding of the catalytic effect of reduced sulfur species on the active corrosion of stainless steel. Both the behavior of the pure elements and the steel were studied and the work focused on the interaction between the pure elements of the steel, which is the least understood area. Upon completion of this work, several aspects are now much clearer. The main results from this work can be summarized as follows: The presence of low concentrations (around 0.1 mM) of thiocyanate or tetrathionate in dilute sulfuric acid greatly accelerates the anodic dissolution of chromium and nickel, but has an even stronger effect on stainless steels (iron-chromium-nickel alloys). Electrochemical measurements and surface analyses are in agreement with the suggestion that accelerated dissolution really results from suppressed passivation. Even well below the passivation potential, the electrochemical signature of passivation is evident in the electrode impedance; the electrode impedance shows clearly that this pre-passivation is suppressed in the presence of thiocyanate. For the stainless steels, remarkable changes in the morphology of the corroded metal surface and in the surface concentration of chromium support the suggestion that pre-passivation of stainless steels is suppressed because dissolution of chromium is accelerated. Surface analysis confirmed that adsorbed sulfur / sulfide forms on the metal surfaces upon exposure to solutions containing thiocyanate or thiosulfate. For pure nickel, and steels containing nickel (and residual copper), bulk sulfide (visible as a black corrosion product) forms during anodic dissolution. The sulfide is electronically conductive, and gives an increase of several orders of magnitude in the electrode capacitance; the sulfide also causes anodic activation to persist after the pure metals and steels were removed from the thiocyanate-containing electrolyte and transferred to a thiocyanate-free electrolyte. The main practical implications of this work are that low concentrations of reduced sulfur compounds strongly affect anodic dissolution of stainless steels, and that selecting steels with elevated concentrations of chromium, nickel or molybdenum would serve to limit the anodic dissolution rate in the presence of reduced sulfur compounds.

  4. Hydrogen uptake and cracking in 22% Cr duplex stainless steel under galvanic coupling conditions

    SciTech Connect

    Griffiths, A.J.; Turnbull, A. [National Physical Lab., Teddington (United Kingdom). Centre for Materials Measurement and Technology

    1997-09-01

    Tests were conducted to evaluate the performance of 22% Cr duplex stainless steel (DSS) coupled to carbon steel (CS) in acid brine environments at 80 C with and without hydrogen sulfide (H{sub 2}S). Measurement of coupled potentials and currents were made in parallel with a detailed evaluation of the effects of H{sub 2}S, pH, and coupling current on hydrogen uptake. Hydrogen contents generated under coupling conditions were large, on the order of 100 ppm (by wt) total hydrogen. At low charging currents, hydrogen uptake was independent of pH and H{sub 2}S and proportional to the square root of the charging current density (i{sup 1/2}). As the charging current increased, a critical value was reached above which hydrogen uptake was independent of charging current in H{sub 2}S-free solution. In H{sub 2}S-saturated solution, hydrogen uptake remained proportional to i{sup 1/2}. The measurements of hydrogen uptake provide a reference framework for identifying critical parameters for stress corrosion testing and interpretation of results. Preliminary stress corrosion tests were conducted using the slow strain rate testing (SSRT) technique. The threshold total hydrogen content for environment-assisted cracking was between 100 ppm and 250 ppm (bh wt) for the alloy tested. No reduction in strain-to-failure relative to oil was observed in H{sub 2}S-free environments. Results from permeation and cracking tests suggested cracking will occur only in H{sub 2}S environments at coupling currents > 100 {micro}A/cm{sup 2}. Nevertheless, currents of this magnitude may be realized in practice.

  5. Chloride-induced stress corrosion cracking of powder metallurgy duplex stainless steels

    SciTech Connect

    Laitinen, A.; Haenninen, H. [Helsinki Univ. of Technology, Espoo (Finland). Lab. of Engineering Materials

    1996-04-01

    The chloride-induced stress corrosion cracking (SCC) resistance of nitrogen-alloyed, powder metallurgically (P/M) produced and hot isostatically pressed (HIP) duplex stainless steels (DSS) was investigated and compared to the SCC resistance of two commercial wrought (forged) DSS. Constant-strain (deflection) SCC tests with four-point, loaded-bend specimens were performed in aerated 50 wt% calcium chloride solution at 100 C with pH = 6.5 to 7.0. The pitting corrosion resistance index value (PREN) was not a suitable parameter to predict SCC resistance of the investigated DSS. Instead of pitting corrosion, selective corrosion of the austenite or ferrite phases seemed to determine the SCC resistance of each material. Selective corrosion was not the primary cause for failure, but it assisted the initiation and growth of stress corrosion cracks. Selective corrosion was noticed in all of the investigated DSS. The corroding phase, austenite or ferrite, was dependent on the material. High copper content in the specific material slightly lowered the stress limit at which stress corrosion cracks started to grow in the used test solution. The SCC resistance of P/M-HIP DSS was as good as the SCC resistance of forged DSS. The banded microstructure of forged DSS led to a directional selective corrosion attack. The corrosion grooves were ideal sites for initiation of SCC. Because of this phenomenon, the homogeneous microstructure of P/M-HIP DSS showed clear advantages over the banded microstructure of forged DSS.

  6. The Biological Safety of Stainless Steel Needles Used in Warm-needling

    PubMed Central

    Lee, Seunghun; Yi, Seung-Ho; Son, Yang-Sun; Choi, Sung-min; Kim, Young-Kon

    2010-01-01

    Warm-needling (also called thermo-acupuncture) is a combination of acupuncture and moxibustion. Due to the intense heat involved, there have been concerns over the biological safety of the acuneedles used in the treatment. This paper reports two phases of a safety test. For a preliminary test, we compared the temperature change patterns of stainless steel (SS304) needles and traditional gold alloy needles, which have been increasingly replaced by the former. To verify the effects of the presence of coating materials, the main test involved three different kinds of SS304: silicone-coated, salicylic acid-coated and non-coated needles. Each group of needles was tested for pH level, heavy metals and UV absorbance spectrum along with biological tests on the cytotoxicity and hemolysis of the needle. All the tests on the extractants from the needles were negative. In the biological tests, each test result showed a significant difference from the positive control samples, while no significant difference was observed compared with the negative control samples. In the hemolysis tests, all samples satisfied the Korean Government Standards. All the results suggest that SS304 needles are biologically safe to be used in warm-needling, though they can be improved to perform as well as the gold alloy needles in terms of temperature fluctuations. PMID:19098297

  7. Application of martensitic, modified martensitic and duplex stainless steel bar stock for completion equipment

    SciTech Connect

    Bhavsar, R.B. [CAMCO Products and Services, Houston, TX (United States); Montani, R. [Foroni, S.p.A., Colombo (Italy)

    1998-12-31

    Martensitic and duplex stainless steel tubing are commonly used for oil and gas applications containing CO{sub 2}. Completion equipment manufacturing requires use of solid round bar or heavy wall hollows. Material properties for this stock are not identical in all cases. Material properties as well as corrosion characteristics are discussed for 13Cr, 13Cr-5Ni-2Mo and 25Cr alloys. Corrosion testing of modified or Enhanced 13Cr solid bar stock, UNS S41425 and other compositions in H{sub 2}S-Cl{sup {minus}} and pH is reported in coupled and uncoupled condition. Corrosion testing of various super duplex bar stock at various H{sub 2}S-chlorides and temperature in CO{sub 2} environment is reported. Impact value requirements, welding issues and special consideration required for these alloys for completion equipment is discussed. Modified 13Cr and Super Duplex Oil Country Tubular Goods (OCTG) are readily available, however, availability of completion equipment raw material compatible with these OCTG is limited.

  8. Inhibition of Sodium Benzoate on Stainless Steel in Tropical Seawater

    SciTech Connect

    Seoh, S. Y.; Senin, H. B.; Nik, W. N. Wan; Amin, M. M. [Faculty of Science and Technology, University College of Science and Technology Malaysia (KUSTEM), 21030 Kuala Terengganu, Terengganu Darul Iman (Malaysia)

    2007-05-09

    The inhibition of sodium benzoate for stainless steel controlling corrosion was studied in seawater at room temperature. Three sets of sample have been immersed in seawater containing sodium benzoate with the concentrations of 0.3M, 0.6M and 1.0M respectively. One set of sample has been immersed in seawater without adding any sodium benzoate. It was found that the highest corrosion rate was observed for the stainless steel with no inhibitor was added to the seawater. As the concentration of sodium benzoate being increased, the corrosion rate is decreases. Results show that by the addition of 1.0M of sodium benzoate in seawater samples, it giving {>=} 90% efficiencies.

  9. Failure Assessment of Stainless Steel and Titanium Brazed Joints

    NASA Technical Reports Server (NTRS)

    Flom, Yury A.

    2012-01-01

    Following successful application of Coulomb-Mohr and interaction equations for evaluation of safety margins in Albemet 162 brazed joints, two additional base metal/filler metal systems were investigated. Specimens consisting of stainless steel brazed with silver-base filler metal and titanium brazed with 1100 Al alloy were tested to failure under combined action of tensile, shear, bending and torsion loads. Finite Element Analysis (FEA), hand calculations and digital image comparison (DIC) techniques were used to estimate failure stresses and construct Failure Assessment Diagrams (FAD). This study confirms that interaction equation R(sub sigma) + R(sub tau) = 1, where R(sub sigma) and R(sub t u) are normal and shear stress ratios, can be used as conservative lower bound estimate of the failure criterion in stainless steel and titanium brazed joints.

  10. Microstructural evolution of SINQ irradiated austenitic stainless steels

    NASA Astrophysics Data System (ADS)

    Sawai, T.; Kitsunai, Y.; Saito, S.; Kikuchi, K.

    2006-09-01

    A type 316 stainless steel 316F and Ti-modified type 316 stainless steel JPCA irradiated in SINQ were examined using transmission electron microscopy. Estimated irradiation temperatures for two 316F specimens were 250 and 300 °C and that for the JPCA specimen was 255 °C. Irradiation damage of these specimens is calculated to be about 10 dpa. In the 316F specimen irradiated at 300 °C, Frank loops up to 30 nm were observed and larger perfect loops up to 50 nm were observed. Numerous defect clusters smaller than 5 nm were also observed. Stacking fault tetrahedra up to 2 nm were also observed. Dislocation loops up to 20 nm were observed in the JPCA specimen. They are smaller than those observed in 316F and it is reasonable considering the lower irradiation temperature of the JPCA specimen and lower dislocation bias expected in JPCA.

  11. Electrochemical Corrosion Testing of Borated Stainless Steel Alloys

    SciTech Connect

    lister, tedd e; Mizia, Ronald E

    2007-05-01

    The Department of Energy Office of Civilian Radioactive Waste Management has specified borated stainless steel manufactured to the requirements of ASTM A 887-89, Grade A, UNS S30464, to be the material used for the fabrication of the fuel basket internals of the preliminary transportation, aging, and disposal canister system preliminary design. The long-term corrosion resistance performance of this class of borated materials must be verified when exposed to expected YMP repository conditions after a waste package breach. Electrochemical corrosion tests were performed on crevice corrosion coupons of Type 304 B4 and Type 304 B5 borated stainless steels exposed to single postulated in-package chemistry at 60°C. The results show low corrosion rates for the test period

  12. Long-Term Underground Corrosion of Stainless Steels

    SciTech Connect

    M. K. Adler Flitton; T. S. Yoder

    2007-03-01

    In 1970, the National Institute of Standards and Technology (NIST) implemented the most ambitious and comprehensive long-term corrosion behavior test to date for stainless steels in soil environments. Over thirty years later, one of the six test sites was targeted to research subsurface contamination and transport processes in the vadose and saturated zones. This research directly applies to environmental management operational corrosion issues and long term stewardship scientific needs for understanding the behavior of waste forms and their near-field contaminant transport of chemical and radiological contaminants at nuclear disposal sites. This paper briefly describes the ongoing research and the corrosion analysis results of the stainless steel plate specimens recovered from the partial recovery of the first test site.

  13. STAINLESS STEEL INTERACTIONS WITH SALT CONTAINING PLUTONIUM OXIDES

    SciTech Connect

    Nelson, Z.; Chandler, G.; Dunn, K.; Stefek, T.; Summer, M.

    2010-02-01

    Salt containing plutonium oxide materials are treated, packaged and stored within nested, stainless steel containers based on requirements established in the DOE 3013 Standard. The moisture limit for the stored materials is less than 0.5 weight %. Surveillance activities which are conducted to assess the condition of the containers and assure continuing 3013 container integrity include the destructive examination of a select number of containers to determine whether corrosion attack has occurred as a result of stainless steel interactions with salt containing plutonium oxides. To date, some corrosion has been observed on the innermost containers, however, no corrosion has been noted on the outer containers and the integrity of the 3013 container systems is not expected to be compromised over a 50 year storage lifetime.

