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Sample records for a2 tool steel

  1. Automated Steel Cleanliness Analysis Tool (ASCAT)

    SciTech Connect

    Gary Casuccio; Michael Potter; Fred Schwerer; Dr. Richard J. Fruehan; Dr. Scott Story

    2005-12-30

    The objective of this study was to develop the Automated Steel Cleanliness Analysis Tool (ASCATTM) to permit steelmakers to evaluate the quality of the steel through the analysis of individual inclusions. By characterizing individual inclusions, determinations can be made as to the cleanliness of the steel. Understanding the complicating effects of inclusions in the steelmaking process and on the resulting properties of steel allows the steel producer to increase throughput, better control the process, reduce remelts, and improve the quality of the product. The ASCAT (Figure 1) is a steel-smart inclusion analysis tool developed around a customized next-generation computer controlled scanning electron microscopy (NG-CCSEM) hardware platform that permits acquisition of inclusion size and composition data at a rate never before possible in SEM-based instruments. With built-in customized ''intelligent'' software, the inclusion data is automatically sorted into clusters representing different inclusion types to define the characteristics of a particular heat (Figure 2). The ASCAT represents an innovative new tool for the collection of statistically meaningful data on inclusions, and provides a means of understanding the complicated effects of inclusions in the steel making process and on the resulting properties of steel. Research conducted by RJLG with AISI (American Iron and Steel Institute) and SMA (Steel Manufactures of America) members indicates that the ASCAT has application in high-grade bar, sheet, plate, tin products, pipes, SBQ, tire cord, welding rod, and specialty steels and alloys where control of inclusions, whether natural or engineered, are crucial to their specification for a given end-use. Example applications include castability of calcium treated steel; interstitial free (IF) degasser grade slag conditioning practice; tundish clogging and erosion minimization; degasser circulation and optimization; quality assessment/steel cleanliness; slab, billet

  2. Method for machining steel with diamond tools

    DOEpatents

    Casstevens, John M.

    1986-01-01

    The present invention is directed to a method for machining optical quality inishes and contour accuracies of workpieces of carbon-containing metals such as steel with diamond tooling. The wear rate of the diamond tooling is significantly reduced by saturating the atmosphere at the interface of the workpiece and the diamond tool with a gaseous hydrocarbon during the machining operation. The presence of the gaseous hydrocarbon effectively eliminates the deterioration of the diamond tool by inhibiting or preventing the conversion of the diamond carbon to graphite carbon at the point of contact between the cutting tool and the workpiece.

  3. Method for machining steel with diamond tools

    DOEpatents

    Casstevens, J.M.

    1984-01-01

    The present invention is directed to a method for machine optical quality finishes and contour accuracies of workpieces of carbon-containing metals such as steel with diamond tooling. The wear rate of the diamond tooling is significantly reduced by saturating the atmosphere at the interface of the workpiece and the diamond tool with a gaseous hydrocarbon during the machining operation. The presence of the gaseous hydrocarbon effectively eliminates the deterioration of the diamond tool by inhibiting or preventing the conversion of the diamond carbon to graphite carbon at the point of contact between the cutting tool and the workpiece.

  4. 30 CFR 57.7050 - Tool and drill steel racks.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Tool and drill steel racks. 57.7050 Section 57... Rotary Jet Piercing Drilling-Surface and Underground § 57.7050 Tool and drill steel racks. Receptacles or racks shall be provided for drill steel and tools stored or carried on drills....

  5. 30 CFR 57.7050 - Tool and drill steel racks.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Tool and drill steel racks. 57.7050 Section 57... Rotary Jet Piercing Drilling-Surface and Underground § 57.7050 Tool and drill steel racks. Receptacles or racks shall be provided for drill steel and tools stored or carried on drills....

  6. 30 CFR 57.7050 - Tool and drill steel racks.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Tool and drill steel racks. 57.7050 Section 57... Rotary Jet Piercing Drilling-Surface and Underground § 57.7050 Tool and drill steel racks. Receptacles or racks shall be provided for drill steel and tools stored or carried on drills....

  7. 30 CFR 56.7050 - Tool and drill steel racks.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Tool and drill steel racks. 56.7050 Section 56... Jet Piercing Drilling § 56.7050 Tool and drill steel racks. Receptacles or racks shall be provided for drill steel and tools stored or carried on drills....

  8. 30 CFR 56.7050 - Tool and drill steel racks.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Tool and drill steel racks. 56.7050 Section 56... Jet Piercing Drilling § 56.7050 Tool and drill steel racks. Receptacles or racks shall be provided for drill steel and tools stored or carried on drills....

  9. 30 CFR 57.7050 - Tool and drill steel racks.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Tool and drill steel racks. 57.7050 Section 57... Rotary Jet Piercing Drilling-Surface and Underground § 57.7050 Tool and drill steel racks. Receptacles or racks shall be provided for drill steel and tools stored or carried on drills....

  10. 30 CFR 56.7050 - Tool and drill steel racks.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Tool and drill steel racks. 56.7050 Section 56... Jet Piercing Drilling § 56.7050 Tool and drill steel racks. Receptacles or racks shall be provided for drill steel and tools stored or carried on drills....

  11. 30 CFR 56.7050 - Tool and drill steel racks.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Tool and drill steel racks. 56.7050 Section 56... Jet Piercing Drilling § 56.7050 Tool and drill steel racks. Receptacles or racks shall be provided for drill steel and tools stored or carried on drills....

  12. Study of hot hardness characteristics of tool steels

    NASA Technical Reports Server (NTRS)

    Chevalier, J. L.; Dietrich, M. W.; Zaretsky, E. V.

    1972-01-01

    Hardness measurements of tool steel materials in electric furnace at elevated temperatures and low oxygen environment are discussed. Development of equation to predict short term hardness as function of intial room temperature hardness of steel is reported. Types of steel involved in the process are identified.

  13. 30 CFR 57.7050 - Tool and drill steel racks.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Tool and drill steel racks. 57.7050 Section 57... MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface and Underground § 57.7050 Tool and drill steel racks. Receptacles or...

  14. 30 CFR 56.7050 - Tool and drill steel racks.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Tool and drill steel racks. 56.7050 Section 56... MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7050 Tool and drill steel racks. Receptacles or racks shall be provided for...

  15. Experimental and Theoretical Investigations of Hot Isostatically Pressed-Produced Stainless Steel/High Alloy Tool Steel Compound Materials

    NASA Astrophysics Data System (ADS)

    Lindwall, Greta; Flyg, Jesper; Frisk, Karin; Sandberg, Odd

    2011-05-01

    Consolidation of tool steel powders and simultaneous joining to a stainless 316L steel are performed by hot isostatic pressing (HIP). Two tool steel grades are considered: a high vanadium alloyed carbon tool steel, and a high vanadium and chromium alloyed nitrogen tool steel. The boundary layer arising during diffusion bonding is in focus and, in particular, the diffusion of carbon and nitrogen over the joint. Measurements of the elemental concentration profiles and corrosion tests by the double loop-electrochemical potentiokinetic reactivation (DL-EPR) method are performed. Comparative calculations with the DICTRA software are performed and are found to be in agreement with the experimental results. It is found that the carbon tool steel grade has a more critical influence on the corrosion resistance of the stainless 316L steel in comparison to the nitrogen tool steel grade.

  16. Tool Steel Heat Treatment Optimization Using Neural Network Modeling

    NASA Astrophysics Data System (ADS)