  14. Emissivity of sodium wetted and oxidized Type 304 stainless steel

    SciTech Connect

    Haines, N.L.; Craig, R.E.; Forsyth, D.R.; Novendstern, E.H.

    1980-01-01

    The emissivity of sodium wetted and oxidized Type 304 stainless steel was determined to provide data for calculating the heat flow through Liquid Metal Fast Breeder Reactor (LMFBR) reflector plates, located above the sodium pool, to the reactor closure head. An emissivity experiment using a Type 304 stainless steel specimen was performed in an inerted glovebox. Relatively high oxygen concentrations of 10,000 and 50 vppm were used in the argon/oxygen mixtures to reduce reaction time. Following wetting and oxidation, the specimen was heated to a maximum temperature of 450/sup 0/C and the emissivity of the oxidized coating was calculated. Results indicate that the emissivity of the coating ranged from 0.55 to 0.92.

  15. Thermal conductivity of Inconel 718 and 304 stainless steel

    SciTech Connect

    Sweet, J.N.; Roth, E.P.; Moss, M.

    1987-07-01

    The results of thermal conductivity measurements on Inconel 718 and 304 stainless steel by the comparative and flash diffusivity techniques are reported for the temperature range 0-700/sup 0/C. For 304 stainless steel, excellent agreement with published data is found for the specific heat, thermal diffusivity, and thermal conductivity. In the case of Inconel 718, the measurements show that the conductivity depends critically on the sample thermal history and the metallurgical condition of the alloy. Measurements on a solution-treated sample indicated a conductivity function close to that reported previously, while precipitated samples showed a higher conductivity, similar to the conductivity-vs-temperature function used for reduction of comparative thermal conductivity data with Inconel 718 references. These results indicate that Inconel 718 is not a suitable reference for high-accuracy comparative thermal conductivity measurements unless its thermal history and associated conductivity function are known.

  16. Mechanical and physical properties of irradiated type 348 stainless steel

    SciTech Connect

    Beeston, J.M.

    1980-01-01

    A type 348 stainless steel in-pile tube irradiated to a fluence of 3 x 10/sup 22/ n/cm/sup 2/, E > 1 MeV (57 dpa), was destructively examined. The service had resulted in a maximum total creep of 1.8% at the high fluence. The metal temperature ranged between 623 and 652/sup 0/K, hence the thermal creep portion of the total was negligible. Total creep was greater than had been anticipated from creep data for austenitic stainless steels irradiated in other reactors. The objectives of the destructive examination were to determine the service-induced changes of mechanical and physical properties, and to assess the possibility of adverse effects of both these changes and the greater total creep on the prospective service life of other tubes.

  17. Microstructural analysis of austenitic stainless steel laser welds

    SciTech Connect

    Vitek, J.M.; David, S.A.

    1981-01-01

    Analysis of laser welded type 308 stainless steel has shown that the high cooling rates encountered in the process have noticeably altered the structures. Results show promise in solving the common problems of hot cracking and elevated temperature embrittlement in austenitic stainless steel welds. The solidification mode is changed from one of primary ferrite formation to primary austenite. This change in solidification mode results in a large reduction in the ferrite level to less than 1%. Although the welds are nearly fully austenitic, no evidence of hot cracking was found. Aging results indicate the little ferrite that does exist in these welds may help avoid the ferrite to sigma transformation. This may be possible because the finer scale of the ferrite reduces the time necessary for complete dissolution of the ferrite in the austenite matrix. 9 figures, 2 tables.

  18. Glow discharge cleaning of carbon fiber composite and stainless steel

    NASA Astrophysics Data System (ADS)

    Airapetov, A.; Begrambekov, L.; Brémond, S.; Douai, D.; Kuzmin, A.; Sadovsky, Ya.; Shigin, P.; Vergasov, S.

    2011-08-01

    The paper experimentally investigates and analyses the features and mechanisms of both of oxygen removal by deuterium glow discharge from CFC, pyrolytic graphite and stainless steel subjected to irradiation in oxygen contaminated plasma. It is shown that oxygen implanted in pyrolytic graphite (PG) perpendicular to basal plates is removed after sputtering the layer slightly thicker than oxygen stopping zone (?2 nm). Fast deuterium ions penetrating into CFC during GDC transfer the trapped oxygen atoms into the bulk. Thus, much thicker surface layer has to be removed (500-1000 nm) for oxygen release. Irradiation of stainless steel in plasma leads to formation of a barrier layer with thickness (2-4 nm) equal, or slightly higher than stopping range of oxygen ions. The layer accumulates the main fraction of implanted oxygen and prevents its penetration into the bulk. After barrier layer sputtering oxygen spreads into the bulk. Parameters and conditions of optimum GDC are discussed.

  19. Milling and Drilling Evaluation of Stainless Steel Powder Metallurgy Alloys

    SciTech Connect

    Lazarus, L.J.

    2001-12-10

    Near-net-shape components can be made with powder metallurgy (PM) processes. Only secondary operations such as milling and drilling are required to complete these components. In the past and currently production components are made from powder metallurgy (PM) stainless steel alloys. process engineers are unfamiliar with the difference in machining properties of wrought versus PM alloys and have had to make parts to develop the machining parameters. Design engineers are not generally aware that some PM alloy variations can be furnished with machining additives that greatly increase tool life. Specimens from a MANTEC PM alloy property study were made available. This study was undertaken to determine the machining properties of a number of stainless steel wrought and PM alloys under the same conditions so that comparisons of their machining properties could be made and relative tool life determined.

  20. Stress corrosion cracking on irradiated 316 stainless steel

    Microsoft Academic Search

    Gen Furutani; Nobuo Nakajima; Takao Konishi; Mitsuhiro Kodama

    2001-01-01

    Tests on irradiation-assisted stress corrosion cracking (IASCC) were carried out by using cold-worked (CW) 316 stainless steel (SS) in-core flux thimble tubes which were irradiated up to 5×1026 n\\/m2 (E>0.1 MeV) at 310°C in a Japanese PWR. Unirradiated thimble tube was also tested for comparison with irradiated tubes. Mechanical tests such as the tensile, hardness tests and metallographic observations were

  1. Reaction of europia with austenitic stainless steel. [LMFBR

    Microsoft Academic Search

    1976-01-01

    The compatibility of EuâOâ, a potential control material for fast reactors, with the prototypic reference cladding alloy, Type 316 stainless steel, for the fast flux test facility and Clinch River Breeder Reactor Plant reactors is characterized at 1093°C. Metallographic examination of the reaction band shows that severe reaction occurred on the surface of the cladding alloy, particularly grain boundary penetration.

  2. Electrochromic enhancement of latent fingerprints on stainless steel surfaces.

    PubMed

    Beresford, Ann L; Hillman, A Robert

    2010-01-15

    The visualization of latent fingerprints on a metallic (stainless steel) surface is described by means of spatially selective deposition of an electrochromic polymer (polyaniline). Inhibition of electrochemical processes on areas of the surface masked by the fingerprint results in polymer deposition generating a negative image of the fingermark. By variation of the applied potential, the polymer optical characteristics can be continuously and reversibly adjusted to optimize visual contrast of the fingerprint. PMID:20025232

  3. Solidification structure in a cast B-bearing stainless steel

    Microsoft Academic Search

    Hanguang Fu; Zhenhua Li; Zhiqiang Jiang; Jiandong Xing

    2007-01-01

    Solidification microstructure of a cast stainless steel containing 1.5–2.5 wt.%B has been examined by means of the optical microscopy (OM), the scanning electron microscopy (SEM), the electron probe microanalyzer (EPMA), energy dispersive X-ray spectrometry (EDS), X-ray diffraction (XRD) and Vickers microhardness. The as-cast microstructure consists of the M2(B,C) borocarbide and the austenite. The borocarbide is continuously distributed over the austenite. There

  4. Environment-Assisted Cracking in Custom 465 Stainless Steel

    Microsoft Academic Search

    E. U. Lee; R. Goswami; M. Jones; A. K. Vasudevan

    2011-01-01

    The influence of cold work and aging on the environment-assisted cracking (EAC) behavior and mechanical properties of Custom\\u000a 465 stainless steel (SS) was studied. Four sets of specimens were made and tested. All specimens were initially solution annealed,\\u000a rapidly cooled, and refrigerated (SAR condition). The first specimen set was steel in the SAR condition. The second specimen\\u000a set was aged to

  5. Superhard Nanocrystalline Homometallic Stainless Steel on Steel for Seamless Coatings

    NASA Technical Reports Server (NTRS)

    Tobin, Eric J.; Hafley, R. (Technical Monitor)

    2002-01-01

    The objective of this work is to deposit nanocrystalline stainless steel onto steel substrates (homometallic) for enhanced wear and corrosion resistance. Homometallic coatings provide superior adhesion, and it has been shown that ultrafine-grained materials exhibit the increased hardness and decreased permeability desired for protective coatings. Nanocrystals will be produced by controlling nucleation and growth and use of an ion beam during deposition by e-beam evaporation or sputtering. Phase I is depositing 31 6L nanocrystalline stainless steel onto 31 6L stainless steel substrates. These coatings exhibit hardnesses comparable to those normally obtained for ceramic coatings such ZrO2, and possess the superior adhesion of seamless, homometallic coatings. Hardening the surface with a similar material also enhances adhesion, by avoiding problems associated with thermal and lattice mismatch. So far we have deposited nanocrystalline homometallic 316L stainless steel coatings by varying the ions and the current density of the ion beams. For all deposition conditions we have produced smooth, uniform, superhard coatings. All coatings exhibit hardness of at least 200% harder than that of bulk materials. Our measurements indicate that there is a direct relationship between nanohardness and the current density of the ion beam. Stress measurements indicate that stress in the films is increasingly proportional to current density of the ion beam. TEM, XPS, and XRD results indicate that the coated layers consist of FCC structure nanocrystallites with a dimension of about 10 to 20 nm. The Ni and Mo concentration of these coating are lower than those of bulk 316L but the concentration of Cr is higher.

  6. Fabrication of stainless steel foil utilizing chromized steel strip

    Microsoft Academic Search

    Edward A. Loria

    1980-01-01

    Stainless steel foil has properties which are, in many respects, unmatched by alternative thin films. The high strength to\\u000a weight ratio and resistance to corrosion and oxidation at elevated temperatures are generally advantageous. The aerospace\\u000a and automotive industries have used Type 430 and 304 foil in turbine engine applications. Foil around 2 mils (5.1 ? 10-3 cm) thick has been

  7. Austenitic solidification mode in austenitic stainless steel welds

    Microsoft Academic Search

    T. Takalo; N. Suutala; T. Moisio

    1979-01-01

    The micro- and macrostructures of about 50 different stainless welds of the AISI\\/AWS 300 series are analyzed. The results\\u000a indicate that in welding condition corresponding to a typical SMA welding those and only those welds in which the ratio Creq\\/Nieq?1.48, where Nieq and Creq are the nickel and chromium equivalents on the Schaeffler diagram, solidify with the austenite as the

  8. Functional silica film on stainless steel mesh with tunable wettability

    Microsoft Academic Search

    Hao Yang; Xingjuan Zhang; Zhi-Qi Cai; Pihui Pi; Dafeng Zheng; Xiufang Wen; Jiang Cheng; Zhuo-ru Yang

    2011-01-01

    A series of functional silica films on stainless steel meshes are fabricated by simple sol–gel process using tetraethyl orthosilicate (TEOS) and methyltriethoxysilane (MTES) as precursors and post-thermal treatment or hydrophobization. The wettabilities of these meshes can range from superhydrophobicity and superoleophilicity to superamphiphilicity or amphiphobicity. The tunable wetting states are controlled by changing surface chemistry or morphology. Firstly, methyl-endcapped silica

  9. The formation of phosphate coatings on nitrided stainless steel

    Microsoft Academic Search

    J Flis; J Ma?kowski; T Zakroczymski; T Bell

    2001-01-01

    X10Cr18Ni9Ti stainless steel was plasma nitrided at 600°C or 575°C for 9 h and then subjected to the phosphating in zinc and manganese\\/iron phosphate baths. Depth profile analysis by glow discharge optical emission spectrometry (GDOES) showed that the coatings obtained in the Mn\\/Fe phosphate bath were about 10 ?m thick and were enriched in chromium. Surface analyses by GDOES and

  10. Rapid solidification of a droplet-processed stainless steel

    Microsoft Academic Search

    Thomas F. Kelly; Morris Cohen; John B. vander Sande

    1984-01-01

    Individual powder particles of a droplet-processed and rapidly solidified 303 stainless steel are characterized in terms of\\u000a microstructure and composition variations within the solidification structure using scanning transmission electron microscopy\\u000a (STEM). Fcc is found to be the crystallization phase in powder particles larger than about 70 micron diameter, and bcc is\\u000a the crystallization phase in the smaller powder particles. An

  11. Welding stainless steels for structures operating at liquid helium temperature

    Microsoft Academic Search

    Witherell

    1980-01-01

    Superconducting magnets for fusion energy reactors require massive monolithic stainless steel weldments which must operate at extremely low temperatures under stresses approaching 100 ksi (700 MPa). A three-year study was conducted to determine the feasibility of producing heavy-section welds having usable levels of strength and toughness at 4.2°K for fabrication of these structures in Type 304LN plate. Seven welding processes

  12. Hydrogen-related phase transformations in austenitic stainless steels

    Microsoft Academic Search

    N. Narita; C. J. Altstetter; H. K. Birnbaum

    1982-01-01

    The effect of hydrogen and stress (strain) on the stability of the austenite phase in stainless steels was investigated. Hydrogen was introduced by severe cathodic charging and by elevated temperature equilibration with high pressure H2 gas. Using X-ray diffraction and magnetic techniques, the behavior of two ``stable'' type AISI310 steels and an ``unstable'' type AISI304 steel was studied during charging

  13. Hydrogen-related phase transformations in austenitic stainless steels

    Microsoft Academic Search

    N. Narita; C. J. Altstetter; H. K. Birnbaum

    1982-01-01

    The effect of hydrogen and stress (strain) on the stability of the austenite phase in stainless steels was investigated. Hydrogen\\u000a was introduced by severe cathodic charging and by elevated temperature equilibration with high pressure H2 gas. Using X-ray diffraction and magnetic techniques, the behavior of two “stable” type AISI310 steels and an “unstable”\\u000a type AISI304 steel was studied during charging

  14. Stainless steel microbeads coated with sulfonated polystyrene-co-divinylbenzene

    Microsoft Academic Search

    Cristina Martin; Liliana Ramirez; Jorge Cuellar

    2003-01-01

    A new kind of gel-type magnetic cation-exchange resin based on stainless steel microspheres coated with sulfonated polystyrene-co-divinylbenzene has been synthesized in a two-step process. First, magnetic polymeric beads were prepared by radical suspension polymerization, after which these particles were functionalized by a post-polymerization sulfonation process. The effects of slight modifications in the synthesis process (metal surface modification, initial contact between

  15. Fatigue crack propagation in austenitic stainless steel weldments

    Microsoft Academic Search

    J. T. Al-Haidary; A. A. Wahab; E. H. Abdul Salam

    2006-01-01

    The fatigue crack propagation rate (FCPR) in 316L austenitic stainless steel (ASS) and its weldments was investigated, at\\u000a two loading amplitudes, 7 and 8.5 kN, under tension-tension mode. Two welding techniques, submerged arc welding (SAW) and\\u000a manual arc welding (MAW), have been used. Magnetic ?-ferrite, depending upon Ni and Cr content in the metal, in the weld zone\\u000a upon solidification

  16. Substitution of manganese and nitrogen for nickel in stainless steels

    Microsoft Academic Search

    A. A. Babakov

    1961-01-01

    1.Added nitrogen promotes the formation of austenite in chrome-nickel stainless steels of the austenite class.2.In order to keep the nitrogen in the steel, attempts must be made to form stable nitrides with a high dissociation point. Among such nitrides are chromium nitrides. It has been found that manganese has a positive effect and improves the solubility of nitrogen in steel.3.Nitrogen

  17. Elevated temperature fracture toughness of AISI 403 martensitic stainless steel

    NASA Astrophysics Data System (ADS)

    Dubey, J. S.; Wadekar, S. L.; Chakravartty, J. K.

    1998-04-01

    The AISI 403 martensitic stainless steel is used as the end fitting material in pressurised heavy water reactors. The fracture toughness of single quenched and tempered, double quenched and tempered, and Nb-modified variety of this steel has been evaluated at 473 and 573 K. Elevated temperature results are compared with the room temperature values reported in earlier studies. The double quenched and tempered and Nb-modified structures show higher toughness and d J/d a values at elevated temperatures.

  18. Manganese-stabilized austenitic stainless steels for fusion applications

    DOEpatents

    Klueh, Ronald L. (Knoxville, TN); Maziasz, Philip J. (Oak Ridge, TN)

    1990-01-01

    An austenitic stainless steel that is comprised of Fe, Cr, Mn, C but no Ni or Nb and minimum N. To enhance strength and fabricability minor alloying additions of Ti, W, V, B and P are made. The resulting alloy is one that can be used in fusion reactor environments because the half-lives of the elements are sufficiently short to allow for handling and disposal.

  19. Non-equilibrium solidification in austenitic stainless steel welds

    Microsoft Academic Search

    J. M. Vitek; S. A. David

    1991-01-01

    Recent studies have shown that non-equilibrium solidification may occur in a wide range of stainless steel alloy compositions. The non-equilibrium microstructures that are found are commonly produced in laser and electron beam-welded materials but they can also be observed, in some cases, in welds produced by conventional arc welding. In general, non-equilibrium solidification extends the range of compositions in which

  20. Nitriding of austenitic stainless steel by plasma immersion ion implantation

    Microsoft Academic Search

    G. A. Collins; R. Hutchings; K. T. Short; J. Tendys; X. Li; M. Samandi

    1995-01-01

    Plasma immersion ion implantation (PI3™), in which the diffusion of nitrogen from a low pressure r.f. plasma is combined with the implantation of nitrogen ions at energies up to 45 kV, is an effective means of nitriding austenitic stainless steel. At temperatures up to 450 °C, tribological properties can be improved without loss of corrosion resistance. In common with other

  1. Laser surface modification of stainless steels for cavitation erosion resistance

    Microsoft Academic Search

    Chi Tat Kwok

    1999-01-01

    Austenitic stainless steel UNS S31603 (Fe -17.6Cr -11.2Ni -2.5Mo -1.4Mn -0.4Si -0.03C) has higher pitting corrosion resistance but lower cavitation erosion resistance than that of UNS S30400. This is because of its lower tendency for strain induced martensitic transformation and higher stacking fault energy as compared with those of UNS S30400. In order to improve its cavitation erosion resistance, surface

  2. Measurement of Creep Deformation in Stainless Steel Welded Joints

    Microsoft Academic Search

    Y. Sakanashi; S. Gungor; P. J. Bouchard

    \\u000a This article reports early findings of an experimental programme aimed at determining local creep properties of welded joints\\u000a made from AISI Type 316H austenitic stainless steel. For this purpose, 3 mm thick, flat cross-weld specimens were cut from\\u000a a pipe and subjected to creep testing at 550°C. In order to determine local creep properties around the weld within the gauge

  3. Electrochemical repairing of pitted 18-8 stainless steel

    Microsoft Academic Search

    H. P. Duan; Y. C. Li; C. W. Yan

    2005-01-01

    In order to clarify the reaction essential of electrochemical repairing method, which was developed to repair the passive\\u000a film on pits and suppress pitting corrosion on passive 18-8 stainless steel (18-8ss) after occurrence of pitting, the electrochemical\\u000a characteristics, morphology and composition of passive film after different treatments were investigated by electrochemical\\u000a impedance spectroscopy (EIS), Cyclic Voltammogram (CV), Scanning electron microscopy

  4. Carbides in low-temperature-carburized stainless steels

    Microsoft Academic Search

    F Ernst; Y Cao; G. M Michal

    2004-01-01

    A novel, low-temperature (470 °C) gas-phase carburization treatment, developed by the Swagelok Company, increases the surface hardness of 316-type austenitic stainless steels from ?200 to ?1000HV25 via a colossal supersaturation of up to 12 at.% carbon in solid solution. Upon extended treatment, carbide precipitation does eventually occur. Transmission electron microscopy of carburized bulk, foil, and powder samples has revealed two

  5. Corrosion behavior of ion nitrided AISI 316L stainless steel

    Microsoft Academic Search

    L. Nosei; S. Farina; M. Ávalos; L. Nachez; B. J. Gómez; J. Feugeas

    2008-01-01

    In the present work the corrosion susceptibility of ion nitrided AISI 316L stainless steel was investigated for two different nitriding times and compared with the corrosion susceptibility of the untreated material. Plasma nitriding for short times (30 min) produced the “S” phase or expanded austenite (?N), with a thickness of ?5 ?m and a micro-hardness of 1300–1400 HV0.025 (6.5 times higher than

  6. Corrosion Testing of Stainless Steel Fuel Cell Hardware

    SciTech Connect

    Wilson, M.S.; Zawodzinski, C.; Gottesfeld, S.

    1998-11-01

    Metal hardware is gaining increasing interest in polymer electrolyte fuel cell (PEFC) development as a possible alternative to machined graphite hardware because of its potential for low-cost manufacturing combined with its intrinsic high conductivity, minimal permeability and advantageous mechanical properties. A major barrier to more widespread use of metal hardware has been the susceptibility of various metals to corrosion. Few pure metals can withstand the relatively aggressive environment of a fuel cell and thus the choices for hardware are quite limited. Precious metals such as platinum or gold are prohibitively expensive and so tend to be utilized as coatings on inexpensive substrates such as aluminum or stainless steel. The main challenge with coatings has been to achieve pin-hole free surfaces that will remain so after years of use. Titanium has been used to some extent and though it is very corrosion-resistant, it is also relatively expensive and often still requires some manner of surface coating to prevent the formation of a poorly conducting oxide layer. In contrast, metal alloys may hold promise as potentially low-cost, corrosion-resistant materials for bipolar plates. The dozens of commercially available stainless steel and nickel based alloys have been specifically formulated to offer a particular advantage depending upon their application. In the case of austenitic stainless steels, for example, 316 SS contains molybdenum and a higher chromium content than its more common counterpart, 304 SS, that makes it more noble and increases its corrosion resistance. Likewise, 316L SS contains less carbon than 316 SS to make it easier to weld. A number of promising corrosion-resistant, highly noble alloys such as Hastelloy{trademark} or Duplex{trademark} (a stainless steel developed for seawater service) are available commercially, but are expensive and difficult to obtain in various forms (i.e. wire screen, foil, etc.) or in small amounts for R and D purposes.

  7. Advanced soft magnetic stainless steel for electric fuel injector

    Microsoft Academic Search

    Y. Honkura; H. Fujii; K. Hayasi

    1989-01-01

    An improved soft magnetic stainless steel has been developed which is effective in the response of electric fuel injectors. The chemical compositions of this steel is 10%Cr-3%Al-0.2%Pb. The steel provides 25% better magnetic response to pulse signal and 40% larger specific resistance than a soft magnetic 13%Cr-0.8%Si steel which is previously used for the core of electric fuel injectors. In

  8. Prediction of fatigue crack formation in 304 stainless steel

    Microsoft Academic Search

    Shaun M. Mcguire; Morris E. Fine

    1996-01-01

    Strain-controlled fatigue tests have been conducted on center-holed 304 stainless steel specimens. The fraction of total fatigue\\u000a life spent until formation of an “engineering” crack ranged from about 15 to 85 pct, indicating the potential importance of\\u000a being able to predict the fatigue crack formation life. A “just formed engineering crack,” as defined here, is a through crack\\u000a long in

  9. Attack polish for nickel-base alloys and stainless steels

    DOEpatents

    Steeves, Arthur F. (Schenectady, NY); Buono, Donald P. (Schenectady, NY)

    1983-01-01

    A chemical attack polish and polishing procedure for use on metal surfaces such as nickel base alloys and stainless steels. The chemical attack polish comprises Fe(NO.sub.3).sub.3, concentrated CH.sub.3 COOH, concentrated H.sub.2 SO.sub.4 and H.sub.2 O. The polishing procedure includes saturating a polishing cloth with the chemical attack polish and submicron abrasive particles and buffing the metal surface.

  10. Method of polishing nickel-base alloys and stainless steels

    DOEpatents

    Steeves, Arthur F. (Schenectady, NY); Buono, Donald P. (Schenectady, NY)

    1981-01-01

    A chemical attack polish and polishing procedure for use on metal surfaces such as nickel base alloys and stainless steels. The chemical attack polish comprises Fe(NO.sub.3).sub.3, concentrated CH.sub.3 COOH, concentrated H.sub.2 SO.sub.4 and H.sub.2 O. The polishing procedure includes saturating a polishing cloth with the chemical attack polish and submicron abrasive particles and buffing the metal surface.