    Podgornik, Bojan; Belič, Igor; Leskovšek, Vojteh; Godec, Matjaz

    2016-11-01

    Optimization of tool steel properties and corresponding heat treatment is mainly based on trial and error approach, which requires tremendous experimental work and resources. Therefore, there is a huge need for tools allowing prediction of mechanical properties of tool steels as a function of composition and heat treatment process variables. The aim of the present work was to explore the potential and possibilities of artificial neural network-based modeling to select and optimize vacuum heat treatment conditions depending on the hot work tool steel composition and required properties. In the current case training of the feedforward neural network with error backpropagation training scheme and four layers of neurons (8-20-20-2) scheme was based on the experimentally obtained tempering diagrams for ten different hot work tool steel compositions and at least two austenitizing temperatures. Results show that this type of modeling can be successfully used for detailed and multifunctional analysis of different influential parameters as well as to optimize heat treatment process of hot work tool steels depending on the composition. In terms of composition, V was found as the most beneficial alloying element increasing hardness and fracture toughness of hot work tool steel; Si, Mn, and Cr increase hardness but lead to reduced fracture toughness, while Mo has the opposite effect. Optimum concentration providing high KIc/HRC ratios would include 0.75 pct Si, 0.4 pct Mn, 5.1 pct Cr, 1.5 pct Mo, and 0.5 pct V, with the optimum heat treatment performed at lower austenitizing and intermediate tempering temperatures.

  17. 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.

  18. Spark Plasma Co-Sintering of Mechanically Milled Tool Steel and High Speed Steel Powders

    PubMed Central

    Pellizzari, Massimo; Fedrizzi, Anna; Zadra, Mario

    2016-01-01

    Hot work tool steel (AISI H13) and high speed steel (AISI M3:2) powders were successfully co-sintered to produce hybrid tool steels that have properties and microstructures that can be modulated for specific applications. To promote co-sintering, which is made difficult by the various densification kinetics of the two steels, the particle sizes and structures were refined by mechanical milling (MM). Near full density samples (>99.5%) showing very fine and homogeneous microstructure were obtained using spark plasma sintering (SPS). The density of the blends (20, 40, 60, 80 wt % H13) was in agreement with the linear rule of mixtures. Their hardness showed a positive deviation, which could be ascribed to the strengthening effect of the secondary particles altering the stress distribution during indentation. A toughening of the M3:2-rich blends could be explained in view of the crack deviation and crack arrest exerted by the H13 particles. PMID:28773603

  19. Modelling macrosegregation in a 2.45 ton steel ingot

    NASA Astrophysics Data System (ADS)

    Li, J.; Wu, M.; Ludwig, A.; Kharicha, A.

    2012-07-01

    A three phase model for the mixed columnar-equiaxed solidification was proposed by the current authors [Wu and Ludwig 2006 Metall. Mater. Trans. 37A 1613-31]. The main features of the mixed columnar-equiaxed solidification are considered: the growth of the columnar dendrite trunks from the ingot surface, the nucleation and growth of the equiaxed crystals, the sedimentation of the equiaxed crystals, the thermal and solutal buoyancy flow and its interactions with the growing crystals, the solute partitioning at the solid-liquid interface during solidification, the solute transport due to melt convection and equiaxed sedimentation, the mechanical interaction/impingement between columnar and equiaxed crystals and the columnar-to-equiaxed transition (CET). However, due to the model complexity and the limited computational capability the model has not yet applied to the large steel ingots of engineering scale. This paper is going to simulate a 2.45 ton big-end-up industry steel ingot, for which some experimental results were reported [Marburg 1926 Iron Steel Inst. 113 39-176]. Here a simplified binary phase diagram for the steel (Fe-0.45 wt. %C) is considered. Comparison of the modelling results such as as-cast columnar and equiaxed zones, macrosegregation with the experimental results is made. Details about the formation sequence of the distinguished crystal zones and segregation patterns are analyzed.