  11. Weld-cracking mechanisms in austenitic stainless steels

    Microsoft Academic Search

    Lippold

    1982-01-01

    The hot cracking susceptibility of several austenutuc stainless steel filler wires and a Type 304L base material has been evaluated using both the VARESTRAINT Test and a modified patch test. In general, alloys which solidified with ferrite as the primary phase and contained 5-12 volume percent ferrite in the as-welded microstructure were more resistant to cracking than alloys which solidified

  12. On the stress corrosion cracking mechanisms of austenitic stainless steels

    Microsoft Academic Search

    P Rodriguez; H S Khatak; J B Gnanamoorthy

    1994-01-01

    In this paper, experimental results on stress corrosion cracking in austenitic stainless steels are described. Crack growth\\u000a data in sodium chloride solution for AISI 304 steel obtained for different metallurgical conditions, acoustic emission data\\u000a recorded during crack growth and fractographic observations have been discussed with a view to identifying the operating mechanism.\\u000a Some of the experimental observations such as crack

  13. Microstructural Evolution in Adiabatic Shear Localization in Stainless Steel

    Microsoft Academic Search

    M. A. Meyers; M. T. Perez-Prado; Q. Xue; Y. Xu; T. R. McNelley

    2002-01-01

    Shear bands were generated under prescribed and controlled conditions in stainless steel (Fe-18%Cr-8%Ni). Hat-shaped specimens, deformed in a Hopkinson bar were used, yielding strain rates of approximately 104s-1 and shear strains that could be varied between 1 and 100. Specimens recovered from the collapse of thick-walled cylinders were also investigated. Microstructural characterization was performed by electron backscattered diffraction (EBSD) with

  14. Microstructural Evolution in Adiabatic Shear Localization in Stainless Steel

    Microsoft Academic Search

    M. A. Meyers; M. T. Perez-Prado; Q. Xue; Y. Xu; T. R. McNelley

    2002-01-01

    Shear bands were generated under prescribed and controlled conditions in stainless steel (Fe-18%Cr-8%Ni). Hat-shaped specimens, deformed in a Hopkinson bar were used, yielding strain rates of approximately 104s?1 and shear strains that could be varied between 1 and 100. Specimens recovered from the collapse of thick-walled cylinders were also investigated. Microstructural characterization was performed by electron backscattered diffraction (EBSD) with

  15. Microstructural evolution in adiabatic shear localization in stainless steel

    Microsoft Academic Search

    M. A. Meyers; Y. B. Xu; Q. Xue; M. T. Pérez-Prado; T. R. McNelley

    2003-01-01

    Shear bands were generated under prescribed and controlled conditions in an AISI 304L stainless steel (Fe–18%Cr–8%Ni). Hat-shaped specimens were deformed in a Hopkinson bar at strain rates of ca 104 s?1 and shear strains that could be varied between 1 and 100. Microstructural characterization was performed by electron backscattered diffraction (EBSD) with orientation imaging microscopy (OIM), and transmission electron microscopy

  16. Attack polish for nickel-base alloys and stainless steels

    DOEpatents

    Not Available

    1980-05-28

    A chemical attack polish and polishing procedure for use on metal surfaces such as nickel base alloys and stainless steels is described. The chemical attack polich comprises FeNO/sub 3/, concentrated CH/sub 3/COOH, concentrated H/sub 2/SO/sub 4/ and H/sub 2/O. The polishing procedure includes saturating a polishing cloth with the chemical attack polish and submicron abrasive particles and buffing the metal surface.

  17. Analytical electron microscopy of stainless steel weld metal

    Microsoft Academic Search

    Lyman

    1979-01-01

    The technique of analytical electron microscopy in a Scanning Transmission Electron Microscope (STEM) fitted with an x-ray spectrometer is described. This high spatial resolution microanalysis technique is applied to duplex Type 304L stainless steel weld metal. Small inclusions in these steels may be either iron-rich or manganese-rich silicates and may contain small amounts of elements not listed in the normal

  18. pH Optrode Instrumentation

    NASA Technical Reports Server (NTRS)

    Tabacco, Mary Beth; Zhou, Quan

    1995-01-01

    pH-sensitive chromophoric reagents immobilized in porous optical fibers. Optoelectronic instrumentation system measures acidity or alkalinity of aqueous nutrient solution. Includes one or more optrodes, which are optical-fiber chemical sensors, in sense, analogous to electrodes but not subject to some of spurious effects distorting readings taken by pH electrodes. Concept of optrodes also described in "Ethylene-Vapor Optrodes" (KSC-11579). pH optrode sensor head, with lead-in and lead-out optical fibers, convenient for monitoring solutions located away from supporting electronic equipment.

  19. PhET: Masses & Springs

    NSDL National Science Digital Library

    This simulation provides a realistic virtual mass-and-spring laboratory. Users can explore spring motion by manipulating stiffness of the spring and mass of the hanging weight. Concepts of Hooke's Law and elastic potential energy are further clarified through charts showing kinetic, potential, and thermal energy for each spring. This item is part of a larger collection of simulations developed by the Physics Education Technology project (PhET). The simulations are animated, interactive, and game-like environments in which students learn through exploration. All of the sims are freely available from the PhET website for incorporation into classes.

  20. Impact Testing of Stainless Steel Material at Cold Temperatures

    SciTech Connect

    Spencer D. Snow; D. Keith Morton; Robert K. Blandford

    2008-07-01

    Stainless steels are used for the construction of numerous spent nuclear fuel or radioactive material containers that may be subjected to high strains and moderate strain rates during accidental drop events. Mechanical characteristics of these base materials and their welds under dynamic loads in the strain rate range of concern are not well documented. However, a previous paper [1] reported on impact testing and analysis results performed at the Idaho National Laboratory using 304/304L and 316/316L stainless steel base material specimens at room and elevated temperatures. The goal of the work presented herein is to add recently completed impact tensile testing results at -20 degrees F conditions for dual-marked 304/304L and 316/316L stainless steel material specimens (hereafter referred to as 304L and 316L, respectively). Recently completed welded material impact testing at -20 degrees F, room, 300 degrees F, and 600 degrees F is also reported. Utilizing a drop-weight impact test machine and 1/4-inch to 1/2-inch thick dog-bone shaped test specimens, the impact tests achieved strain rates in the 4 to 40 per second range, depending upon the material temperature. Elevated true stress-strain curves for these materials reflecting varying strain rates and temperatures are presented herein.

  1. Iodine susceptibility of pseudomonads grown attached to stainless steel surfaces

    NASA Technical Reports Server (NTRS)

    Pyle, B. H.; McFeters, G. A.

    1990-01-01

    Pseudomonads were adapted to grow in phosphate-buffered water and on stainless steel surfaces to study the iodine sensitivity of attached and planktonic cells. Cultures adapted to low nutrient growth were incubated at room temperature in a circulating reactor system with stainless steel coupons to allow biofilm formation on the metal surfaces. In some experiments, the reactor was partially emptied and refilled with buffer at each sampling time to simulate a "fill-and-draw" water system. Biofilms of attached bacteria, resuspended biofilm bacteria, and reactor suspension, were exposed to 1 mg l-1 iodine for 2 min. Attached bacterial populations which established on coupons within 3 to 5 days displayed a significant increase in resistance to iodine. Increased resistance was also observed for resuspended cells from the biofilm and planktonic bacteria in the system suspension. Generally, intact biofilms and resuspended biofilm cells were most resistant, followed by planktonic bacteria and phosphate buffer cultures. Thus, biofilm formation on stainless steel surfaces within water systems can result in significantly increased disinfection resistance of commonly-occurring water-borne bacteria that may enhance their ability to colonise water treatment and distribution systems.

  2. Reducing tool wear when machining austenitic stainless steels

    SciTech Connect

    Magee, J.H.; Kosa, T.

    1998-07-01

    Austenitic stainless steels are considered more difficult to machine than carbon steels due to their high work hardening rate, large spread between yield and ultimate tensile strength, high toughness and ductility, and low thermal conductivity. These characteristics can result in a built-up edge or excessive tool wear during machining, especially when the cutting speed is too high. The practical solution is to lower the cutting speed until tool life reaches an acceptable level. However, lower machining speed negatively impacts productivity. Thus, in order to overcome tool wear at relatively high machining speeds for these alloys, on-going research is being performed to improve cutting fluids, develop more wear-resistant tools, and to modify stainless steels to make them less likely to cause tool wear. This paper discusses compositional modifications to the two most commonly machined austenitic stainless steels (Type 303 and 304) which reduced their susceptibility to tool wear, and allowed these grades to be machined at higher cutting speeds.

  3. Surface interactions of cesium and boric acid with stainless steel

    SciTech Connect

    Grossman-Canfield, N.

    1995-08-01

    In this report, the effects of cesium hydroxide and boric acid on oxidized stainless steel surfaces at high temperatures and near one atmosphere of pressure are investigated. This is the first experimental investigation of this chemical system. The experimental investigations were performed using a mass spectrometer and a mass electrobalance. Surfaces from the different experiments were examined using a scanning electron microscope to identify the presence of deposited species, and electron spectroscopy for chemical analysis to identify the species deposited on the surface. A better understanding of the equilibrium thermodynamics, the kinetics of the steam-accelerated volatilizations, and the release kinetics are gained by these experiments. The release rate is characterized by bulk vaporization/gas-phase mass transfer data. The analysis couples vaporization, deposition, and desorption of the compounds formed by cesium hydroxide and boric acid under conditions similar to what is expected during certain nuclear reactor accidents. This study shows that cesium deposits on an oxidized stainless steel surface at temperatures between 1000 and 1200 Kelvin. Cesium also deposits on stainless steel surfaces coated with boric oxide in the same temperature ranges. The mechanism for cesium deposition onto the oxide layer was found to involve the chemical reaction between cesium and chromate. Some revaporization in the cesium hydroxide-boric acid system was observed. It has been found that under the conditions given, boric acid will react with cesium hydroxide to form cesium metaborate. A model is proposed for this chemical reaction.

  4. Recrystallization and Grain Growth of 316L Stainless Steel Wires

    NASA Astrophysics Data System (ADS)

    Zhao, Xiuyun; Liu, Yong; Wang, Yan; Feng, Ping; Tang, Huiping

    2014-07-01

    Recrystallization and grain growth behaviors of 316L stainless steel wires with a diameter of 12 µm were investigated by optical microscopy, scanning electron microscopy, transmission electron microscopy (TEM), and X-ray diffraction techniques. Heavily cold-drawn wires were isothermally held at temperatures from 1073 K to 1223 K (800 °C to 950 °C) for various holding times. Optical microscopy and TEM observations showed that recrystallization grains have irregular shape and that twins exist. The texture formed during drawing and annealing processes of the wires, as measured by X-ray methods, showed a fiber texture approximated by a <111> and a <100> component. The value of the grain growth exponent n was calculated, and the kinetic rates were plotted using the Arrhenius equation. Results show that the activation energy of the grain growth for 316L stainless steel wire was determined to be 407 kJ/mol, which was much higher than that of the bulk 316L stainless steel. The small wire diameter and the existence of texture played important roles in the increase of the activation energy for grain growth of the wire.

  5. Revisiting the crevice corrosion of stainless steel and aluminum in chloride solutions---The role of electrode potential

    NASA Astrophysics Data System (ADS)

    Deforce, Brian S.

    Although the crevice corrosion of stainless steel and aluminum in chloride solutions has been studied extensively, there is little agreement on the mechanism of crevice corrosion for these materials. The present study attempted to resolve the ambiguity of the crevice corrosion mechanism by first reviewing previous relevant studies and then, by conducting an in-depth study of crevice corrosion with a focus on electrode potential and the IR mechanism. The crevice corrosion of aluminum (99.999 wt. %, AA2024) and stainless steel (304 and 444) in neutral and mildly acidic chloride solutions was investigated. For each alloy system, polarization curves were generated in simulated crevice solutions and potentiostatic crevice corrosion experiments with varying crevice gap opening dimensions were performed. Current and electrode potential along the crevice wall were measured. In-situ photographs of the developing crevice corrosion were obtained and in-situ and ex-situ pH measurements were performed. For the stainless steels, potentiodynamic and potentiostatic methods, including a novel applied potential shift method, were used in an attempt of detect the development of an anodic peak in a passive system, prior to the onset of crevice corrosion. Crevice corrosion of aluminum in a pH 6, 0.6M NaCl solution was not found to occur under open circuit or polarized conditions. Polarization curves in simulated crevice solutions did not show an anodic peak. Based on the polarization behavior, the IR mechanism correctly predicts the absence of crevice corrosion for this system. Crevice corrosion was observed for aluminum in a mildly acidic (pH 3), chloride free solution and found to be consistent with the IR mechanism. In this solution, crevice corrosion resulting in severe material loss was observed and a high current (10 mA) was measured. This is the first time crevice corrosion of aluminum, as indicated by significant material loss and high measured current, has been reported. Also of importance, is the fact that the corrosion occurred in the absence of pitting corrosion. The cause of corrosion in this case can be explained by alkalization of the crevice due to a high rate of hydrogen evolution reaction, driven by a potential drop within the crevice. For stainless steels, crevice corrosion was clearly demonstrated in a neutral 0.6M NaCl solution and in two mildly acidic simulated crevice solutions: pH 2, 0.6M NaCl and pH 1, 3M NaCl. The conclusive evidence of the occurrence of crevice corrosion was a high measured current and photographic evidence of showing severe material loss within the crevice and no attack on the uncreviced surfaces. All observations of the propagation of crevice corrosion for 304 and 444 were consistent with the IR mechanism. Additional efforts to understand the mechanism of stainless steel crevice corrosion focused on studying the initiation. No evidence was found to suggest initiation occurs due to a reduction of the pitting potential from chloride accumulation. Initiation of crevice corrosion was found to occur after the development of an anodic peak. This is the first time an anodic peak has been detected prior to the onset of crevice corrosion. This novel observation provides proof that an anodic peak can develop in a passive system. Since the IR mechanism requires an anodic peak, this observation provides convincing evidence for the applicability of IR mechanism in a passive system. Equally important, the observation shows that while compositional change is required to develop the anodic peak, another step is necessary to initiate crevice corrosion. Crevice corrosion mechanisms that rely solely on compositional change are inadequate in that they do not provide an explanation for the additional step. However, the IR mechanism clearly defines this additional step as the initiation event, IR>Deltaphi*, at which point the crevice wall in contact with the acidified crevice solution is activated and crevice corrosion begins. In summary, crevice corrosion of aluminum and stainless steels was clearly demonstrated

  6. Ph.D. Requirements Fall, 2009 and Forward Approved Ph.D. Training Requirements

    E-print Network

    Acton, Scott

    Ph.D. Requirements Fall, 2009 and Forward 1 Approved Ph.D. Training Requirements Requirements effective for Ph.D. programs enrolling students in Fall 2009 and forward Critical Outcomes of a Research-Oriented Ph.D. Program In terms of an overall vision of the Curry Ph.D. graduate, the aims include student

  7. Stress corrosion cracking of stainless steels in NaCl solutions

    Microsoft Academic Search

    Markus O. Speidel

    1981-01-01

    The metallurgical influences on the stress corrosion resistance of many commercial stainless steels have been studied using\\u000a the fracture mechanics approach. The straight-chromium ferritic stainless steels, two-phase ferritic-austenitic stainless\\u000a steels and high-nickel solid solutions (like alloys 800 and 600) investigated are all fully resistant to stress corrosion\\u000a cracking at stress intensity (K1) levels ? MN • m-3\\/2 in 22 pct

  8. Stainless steels with improved strength for service at 760 C and above

    SciTech Connect

    Swindeman, R.W.

    1998-03-01

    An evaluation was undertaken of modified 25Cr-20Ni stainless steels and a modified 20Cr-25Ni-Nb stainless steel for advanced energy applications at 760 C (1,400 F) and higher. It was found that good fabricability, strength, and ductility could be produced in the modified steels. Stress rupture data to beyond 10,000 h showed that the strengths of the modified steels were more than double that for type 310H stainless steel.

  9. Dissimilar lap joining of 304 stainless steel to CP-Ti employing friction stir welding

    Microsoft Academic Search

    M. Fazel-Najafabadi; S. F. Kashani-Bozorg; A. Zarei-Hanzaki

    2011-01-01

    A 304 stainless steel plate was lap joined to a CP-Ti one by friction stir welding technique. Stainless steel was selected as the top member. Sound dissimilar joints were achieved using an advancing speed of 50mm\\/min and rotation speeds in the range of 700–1100rpm. A region of vortices of bimetallic weld of 304 stainless steel and CP-Ti was formed in

  10. Stainless steel corrosion products cause alterations on mouse spleen cellular populations

    Microsoft Academic Search

    R. B. Tracana; M. L. Pereira; A. M. Abreu; J. P. Sousa; G. S. Carvalho

    1995-01-01

    Stainless steel is a metallic biomaterial commonly used in orthopaedic surgery. In this study we looked at the effects of stainless steel corrosion products on spleen, in order to evaluate their potential immunotoxicological effects. For this purpose stainless steel, type AISI 316L, was electrochemicallydissolved in a physiological salt solution. The final solution, containing 490 µg\\/ml Fe, 224 µg\\/ml Cr and

  11. Oxidation behavior of a fine-grained rapidly solidified 18-8 stainless steel

    Microsoft Academic Search

    G. J. Yurek; D. Eisen; A. Garratt-Reed

    1982-01-01

    The cyclic oxidation behavior of a fine-grained, rapidly solidified 303 stainless steel was determined at 900 ?C in pure oxygen.\\u000a The rapidly solidified alloy exhibited superior resistance to oxidation compared with that of a wrought 304 stainless steel;\\u000a its oxidation resistance was as good as that of a wrought 310 stainless steel, even though the latter alloy contained more\\u000a Cr

  12. Particle Impact Ignition Test Data on a Stainless Steel Hand Valve

    NASA Technical Reports Server (NTRS)

    Peralta, Stephen

    2010-01-01

    This slide presentation reviews the particle impact ignition test of a stainless steel hand valve. The impact of particles is a real fire hazard with stainless steel hand valves, however 100 mg of particulate can be tolerated. Since it is unlikely that 100 mg of stainless steel contaminant particles can be simultaneously released into this type of valve in the WSTF configuration, this is acceptable and within statistical confidence as demonstrated by testing.

  13. Measurement of Helium Production Cross Sections of Stainless Steels for 14 MeV Neutrons

    Microsoft Academic Search

    Yoshiyuki TAKAO; Yukinori KANDA; Yuji UENOHARA; Tsuyoshi TAKAHASHI; Shigeki ITADANI; Toshiyuki IIDA; Akito TAKAHASHI

    1997-01-01

    Helium production cross sections of the austenitic stainless steels, Type 316 stainless steel, JPCA, and JPCA2, and the ferritic\\/martensitic stainless steels, HT-9, and JFMS have been measured for 14.5MeV neutrons, employing a helium accumulation method. The measured effective cross sections range from 52 to 59 mb with ±8% error and have been compared with the composite values which are calculated

  14. Resistance of nitrogen-containing stainless alloys to corrosion in chloride media

    SciTech Connect

    Bandy, R.; van Rooyen, D.

    1982-10-08

    The pitting resistance of a series of experimental stainless steels with varying amounts of nickel, chromium, molybdenum, manganese and nitrogen and a number of commercial stainless steels and nickel based alloys has been studied in highly concentrated chloride media. The results show that nitrogen enhancer the pitting resistance of stainless steel and exceptional corrosion resistance is achieved with high levels of nitrogen in combination with suitable amounts of molybdenum and chromium.

  15. Environmentally assisted cracking behavior of single and dual phase stainless steels in hot chloride solutions

    Microsoft Academic Search

    Chuan-Ming Tseng; Wen-Ta Tsai

    2004-01-01

    The environmentally assisted cracking (EAC) behavior of AISI 316L austenitic stainless steel (SS), AISI 430 ferritic stainless steel and 22% Cr duplex stainless steel (DSS) in hot chloride solutions were investigated. Slow strain rate testing (SSRT) technique was employed to evaluate the susceptibility to EAC in 3.5wt.% NaCl solution at 80°C and in 40wt.% CaCl2 solution at 100°C. The experimental

  16. Austenitic-ferritic stainless steels: A state-of-the-art review

    Microsoft Academic Search

    B. I. Voronenko

    1997-01-01

    Austenitic-ferritic stainless steels, more commonly known as duplex stainless steels, or DSS for short, consist of two basic\\u000a phases. One is austenite, A, and the other is ferrite, F, present in about equal amounts (but not less than 30% each). The\\u000a two phases owe their corrosion resistance to the high chromium content. Compared to austenitic stainless steels, ASS, they\\u000a are

  17. Forming characteristics of austenitic stainless steel sheet alloys under warm hydroforming conditions

    Microsoft Academic Search

    Muammer Koç; Sasawat Mahabunphachai; Eren Billur

    2011-01-01

    Stainless steel sheet alloys have been increasingly used in heating, ventilating, and air conditioning; appliance; sanitary\\u000a and medical devices; as well as several structural and transportation applications, due to their high strength-to-weight ratio,\\u000a corrosion resistance, biomedical compatibility, and esthetic appearance. Among various stainless steel alloys, austenitic\\u000a stainless steels are the most commonly used type. Due to the forming limitations into

  18. Cari Kitahara, Ph.D.

    Cancer.gov

    Dr. Kitahara earned her Ph.D. in cancer epidemiology from the Johns Hopkins Bloomberg School of Public Health. She joined the Radiation Epidemiology Branch in 2008 as a predoctoral fellow and became a research fellow in 2011. In 2015, she was appointed to the position of tenure-track investigator.

  19. General and Localized corrosion of Austenitic and Borated Stainless Steels in Simulated Concentrated Ground Waters

    SciTech Connect

    D. Fix; J. Estill; L. Wong; R. Rebak

    2004-05-28

    Boron containing stainless steels are used in the nuclear industry for applications such as spent fuel storage, control rods and shielding. It was of interest to compare the corrosion resistance of three borated stainless steels with standard austenitic alloy materials such as type 304 and 316 stainless steels. Tests were conducted in three simulated concentrated ground waters at 90 C. Results show that the borated stainless were less resistant to corrosion than the witness austenitic materials. An acidic concentrated ground water was more aggressive than an alkaline concentrated ground water.

  20. The pH of antiseptic cleansers

    PubMed Central

    Kulthanan, Kanokvalai; Varothai, Supenya; Nuchkull, Piyavadee

    2014-01-01

    Background Daily bathing with antiseptic cleansers are proposed by some physicians as an adjunctive management of atopic dermatitis (AD). As atopic skin is sensitive, selection of cleansing products becomes a topic of concern. Objective Our purpose is to evaluate the pH of various antiseptic body cleansers to give an overview for recommendation to patients with AD. Methods Commonly bar and liquid cleansers consisted of antiseptic agents were measured for pH using pH meter and pH-indicator strips. For comparison, mild cleansers and general body cleansers were also measured. Results All cleansing bars had pH 9.8-11.3 except syndet bar that had neutral pH. For liquid cleansers, three cleansing agents had pH close to pH of normal skin, one of antiseptic cleansers, one of mild cleansers and another one of general cleansers. The rest of antiseptic cleansers had pH 8.9-9.6 while mild cleansers had pH 6.9-7.5. Syndet liquid had pH 7 and general liquid cleansers had pH 9.6. Conclusion The pH of cleanser depends on composition of that cleanser. Adding antiseptic agents are not the only factor determining variation of pH. Moreover, benefit of antiseptic properties should be considered especially in cases of infected skin lesions in the selection of proper cleansers for patients with AD. PMID:24527408

  1. Effect of glucose and pH on the microbial flora and sensory characteristics of normal and dark, firm, dry beef steaks displayed in polyvinyl chloride film and in vacuum packages 

    E-print Network

    Chesser, Linda Kay

    1982-01-01

    steaks with and without added glucose displayed for 0-6 days in PVC film at 2 C (Trial 3) Display Time (Days) Added Glucose pH (pg/g meat) APCa Percenta e Distribution of Microbial Flora (log10/cm ) Lac B. t Mic Ps Ac 5. 25 1. 75 58. 8 23. 5 17. 7... film at 2 C (Trial 1) Display Time (Days) Added Acid pH APC Percenta e Distribution of Microbial Flora (log10/cm ) B. t Mic Ps Y 0 None 6. 00 &1. 00 3 None 6. 00 2. 29 10. 3 100. 0 89. 7 3 Citrate 6. 01 2. 53 2. 9 2. 0 46. 1 49. 0 3 Citrate...

  2. Stella Koutros, Ph.D.

    Cancer.gov

    Dr. Koutros received her M.P.H. and Ph.D. in epidemiology from Yale University. She completed her doctoral work through the Yale-NCI partnership training program in cancer epidemiology, conducting research in the Occupational and Environmental Epidemiology Branch (OEEB). In 2008, upon completion of her doctorate she became a fellow in OEEB; she was appointed to the position of tenure-track investigator in 2015.

  3. Stress Corrosion Cracking Behavior of Cast Stainless Steels

    SciTech Connect

    Teysseyre, Sebastien [University of Michigan; Busby, Jeremy T [ORNL; Was, Gary [University of Michigan

    2009-01-01

    Casting of austenitic stainless steels offers the possibility of directly producing large and/or relatively complex structures, such as the first wall shield modules or the diverter cassette for the ITER fusion reactor. Casting offers major cost savings when compared to fabrication via welding of quarter modules machined from large forgings. However, the strength properties of such cast components are typically considered inferior to those of conventionally forged and annealed components. To improve and validate cast stainless steel as a substitute for wrought stainless steel, a development and testing program was initiated, utilizing nitrogen and manganese additions to promote improved performance. This paper focuses on the response of the first set of developmental alloys to neutron-irradiation and susceptibility to stress corrosion cracking. These cast materials may also have applications for different components in light water reactors. Results showed that all steels exhibited irradiation-induced hardening and a corresponding drop in ductility, as expected, although there is still considerable ductility in the irradiated samples. The cast steels all exhibited reduced hardening in comparison to a wrought reference steels, which may be related to a larger grain size. Higher nitrogen contents did not negatively influence irradiation performance. Regarding stress corrosion cracking susceptibility, the large difference in grain size limits the comparison between wrought and cast materials, and inclusions in a reference and archive cast alloy tests complicate analysis of these samples. Results suggest that the irradiated archive heat was more susceptible to cracking than the modified alloys, which may be related to the more complex microstructure. Further, the results suggest that the modified cast steel is at least as SCC resistant as wrought 316LN. The beneficial effect of nitrogen on the mechanical properties of the alloys remains after irradiation and is not detrimental to SCC resistance.