  20. Evolution of carbides in cold-work tool steels

    SciTech Connect

    Kim, Hoyoung; Kang, Jun-Yun; Son, Dongmin; Lee, Tae-Ho; Cho, Kyung-Mox

    2015-09-15

    This study aimed to present the complete history of carbide evolution in a cold-work tool steel along its full processing route for fabrication and application. A sequence of processes from cast to final hardening heat treatment was conducted on an 8% Cr-steel to reproduce a typical commercial processing route in a small scale. The carbides found at each process step were then identified by electron diffraction with energy dispersive spectroscopy in a scanning or transmission electron microscope. After solidification, MC, M{sub 7}C{sub 3} and M{sub 2}C carbides were identified and the last one dissolved during hot compression at 1180 °C. In a subsequent annealing at 870 °C followed by slow cooling, M{sub 6}C and M{sub 23}C{sub 6} were added, while they were dissolved in the following austenitization at 1030 °C. After the final tempering at 520 °C, fine M{sub 23}C{sub 6} precipitated again, thus the final microstructure was the tempered martensite with MC, M{sub 7}C{sub 3} and M{sub 23}C{sub 6} carbide. The transient M{sub 2}C and M{sub 6}C originated from the segregation of Mo and finally disappeared due to attenuated segregation and the consequent thermodynamic instability. - Highlights: • The full processing route of a cold-work tool steel was simulated in a small scale. • The carbides in the tool steel were identified by chemical–crystallographic analyses. • MC, M{sub 7}C{sub 3}, M{sub 2}C, M{sub 6}C and M{sub 23}C{sub 6} carbides were found during the processing of the steel. • M{sub 2}C and M{sub 6}C finally disappeared due to thermodynamic instability.

  1. Frictional conditions between alloy AA6060 aluminium and tool steel

    SciTech Connect

    Wideroee, Fredrik; Welo, Torgeir

    2011-05-04

    The frictional conditions in the new process of screw extrusion of aluminium have been investigated. The contact behaviour between the aluminum alloy and the tool steel in the extruder is vital for understanding the extrusion process. Using a compressive-rotational method for frictional measurements the conditions for unlubricated sticking friction between aluminum alloy AA6060 and tool steel at different combinations of temperatures and pressures have been investigated. In this method the samples in the form of disks are put under hydrostatic pressure while simultaneously being rotated at one end. Pins made from contrast material have been inserted into the samples to measure the deformation introduced. This approach along with 3D simulations form a method for determining the frictional conditions. The paper describes the test method and the results. It was found that the necessary pressure for sticking to occur between the aluminum AA6060 and the different parts of the extruder is heavily influenced by the temperature.

  2. Frictional conditions between alloy AA6060 aluminium and tool steel

    NASA Astrophysics Data System (ADS)

    Widerøe, Fredrik; Welo, Torgeir

    2011-05-01

    The frictional conditions in the new process of screw extrusion of aluminium have been investigated. The contact behaviour between the aluminum alloy and the tool steel in the extruder is vital for understanding the extrusion process. Using a compressive-rotational method for frictional measurements the conditions for unlubricated sticking friction between aluminum alloy AA6060 and tool steel at different combinations of temperatures and pressures have been investigated. In this method the samples in the form of disks are put under hydrostatic pressure while simultaneously being rotated at one end. Pins made from contrast material have been inserted into the samples to measure the deformation introduced. This approach along with 3D simulations form a method for determining the frictional conditions. The paper describes the test method and the results. It was found that the necessary pressure for sticking to occur between the aluminum AA6060 and the different parts of the extruder is heavily influenced by the temperature.

  3. Cutting tool study: 21-6-9 stainless steel

    SciTech Connect

    McManigle, A.P.

    1992-07-29

    The Rocky Flats Plant conducted a study to test cermet cutting tools by performing machinability studies on War Reserve product under controlled conditions. The purpose of these studies was to determine the most satisfactory tools that optimize tool life, minimize costs, improve reliability and chip control, and increase productivity by performing the operations to specified Accuracies. This study tested three manufacturers' cermet cutting tools and a carbide tool used previously by the Rocky Flats Plant for machining spherical-shaped 21-6-9 stainless steel forgings (Figure 1). The 80-degree diamond inserts were tested by experimenting with various chip-breaker geometries, cutting speeds, feedrates, and cermet grades on the outside contour roughing operation. The cermets tested were manufactured by Kennametal, Valenite, and NTK. The carbide tool ordinarily used for this operation is manufactured by Carboloy. Evaluation of tho tools was conducted by investigating the number of passes per part and parts per insert, tool wear, cutting time, tool life, surface finish, and stem taper. Benefits to be gained from this study were: improved part quality, better chip control, increased tool life and utilization, and greater fabrication productivity. This was to be accomplished by performing the operation to specified accuracies within the scope of the tools tested.

  4. Cutting tool study: 21-6-9 stainless steel

    SciTech Connect

    McManigle, A.P.