  4. Systems design of high-performance stainless steels

    NASA Astrophysics Data System (ADS)

    Campbell, Carelyn Elizabeth

    A systems approach has been applied to the design of high performance stainless steels. Quantitative property objectives were addressed integrating processing/structure/property relations with mechanistic models. Martensitic transformation behavior was described using the Olson-Cohen model for heterogeneous nucleation and the Ghosh-Olson solid-solution strengthening model for interfacial mobility, and incorporating an improved description of Fe-Co-Cr thermodynamic interaction. Coherent Msb2C precipitation in a BCC matrix was described, taking into account initial paraequilibrium with cementite. Using available SANS data, a composition dependent strain energy was calibrated and a composition independent interfacial energy was evaluated to predict the critical particle size versus the fraction of the reaction completed as input to strengthening theory. Multicomponent Pourbaix diagrams provided an effective tool for evaluating oxide stability; constrained equilibrium calculations correlated oxide stability to Cr enrichment in the oxide film to allow more efficient use of alloy Cr content. Multicomponent solidification simulations provided composition constraints to improve castability. Using the Thermo-Calc and DICTRA software packages, the models were integrated to design a carburizing, secondary-hardening martensitic stainless steel. Initial characterization of the prototype showed good agreement with the design models and achievement of the desired property objectives. Prototype evaluation confirmed the predicted martensitic transformation temperature and the desired carburizing response, achieving a case hardness of Rsb{c} 64 in the secondary-hardened condition without case primary carbides. Decarburization experiments suggest that the design core toughness objective (Ksb{IC} = 65 MPasurdm) can be achieved by reducing the core carbon level to 0.05 weight percent. To achieve the core toughness objective at high core strength levels requires further analysis of an observed intergranular fracture mechanism. Anodic polarization curves and salt-fog testing demonstrated superior corrosion resistance to 440C stainless steel with significantly reduced Cr content.

  5. Osteogenic ability of Cu-bearing stainless steel.

    PubMed

    Ren, Ling; Wong, Hoi Man; Yan, Chun Hoi; Yeung, Kelvin W K; Yang, Ke

    2014-11-23

    A newly developed copper-bearing stainless steel (Cu-SS) by directly immobilizing proper amount of Cu into a medical stainless steel (317L SS) during the metallurgical process could enable continuous release of trace amount of Cu(2+) ions, which play the key role to offer the multi-biofunctions of the stainless steel, including the osteogenic ability in the present study. The results of in vitro experiments clearly demonstrated that Cu(2+) ions from Cu-SS could promote the osteogenic differentiation by stimulating the Alkaline phosphatase enzyme activity and the osteogenic gene expressions (Col1a1, Opn, and Runx2), and enhancing the adhesion and proliferation of osteoblasts cultured on its surface. The in vivo test further proved that more new bone tissue formed around the Cu-SS implant with more stable bone-to-implant contact in comparison with the 317L SS. In addition, Cu-SS showed satisfied biocompatibility according to the results of in vitro cytotoxicity and in vivo histocompatibility, and its daily released amount of Cu(2+) ions in physiological saline solution was at trace level of ppb order (1.4 ppb/cm(2) ), which is rather safe to human health. Apart from these results, it was also found that Cu-SS could inhibit the happening of inflammation with lower TNF-? expression in the bone tissue post implantation compared with 317L SS. In addition to good biocompatibility, the overall findings demonstrated that the Cu-SS possessed obvious ability of promoting osteogenesis, indicating a unique application advantage in orthopedics. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2014. PMID:25418073

  6. Aging and Embrittlement of High Fluence Stainless Steels

    SciTech Connect

    Was, gary; Jiao, Zhijie; der ven, Anton Van; Bruemmer, Stephen; Edwards, Dan

    2012-12-31

    Irradiation of austenitic stainless steels results in the formation of dislocation loops, stacking fault tetrahedral, Ni-Si clusters and radiation-induced segregation (RIS). Of these features, it is the formation of precipitates which is most likely to impact the mechanical integrity at high dose. Unlike dislocation loops and RIS, precipitates exhibit an incubation period that can extend from 10 to 46 dpa, above which the cluster composition changes and a separate phase, (G-phase) forms. Both neutron and heavy ion irradiation showed that these clusters develop slowly and continue to evolve beyond 100 dpa. Overall, this work shows that the irradiated microstructure features produced by heavy ion irradiation are remarkably comparable in nature to those produced by neutron irradiation at much lower dose rates. The use of a temperature shift to account for the higher damage rate in heavy ion irradiation results in a fairly good match in the dislocation loop microstructure and the precipitate microstructure in austenitic stainless steels. Both irradiations also show segregation of the same elements and in the same directions, but to achieve comparable magnitudes, heavy ion irradiation must be conducted at a much higher temperature than that which produces a match with loops and precipitates. First-principles modeling has confirmed that the formation of Ni-Si precipitates under irradiation is likely caused by supersaturation of solute to defect sinks caused by highly correlated diffusion of Ni and Si. Thus, the formation and evolution of Ni-Si precipitates at high dose in austenitic stainless steels containing Si is inevitable.

  7. Laser Welding of Large Scale Stainless Steel Aircraft Structures

    NASA Astrophysics Data System (ADS)

    Reitemeyer, D.; Schultz, V.; Syassen, F.; Seefeld, T.; Vollertsen, F.

    In this paper a welding process for large scale stainless steel structures is presented. The process was developed according to the requirements of an aircraft application. Therefore, stringers are welded on a skin sheet in a t-joint configuration. The 0.6 mm thickness parts are welded with a thin disc laser, seam length up to 1920 mm are demonstrated. The welding process causes angular distortions of the skin sheet which are compensated by a subsequent laser straightening process. Based on a model straightening process parameters matching the induced welding distortion are predicted. The process combination is successfully applied to stringer stiffened specimens.

  8. Low cycle fatigue behavior of aluminum/stainless steel composites

    NASA Technical Reports Server (NTRS)

    Bhagat, R. B.

    1983-01-01

    Composites consisting of an aluminum matrix reinforced with various volume fractions of stainless steel wire were fabricated by hot die pressing under various conditions of temperature, time, and pressure. The composites were tested in plane bending to complete fracture under cycle loading, and the results were analyzed on a computer to obtain a statistically valid mathematical relationship between the low-cycle fatigue life and the fiber volume fraction of the composite. The fractured surfaces of the composites were examined by scanning electron microscopy to identify the characteristic features of fatigue damage. Fatigue damage mechanisms are proposed and discussed.

  9. Evaluation of tantalum 316 stainless steel transition joints

    NASA Technical Reports Server (NTRS)

    Stoner, D. R.

    1972-01-01

    Tubular transition joints providing a metallurgically bonded connection between tantalum and 316 stainless steel pipe sections were comparatively evaluated for durability under thermal cycling conditions approximating the operation of a SNAP-8 mercury boiler. Both coextruded and vacuum brazed transition joints of 50mm (2 inch) diameter were tested by thermal cycling 100 times between 730 C and 120 C(1350 F and 250 F) in a high vacuum environment. The twelve evaluated transition joints survived the full test sequence without developing leaks, although liquid penetrant bond line indications eventually developed in all specimens. The brazed transition joints exhibited the best dimensional stability and bond line durability.

  10. Ferritic-austenitic solidification mode in austenitic stainless steel welds

    Microsoft Academic Search

    N. Suutala; T. Takalo; T. Moisio

    1980-01-01

    The macro-and microstructures of about fifty different stainless welds of the AISI\\/ AWS 300 series are analyzed. The results\\u000a indicate that under conditions corresponding to a typical shielded metal arc (SMA) welding the welds with a ratio in the range\\u000a 1.48?Cr\\u000a eq\\u000a \\/Ni\\u000a eq\\u000a ?1.95, where Ni\\u000a eq\\u000a and Cr\\u000a eq\\u000a are the nickel and chromium equivalents on the Schaeffler

  11. Carbon, nitrogen, and oxygen ion implantation of stainless steel

    SciTech Connect

    Rej, D.J. [Los Alamos National Lab., NM (United States); Gavrilov, N.V.; Emlin, D. [Inst. of Electrophysics, Ekaterinburg (Russia)] [and others

    1995-12-31

    Ion implantation experiments of C, N, and O into stainless steel have been performed, with beam-line and plasma source ion implantation methods. Acceleration voltages were varied between 27 and 50 kV, with pulsed ion current densities between 1 and 10 mA/cm{sup 2}. Implanted doses ranged from 0.5 to 3 {times} 10{sup 18}cm{sup -2}, while workpiece temperatures were maintained between 25 and 800 C. Implant concentration profiles, microstructure, and surface mechanical properties of the implanted materials are reported.

  12. Glow Discharge Plasma Nitriding of AISI 304 Stainless Steel

    NASA Astrophysics Data System (ADS)

    Qayyum, A.; Naveed, M. A.; Zeb, S.; Murtaza, G.; Zakaullah, M.

    2007-08-01

    Glow discharge plasma nitriding of AISI 304 austenitic stainless steel has been carried out for different processing time under optimum discharge conditions established by spectroscopic analysis. The treated samples were analysed by X-ray diffraction (XRD) to explore the changes induced in the crystallographic structure. The XRD pattern confirmed the formation of an expanded austenite phase (?N) owing to incorporation of nitrogen as an interstitial solid solution in the iron lattice. A Vickers microhardness tester was used to evaluate the surface hardness as a function of indentation depth (?m). The results showed clear evidence of surface changes with substantial increase in surface hardness.

  13. Ion-nitriding induced plastic deformation in austenitic stainless steel

    NASA Astrophysics Data System (ADS)

    Grigull, S.; Parascandola, S.

    2000-12-01

    Lattice parameter measurements in ion-nitrided surface layers of austenitic stainless steel have been performed using x-ray microbeam diffraction on samples with different nitrogen contents as a function of depth and grain orientation, respectively. The lattice expansion observed in the layers as a result of nitriding is anisotropic due to the presence of elastic strains, but the austenite (fcc) structure is largely retained. Parallel to the layer-substrate interface the expanded lattice is highly relaxed which is, along with significant changes in the surface morphology, indicative of plastic deformation in the nitrided zone.

  14. Compatibility of stainless steel with Pb-17 AT. % Li

    SciTech Connect

    Tortorelli, P.F.; DeVan, J.H.

    1982-01-01

    The corrosion of type 316 stainless steel and Sandvik HT9 by static Pb-17 at. % Li between 300 and 500/sup 0/C was studied. The resulting weight losses were significantly greater than those of these steels in lithium. The corrosive attack was very uniform, and the room-temperature tensile properties of the steels were unaffected by the exposure. The application of molten Pb-17 at. % Li as a tritium-breeding fluid in conjunction with ferrous alloys in a fusion reactor may be limited to 400/sup 0/C or below.

  15. Apparatus and process for ultrasonic seam welding stainless steel foils

    DOEpatents

    Leigh, Richard W. (New York, NY)

    1992-01-01

    An ultrasonic seam welding apparatus having a head which is rotated to form contact, preferably rolling contact, between a metallurgically inert coated surface of the head and an outside foil of a plurality of layered foils or work materials. The head is vibrated at an ultrasonic frequency, preferably along a longitudinal axis of the head. The head is constructed to transmit vibration through a contacting surface of the head into each of the layered foils. The contacting surface of the head is preferably coated with aluminum oxide to prevent the head from becoming welded to layered stainless steel foils.

  16. Laser-induced color marking of stainless steel

    NASA Astrophysics Data System (ADS)

    Antonczak, Arkadiusz J.; Nowak, Maciej; Koziol, Pawel; Kaczmarek, Pawel R.; Waz, Adam T.; Abramski, Krzysztof M.

    2013-01-01

    This paper presents the analysis of the impact of selected process parameters on the resulting laser color marking. The study was conducted for AISI 304 multipurpose stainless steel using a commercially available industrial fiber laser. It was determined how various process parameters, such as laser power, scanning speed of the laser beam, temperature of the material, location of the sample relative to the focal plane, affect the repeatability of the colors obtained. For objective assessment of color changes, an optical spectrometer and the CIE color difference parameter ?Eab * were used.

  17. Femtosecond laser color marking stainless steel surface with different wavelengths

    NASA Astrophysics Data System (ADS)

    Li, Guoqiang; Li, Jiawen; Hu, Yanlei; Zhang, Chenchu; Li, Xiaohong; Chu, Jiaru; Huang, Wenhao

    2015-03-01

    The femtosecond laser color marking stainless steel surfaces with different incident wavelengths were investigated theoretically and experimentally. It indicates that the spectral regions of the colors firstly increase and then reduce with increasing spatial periods of the ripples induced by laser irradiation. Additionally, the colors are gradually changed from blue to red due to the elongation of the diffracted light wavelengths. As a result, the color effects are distinctly different. This study offers a new controllable parameter to produce diverse colors, which may find a wide range of applications in the laser color marking, art designing and so on.

  18. Controlled powder morphology experiments in megabar 304 stainless steel compaction

    SciTech Connect

    Staudhammer, K.P.; Johnson, K.A.

    1985-01-01

    Experiments with controlled morphology including shape, size, and size distribution were made on 304L stainless steel powders. These experiments involved not only the powder variables but pressure variables of 0.08 to 1.0 Mbar. Also included are measured container strain on the material ranging from 1.5% to 26%. Using a new strain controllable design it was possible to seperate and control, independently, strain and pressure. Results indicate that powder morphology, size distribution, packing density are among the pertinent parameters in predicting compaction of these powders.

  19. Use of duplex stainless steel castings in control valves

    SciTech Connect

    Gossett, J.L. [Fisher Controls International, Inc., Marshalltown, IA (United States)

    1996-07-01

    Duplex stainless steels have enjoyed rapidly increasing popularity in recent years. For numerous reasons the availability of these alloys in the cast form has lagged behind the availability of the wrought form. Commercial demand for control valves in these alloys has driven development of needed information to move into production. A systematic approach was used to develop specifications, suppliers and weld procedures. Corrosion, stress corrosion cracking (SCC), sulfide stress cracking (SSC) and hardness results are also presented for several alloys including; CD3MN (UNS J92205), CD4MCu (UNS J93370) and CD7MCuN (cast UNS S32550).

  20. High Strength Stainless Steel Properties that Affect Resistance Welding

    SciTech Connect

    Kanne, W.R.

    2001-08-01

    This report discusses results of a study on selected high strength stainless steel alloy properties that affect resistance welding. The austenitic alloys A-286, JBK-75 (Modified A-286), 21-6-9, 22-13-5, 316 and 304L were investigated and compared. The former two are age hardenable, and the latter four obtain their strength through work hardening. Properties investigated include corrosion and its relationship to chemical cleaning, the effects of heat treatment on strength and surface condition, and the effect of mechanical properties on strength and weldability.

  1. Oxidation resistant high creep strength austenitic stainless steel

    DOEpatents

    Brady, Michael P.; Pint, Bruce A.; Liu, Chain-Tsuan; Maziasz, Philip J.; Yamamoto, Yukinori; Lu, Zhao P.

    2010-06-29

    An austenitic stainless steel displaying high temperature oxidation and creep resistance has a composition that includes in weight percent 15 to 21 Ni, 10 to 15 Cr, 2 to 3.5 Al, 0.1 to 1 Nb, and 0.05 to 0.15 C, and that is free of or has very low levels of N, Ti and V. The alloy forms an external continuous alumina protective scale to provide a high oxidation resistance at temperatures of 700 to 800.degree. C. and forms NbC nanocarbides and a stable essentially single phase fcc austenitic matrix microstructure to give high strength and high creep resistance at these temperatures.

  2. Sol-gel coatings for chemical protection of stainless steel

    Microsoft Academic Search

    PEDRO DE LIMA NETO; Mohamed Atik; Luis A. Avaca; Michel A. Aegerter

    1994-01-01

    Sol-gel thin coatings of ZrO2, SiO2, 70SiO2-30TiO2 and 88SiO2-12Al2O3 compositions (mole %) have been prepared from sonocatalyzed sols and deposited by dip-coating technique on 316L stainless steel foils. The influence of the coatings on the chemical corrosion of the substrate has been measured through potentiodynamic polarization curves in aqueous 15% H2SO4 solution between 25 and 50°C. The values of the

  3. Weld repair of austenitic stainless steels containing helium

    SciTech Connect

    Kanne, W.R. Jr.; Franco-Ferreira, E.A.; Louthan, M.R. Jr.; Tosten, M.H.

    1990-12-31

    Laboratory studies have shown that a weld overlay technique is a potential method for repair of austenitic stainless steel containing helium from irradiation or from implantation by tritium. An interest in helium embrittlement cracking during welding developed as a result of an extensive program to determine the cause of leaks in repair welds in a nuclear reactor tank. Recent studies have demonstrated the suitability of the overlay technique for welding over stress corrosion cracks in nuclear reactor vessels. This paper summarizes results of overlay weld development on helium-bearing material and emphasizes application of the technique over intergranular cracks. It contains two pages of text and twenty-nine viewgraphs. 2 refs.

  4. Weld repair of austenitic stainless steels containing helium

    SciTech Connect

    Kanne, W.R. Jr.; Franco-Ferreira, E.A.; Louthan, M.R. Jr.; Tosten, M.H.

    1990-01-01

    Laboratory studies have shown that a weld overlay technique is a potential method for repair of austenitic stainless steel containing helium from irradiation or from implantation by tritium. An interest in helium embrittlement cracking during welding developed as a result of an extensive program to determine the cause of leaks in repair welds in a nuclear reactor tank. Recent studies have demonstrated the suitability of the overlay technique for welding over stress corrosion cracks in nuclear reactor vessels. This paper summarizes results of overlay weld development on helium-bearing material and emphasizes application of the technique over intergranular cracks. It contains two pages of text and twenty-nine viewgraphs. 2 refs.

  5. Microstructures of laser deposited 304L austenitic stainless steel

    SciTech Connect

    BROOKS,JOHN A.; HEADLEY,THOMAS J.; ROBINO,CHARLES V.

    2000-05-22

    Laser deposits fabricated from two different compositions of 304L stainless steel powder were characterized to determine the nature of the solidification and solid state transformations. One of the goals of this work was to determine to what extent novel microstructure consisting of single-phase austenite could be achieved with the thermal conditions of the LENS [Laser Engineered Net Shape] process. Although ferrite-free deposits were not obtained, structures with very low ferrite content were achieved. It appeared that, with slight changes in alloy composition, this goal could be met via two different solidification and transformation mechanisms.

  6. General and Localized Corrosion of Borated Stainless Steels

    SciTech Connect

    T.E. Lister; Ronald E. Mizia; A.W. Erickson; T.L. Trowbridge; B. S. Matteson

    2008-03-01

    The Transportation, Aging and Disposal (TAD) canister-based system is being proposed to transport and store spent nuclear fuel at the Monitored Geologic Repository (MGR) located at Yucca Mountain, Nevada. The preliminary design of this system identifies borated stainless steel as the neutron absorber material that will be used to fabricate fuel basket inserts for nuclear criticality control. This paper discusses corrosion test results for verifying the performance of this material manufactured to the requirements of ASTM A887, Grade A, under the expected repository conditions.

  7. The effects of alpha particle irradiation on stainless steel 

    E-print Network

    Shipp, John Douglas

    1999-01-01

    (1000), Pu 239, Pu 240, Am 241 +, deveta(1000), dev Jz, devflux, avgSae(1000) +, avgeta(1000), avg Jz, avgflux, stdSae(1000) +, stdeta(1000), std Jz, stdflux, particle(10), avgparticle, stdparticle, +sumparticle, Elow, Elo(10), devElo, stdElo, sum...THE EFFECTS OF ALPHA PARTICLE IRRADIATION ON STAINLESS STEEL A Thesis by JOHN DOUGLAS SHIPP Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE...

  8. Quantitative evaluation of general corrosion of Type 304 stainless steel in subcritical and

    E-print Network

    Benning, Liane G.

    - sion, such as pitting and stress corrosion cracking. However, potential or current monitoring can onlyQuantitative evaluation of general corrosion of Type 304 stainless steel in subcritical the corrosion rate of Type 304 stainless steel (SS) in subcritical and supercritical environments. The EN

  9. Surface Alloying of Nitrogen to Improve Corrosion Resistance of Steels and Stainless Steels

    Microsoft Academic Search

    U. Kamachi Mudali; H. S. Khatak; Baldev Raj; M. Uhlemann

    2004-01-01

    It is well known that the addition of nitrogen to steels and stainless steels enhances the passivity and localized corrosion resistance, in addition to improving the mechanical properties. Selective alloying of surfaces of steels and stainless steels with nitrogen could also enhance the corrosion resistance and improve the mechanical properties without affecting the bulk properties. Techniques like ion implantation, laser

  10. Accepted Manuscript Effect of Corrosion on the High Cycle Fatigue Strength of Martensitic Stainless

    E-print Network

    Paris-Sud XI, Université de

    Ra: Arithmetic surface roughness Introduction Currently, engineering departments are awareAccepted Manuscript Effect of Corrosion on the High Cycle Fatigue Strength of Martensitic Stainless of Corrosion on the High Cycle Fatigue Strength of Martensitic Stainless Steel X12CrNiMoV12-3, International

  11. Microstructures and formability of type 304 stainless steel in deep drawing

    Microsoft Academic Search

    J. S. Chang; S. S. Chou

    1994-01-01

    On the structural inhomogeneity of austenitic stainless steels, investigations revealed that microstructures of deformation twins, shear band and martensites were generated during individual plastic deformation tests. They are of enough significant engineering importance in affecting the mechanical properties and the ductility and formability. The rapid rate of strain-induced martensitic transformation in type 304 stainless steel causes low ductility and leads

  12. On the resistance spot weldability of galvanized interstitial free steel sheets with austenitic stainless steel sheets

    Microsoft Academic Search

    Murat Vural; Ahmet Akkus

    2004-01-01

    This paper presents an experimental study on the resistance spot weldability of galvanized Interstitial Free (cold formable) steel sheets with austenitic stainless steel sheets. Galvanized IF and austenitic stainless steel sheets were joined by using resistance spot welding as lap joint. Firstly, the variation of the Nugget diameter according to welding current was investigated. Tensile-shear tests were applied to the

  13. EVALUATIONS OF EFFECT OF UOâ ON THE CORE STRENGTH OF STAINLESS STEEL FUEL ELEMENTS (TASK 7306)

    Microsoft Academic Search

    Funston

    1952-01-01

    A test procedure was established for evaluating the core strength of ; stainless steel fuel elements at temperatures to 1800 deg F. This evaluation, ; known as a transverse rupture test, measures the short time tensile stress ; required to rupture a specimen in a plane parallel to the surface of the sheet. ; The strength of commercial 309 stainless

  14. Stress corrosion behavior of stainless steel welds in high temperature water containing chlorides

    Microsoft Academic Search

    R. Viswanathan; J. I. Nurminen; R. G. Aspden

    1979-01-01

    The effects of delta ferrite, carbon content and postweld heat treatment on the stress corrosion susceptibility of AISI Types 308, 309, and 316 stainless steel surfacing welds in high temperature water have been investigated. For each type of stainless steel, the initial ferrite level was controlled at three predetermined levels in the range 1 to 10%, and the carbon content

  15. Nasal cell micronuclei, cytology and clinical symptoms in stainless steel production workers exposed to chromium

    Microsoft Academic Search

    Markku Huvinen; Antti Makitie; Hilkka Jarventaus; Henrik Wolff; Tuula Stjernvall; Arja Hovi; Ari Hirvonen; Riikka Ranta; Markku Nurminen; Hannu Norppa

    2002-01-01

    The objective of the present study was to determine whether workers in stainless steel production with low exposure to various forms of chromium show an increase in micro- nucleated nasal cells or an excess of nasal symptoms or disease. Altogether, 48 workers employed in a stainless steel production chain were studied, 29 of them in the steel melting shop with

  16. Effect of weld thermal cycle, stress and helium content on helium bubble formation in stainless steels

    Microsoft Academic Search

    S. Kawano; F. Kano; C. Kinoshita; A. Hasegawa; K. Abe

    2002-01-01

    Helium bubble structure was examined on a helium-implanted stainless steel after applying thermal and stress cycle using a weld thermal and stress cycle simulator. Helium ions were implanted on Type 304 stainless steels up to 200 appm uniformly to a depth of 3.5 ?m. The specimens were heated at various temperatures between 1073 and 1473 K for 2 s in

  17. Effect of d-ferrite on impact properties of supermartensitic stainless steel

    E-print Network

    Cambridge, University of

    affects the impact properties of the HAZ. Charpy impact testing has been chosen to evaluate the impactEffect of d-ferrite on impact properties of supermartensitic stainless steel heat affected zones D of the presence of non-equilibrium d-ferrite on the impact properties of a supermartensitic stainless steel