    1992-07-29

    The Rocky Flats Plant conducted a study to test cermet cutting tools by performing machinability studies on War Reserve product under controlled conditions. The purpose of these studies was to determine the most satisfactory tools that optimize tool life, minimize costs, improve reliability and chip control, and increase productivity by performing the operations to specified Accuracies. This study tested three manufacturers` cermet cutting tools and a carbide tool used previously by the Rocky Flats Plant for machining spherical-shaped 21-6-9 stainless steel forgings (Figure 1). The 80-degree diamond inserts were tested by experimenting with various chip-breaker geometries, cutting speeds, feedrates, and cermet grades on the outside contour roughing operation. The cermets tested were manufactured by Kennametal, Valenite, and NTK. The carbide tool ordinarily used for this operation is manufactured by Carboloy. Evaluation of tho tools was conducted by investigating the number of passes per part and parts per insert, tool wear, cutting time, tool life, surface finish, and stem taper. Benefits to be gained from this study were: improved part quality, better chip control, increased tool life and utilization, and greater fabrication productivity. This was to be accomplished by performing the operation to specified accuracies within the scope of the tools tested.

  5. Skittle: a 2-dimensional genome visualization tool.

    PubMed

    Seaman, Josiah D; Sanford, John C

    2009-12-30

    It is increasingly evident that there are multiple and overlapping patterns within the genome, and that these patterns contain different types of information--regarding both genome function and genome history. In order to discover additional genomic patterns which may have biological significance, novel strategies are required. To partially address this need, we introduce a new data visualization tool entitled Skittle. This program first creates a 2-dimensional nucleotide display by assigning four colors to the four nucleotides, and then text-wraps to a user adjustable width. This nucleotide display is accompanied by a "repeat map" which comprehensively displays all local repeating units, based upon analysis of all possible local alignments. Skittle includes a smooth-zooming interface which allows the user to analyze genomic patterns at any scale.Skittle is especially useful in identifying and analyzing tandem repeats, including repeats not normally detectable by other methods. However, Skittle is also more generally useful for analysis of any genomic data, allowing users to correlate published annotations and observable visual patterns, and allowing for sequence and construct quality control. Preliminary observations using Skittle reveal intriguing genomic patterns not otherwise obvious, including structured variations inside tandem repeats. The striking visual patterns revealed by Skittle appear to be useful for hypothesis development, and have already led the authors to theorize that imperfect tandem repeats could act as information carriers, and may form tertiary structures within the interphase nucleus.

  6. Modelling of Tool Wear and Residual Stress during Machining of AISI H13 Tool Steel

    SciTech Connect

    Outeiro, Jose C.; Pina, Jose C.; Umbrello, Domenico; Rizzuti, Stefania

    2007-05-17

    Residual stresses can enhance or impair the ability of a component to withstand loading conditions in service (fatigue, creep, stress corrosion cracking, etc.), depending on their nature: compressive or tensile, respectively. This poses enormous problems in structural assembly as this affects the structural integrity of the whole part. In addition, tool wear issues are of critical importance in manufacturing since these affect component quality, tool life and machining cost. Therefore, prediction and control of both tool wear and the residual stresses in machining are absolutely necessary. In this work, a two-dimensional Finite Element model using an implicit Lagrangian formulation with an automatic remeshing was applied to simulate the orthogonal cutting process of AISI H13 tool steel. To validate such model the predicted and experimentally measured chip geometry, cutting forces, temperatures, tool wear and residual stresses on the machined affected layers were compared. The proposed FE model allowed us to investigate the influence of tool geometry, cutting regime parameters and tool wear on residual stress distribution in the machined surface and subsurface of AISI H13 tool steel. The obtained results permit to conclude that in order to reduce the magnitude of surface residual stresses, the cutting speed should be increased, the uncut chip thickness (or feed) should be reduced and machining with honed tools having large cutting edge radii produce better results than chamfered tools. Moreover, increasing tool wear increases the magnitude of surface residual stresses.

  7. Boriding of high carbon high chromium cold work tool steel

    NASA Astrophysics Data System (ADS)

    Muhammad, W.