  18. A comparison of thermal outgassing rates of aluminum alloy and stainless steel vacuum chambers

    Microsoft Academic Search

    J. R. Chen; C. H. Lee; Y. C. Liu

    1988-01-01

    Thermal outgassing rates from 6063 aluminum alloy and 304 stainless steel vacuum chambers are compared. The outgassing rates after the treatments of filling the chamber with water, filling the chamber with N2 gas and after different times of air exposure are measured. Before bakeout, the outgassing rate from aluminum alloy is higher than that from stainless steel. After bakeout, however,

  19. Submerged arc welding of stainless steel and the challenge from the laser welding process

    Microsoft Academic Search

    N. A McPherson; K Chi; T. N Baker

    2003-01-01

    The welding of austenitic and duplex stainless steels has been reassessed by questioning traditional requirements of the weld metal and\\/or the heat affected zone (HAZ). The use of high dilution submerged arc welding of austenitic and duplex stainless steels has been shown to produce acceptable properties, despite the high heat input used in some instances. Corrosion characteristics have been established

  20. The Effect of Cutting Parameters on Surface Roughness when Diamond Cutting Stainless Steel

    Microsoft Academic Search

    Zhi-min Zhou; Yuan-liang Zhang; Xiao-yan Li; Shao-jun Hong; Zhi-hui Xia

    2009-01-01

    When using diamond tool to cut the special stainless steel, the influence of cutting parameters on machining surface roughness is so great. Experiments of cutting special stainless steel by ultrasonic vibration were taken to develop the law that cutting parameters influence on surface roughness of the work piece. The relation curves between cutting parameters and the work piece surface roughness

  1. Some microstructures developed in 303 stainless steel which has been shock loaded to the megabar range

    Microsoft Academic Search

    D. J. Sandstrom; T. I. Jones

    1977-01-01

    A solid sphere of 303 stainless steel was subjected to a multi-megabar shock pressure in a spherically convergent high explosive system. The recovered stainless steel wall was subjected to a metallurgical examination to determine the microstructural features developed in the ball. The most recent examination was prompted by the desire to determine whether the solidification rates developed in the ball

  2. Photoactive and antibacterial TiO 2 thin films on stainless steel

    Microsoft Academic Search

    P. Evans; D. W. Sheel

    2007-01-01

    This paper describes an innovative method to achieve highly photoactive and antibacterial titania thin films on stainless steel by a novel combination of flame-assisted CVD (FACVD) – to deposit silica, and thermal APCVD – to deposit titania. We compare the chemical and structural characteristics, and photocatalytic activities of thin films of titania deposited onto stainless steel using APCVD from two

  3. SINGLE-PHASE SOLIDIFICATION DURING RAPID-RESOLIDIFICATION OF STAINLESS STEEL ALLOYS

    E-print Network

    Eagar, Thomas W.

    SINGLE-PHASE SOLIDIFICATION DURING RAPID- RESOLIDIFICATION OF STAINLESS STEEL ALLOYS ABSTRACT J. W The relative fractions of ferrite and austenite that solidify from a stainless steel (SS) alloy oepend on the alloy composition and the solidification rate. Many common SS-alloy microstructures consist of a mixture

  4. Electrochemical and XPS studies of AISI 316L stainless steel after electropolishing in a magnetic field

    Microsoft Academic Search

    T. Hryniewicz; K. Rokosz; R. Rokicki

    2008-01-01

    The thermodynamic stability and corrosion resistance of surface oxide layer are the most important features of stainless steels. Electrochemical polishing (EP) is the most extensively used surface technology for austenitic stainless steels. We have modified this surface technology by introducing a magnetic field to the system. With this new process called the magnetoelectropolishing (MEP) we can improve metal surface properties

  5. An overview for the utilization of wastes from stainless steel industries

    Microsoft Academic Search

    Zhang Huaiwei; Hong Xin

    2011-01-01

    Significant quantities of wastes are generated as the waste materials or byproducts every day from stainless steel processes. According to the origins and characteristics, the stainless steel wastes can be mainly classified into two categories, slags and dusts. They usually contained considerable quantities of valuable metals and materials. This paper summarized and analyzed the generation, composition, characteristics and the leaching

  6. Quantitative metallographic method for determining delta ferrite content in austenitic stainless steels. Final report

    Microsoft Academic Search

    Pressly

    1986-01-01

    Delta ferrite is a magnetic form of iron and has a body centered cubic crystal structure. It is often present as a nonequilibrium phase in austenitic stainless steel welds, castings, and wrought materials. The ferrite content of austenitic stainless steel can directly affect its properties, especially weldability and formability. Therefore, it is highly desirable to be able to predict and\\/or

  7. Estimation of individual dust exposure by magnetopneumography in stainless steel production

    Microsoft Academic Search

    Markku Huvinen; Leo Oksanen; Kalevi Kalliomäki; Pirkko-Liisa Kalliomäki; Markku Moilanen

    1997-01-01

    The objectives of the study were to measure the magnetic dust lung burden of workers in stainless steel production by magnetopneumography (MPG) and to investigate the relationship of the results with air-borne concentrations of dust, total and hexavalent chromium as well as urinary excretion of chromium. There were 128 workers from the chromite mine, sintering plant, ferrochrome smelter, stainless steel

  8. Arc furnace recycling of chromium--nickel from stainless steel wastes

    Microsoft Academic Search

    P. G. Barnard; W. M. Dressel; M. M. Fine

    1977-01-01

    Losses of alloying metals in furnace flue dusts, grinding swarfs, and mill scale produced during the manufacture of stainless steel are substantial. About 25 million lb Cr, 8.7 million lb Ni, and 150,000 lb Mo and other critical metals can be made available annually for recycling by a process developed by the Bureau of Mines. Stainless steel wastes pelletized with

  9. 75 FR 76025 - Stainless Steel Butt-Weld Pipe Fittings From Japan, Korea, and Taiwan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-07

    ...731-TA-376 and 563-564 (Third Review)] Stainless Steel Butt-Weld Pipe Fittings From Japan, Korea, and Taiwan AGENCY...revocation of the antidumping duty orders on stainless steel butt-weld pipe fittings from Japan, Korea, and Taiwan would...

  10. Difference in metallic wear distribution released from commercially pure titanium compared with stainless steel plates

    Microsoft Academic Search

    G. D. Krischak; F. Gebhard; W. Mohr; V. Krivan; A. Ignatius; A. Beck; N. J. Wachter; P. Reuter; M. Arand; L. Kinzl; L. E. Claes

    2004-01-01

    Introduction Stainless steel and commercially pure titanium are widely used materials in orthopedic implants. However, it is still being controversially discussed whether there are significant differences in tissue reaction and metallic release, which should result in a recommendation for preferred use in clinical practice. Materials and methods A comparative study was performed using 14 stainless steel and 8 commercially pure

  11. Copper precipitation in cobalt-alloyed precipitation-hardened stainless steel

    E-print Network

    Medvedeva, Julia E.

    Copper precipitation in cobalt-alloyed precipitation-hardened stainless steel Arpana S. Murthy online 1 March 2012 The influence of cobalt addition on precipitation of copper in a high-strength stainless steel was investigated using three-dimen- sional atom probe tomography. A decrease in copper

  12. Quantitative evaluation of material degradation of thermally aged duplex stainless steels using chemical immersion test

    Microsoft Academic Search

    Y. S. Yi; T. Shoji

    1996-01-01

    In order to develop a non-destructive evaluation technique for detection of thermal aging embrittlement of duplex stainless steels, corrosion tests on unaged and aged specimens of cast duplex stainless steels were performed in 5 wt% HCl solution. After the immersion test, the dissolution rate of specimens was obtained by a dissolved depth measurement with an AFM. In the measurements of

  13. Pitting corrosion and crevice corrosion behaviors of high nitrogen austenitic stainless steels

    Microsoft Academic Search

    Hua-bing Li; Zhou-hua Jiang; Yan Yang; Yang Cao; Zu-rui Zhang

    2009-01-01

    Pitting corrosion and crevice corrosion behaviors of high nitrogen austenitic stainless steels (HNSS) were investigated by electrochemical and immersion testing methods in chloride solution, respectively. The chemical constitution and composition in the depth of passive films formed on HNSS were analyzed by X-ray photoelectron spectrum (XPS). HNSS has excellent pitting and crevice corrosion resistance compared to 316L stainless steel. With

  14. Electrochemical corrosion characteristics of type 316 stainless steel in simulated anode environment for PEMFC

    Microsoft Academic Search

    M. C. Li; C. L. Zeng; S. Z. Luo; J. N. Shen; H. C. Lin; C. N. Cao

    2003-01-01

    The corrosion behavior of type 316 stainless steel in simulated anode environment for proton exchange membrane fuel cell (PEMFC), i.e., dilute hydrochloric acid solutions bubbled with pure hydrogen gas at 80°C, was investigated by using electrochemical measurement techniques. The main purpose is to offer some fundamental information for the use of stainless steels as bipolar plate material for PEMFC. Both

  15. Ion nitriding of a superaustenitic stainless steel: Wear and corrosion characterization

    Microsoft Academic Search

    F. A. P. Fernandes; S. C. Heck; R. G. Pereira; C. A. Picon; P. A. P. Nascente; L. C. Casteletti

    2010-01-01

    The superiority of superaustenitic stainless steel (SASS) lies in its good weldability and great resistance to stress corrosion and pitting, because of its higher chromium, molybdenum, and nitrogen contents, when compared to general stainless steels. However, some of its applications are limited by very poor wear behavior. Plasma-nitriding is a very effective treatment for producing wear resistant and hard surface

  16. Thin palladium film formation on shot peening modified porous stainless steel substrates

    Microsoft Academic Search

    Naceur Jemaa; Jun Shu; Serge Kaliaguine; Bernard P. A. Grandjean

    1996-01-01

    The rapid development of catalytic membrane reactors requires materials with a higher permeability and a better mechanical stability than the current thick membranes. Pd-based composite membranes supported on porous stainless steel offer such an alternative. However, commercially available porous stainless steel materials have to be further worked to reduce the surface pore sizes and ensure the formation of thin Pd

  17. Assessment of bacterial biofilm on stainless steel by hyperspectral fluorescence imaging

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hyperspectral fluorescence imaging techniques were investigated for detection of two genera of microbial biofilms on stainless steel material which is commonly used to manufacture food processing equipment. Stainless steel coupons were deposited in nonpathogenic E. coli O157:H7 and Salmonella cultu...

  18. Creation of superhydrophobic stainless steel surfaces by acid treatments and hydrophobic film deposition.

    PubMed

    Li, Lester; Breedveld, Victor; Hess, Dennis W

    2012-09-26

    In this work, we present a method to render stainless steel surfaces superhydrophobic while maintaining their corrosion resistance. Creation of surface roughness on 304 and 316 grade stainless steels was performed using a hydrofluoric acid bath. New insight into the etch process is developed through a detailed analysis of the chemical and physical changes that occur on the stainless steel surfaces. As a result of intergranular corrosion, along with metallic oxide and fluoride redeposition, surface roughness was generated on the nano- and microscales. Differences in alloy composition between 304 and 316 grades of stainless steel led to variations in etch rate and different levels of surface roughness for similar etch times. After fluorocarbon film deposition to lower the surface energy, etched samples of 304 and 316 stainless steel displayed maximum static water contact angles of 159.9 and 146.6°, respectively. However, etching in HF also caused both grades of stainless steel to be susceptible to corrosion. By passivating the HF-etched samples in a nitric acid bath, the corrosion resistant properties of stainless steels were recovered. When a three step process was used, consisting of etching, passivation and fluorocarbon deposition, 304 and 316 stainless steel samples exhibited maximum contact angles of 157.3 and 134.9°, respectively, while maintaining corrosion resistance. PMID:22913317

  19. Plasma-nitrided austenitic stainless steel 316L as bipolar plate for PEMFC

    Microsoft Academic Search

    Rujin Tian; Juncai Sun; Liang Wang

    2006-01-01

    Stainless steel bipolar plates for the polymer electrolyte membrane (PEM) fuel cell offer many advantages over conventional machined graphite. Austenitic stainless steel 316L is a traditional candidate for metal bipolar plates. However, the interfacial ohmic loss across the metallic bipolar plate and membrane electrode assembly due to corrosion increases the overall power output of PEMFC. Plasma nitriding was applied to

  20. Dissimilar welding of AISI 310 austenitic stainless steel to nickel-based alloy Inconel 657

    Microsoft Academic Search

    H. Naffakh; M. Shamanian; F. Ashrafizadeh

    2009-01-01

    The current work was carried out to characterize welding of AISI 310 austenitic stainless steel to Inconel 657 nickel–chromium superalloy. The welds were produced using four types of filler materials; the nickel-based corresponding to Inconel 82, Inconel A, Inconel 617 and 310 austenitic stainless steels. This paper describes the selection of welding consumables for the joint. The comparative evaluation was