    2014-06-01

    High-carbon high-chromium cold work tool steels are widely used for blanking and cold forming of punches and dies. It is always advantageous to obtain an increased wear resistant surface to improve life and performance of these steels. In this connection boriding of a high-carbon high-chromium cold work die steel, D3, was conducted in a mixture of 30% B4C, 70% borax at 950 °C for two, four and six hours. Case depth of the borided layer obtained was between 40 to 80 μm. After boriding, the surface hardness achieved was between 1430 to 1544 HV depending upon the process time. X-ray diffraction studies confirmed the formation of a duplex compound layer consisting of FeB and Fe2B. It is generally considered that FeB is undesirable because of its inherent brittleness. Post boriding treatment (homogenization) transformed the compound layer into single-phase layer of Fe2B, while surface hardness decreased to 1345-1430 HV. Pin-on-disc wer test showed that wear resistance of the borided samples was superior as compared to non-borided material and increased with boriding time.

  8. Factors influencing the surface quality of polished tool steels

    NASA Astrophysics Data System (ADS)

    Rebeggiani, S.; Rosén, B.-G.

    2014-09-01

    Today’s demands on surface quality of moulds for injection moulding of plastic components involve no/low defect contents and roughness levels in the nm-range for high gloss applications. Material properties as well as operating conditions influence the mould finish, and thus the final surface of moulded products. This paper focuses on how particle content and different polishing strategies influence final surface qualities of moulds. Visual estimations of polished tool steel samples were combined with non-contact 3D-surface texture analysis in order to correlate traditional assessments to more quantitative methods, and to be able to analyse the surfaces at nanometre-level. It was found that steels with a lower proportion of particles, like carbides and oxides, gave rise to smoother polished surfaces. In a comparative study of polishers from different polishing shops, it was found that while different surface preparation strategies can lead to similar final roughness, similar preparation techniques can produce high-quality surfaces from different steel grades. However, the non-contact 3D-surface texture analysis showed that not all smooth polished surfaces have desirable functional topographies for injection moulding of glossy plastic components.

  9. Influence Of Tool Geometry, Tool Coating And Process Parameters In Thixoextrusion Of Steel

    SciTech Connect

    Knauf, Frederik; Hirt, Gerhard; Immich, Philipp; Bobzin, Kirsten

    2007-04-07

    Thixoextrusion could become one possibility to enlarge the complexity of extruded profiles made of steel. Accordingly semi-solid extrusion experiments of X210CrW12 tool steel using round dies of approximately 15 mm diameter were performed in order to achieve first information concerning possible process windows and process limits. For liquid fractions between 38% and 10%, extrusion press velocities from 10 mm/s to 50 mm/s and dies with novel PVD-coatings no complete solidification during extrusion was achieved. However the collected pieces of the extruded bars showed a fine and evenly distributed globular microstructure.

  10. [Analysis of alloy tool steel using X-ray fluorescence spectrometer].

    PubMed

    Zhou, S; Cai, Y; Huang, Z

    2001-08-01

    This report briefly introduces the analysis of Mn, Cr, V, W, Ti, Nb, Co, Zr, Ni, Mo, S, P, Si and Cu in alloy tool steel with X-ray florescence spectrometer. After being polished with grinding well and being cleaned with ethly alcohol, the test samples can be directly measured, and the results agree well with the standard values of the laboratory standards. The precision of the method (RSD) is in the range of 0.13%-9.56% (n = 8) for all elements except W, Ti, Nb and Zr. The method can be applied to many kinds of steel, such as chrome vanadium steel, manganese steel, die steel, middle-low alloy steel, tool steel. The measure instrument should be rectified with two or three standard samples which the quantity contained is suitable. The standard samples include 1Cr18Ni9Ti, C17Ni2, 25CrMo1V, 30CrMnSiA, 3CrW8V, Gx-8, Cr12MoV, chrome vanadium steel, manganese-boron steel, middle-low alloy steel and other kinds of steel. If there is not conditions to make work curves for all kinds steel separately, sometimes we don't know what kind of steel for one complex sample, the more real way will be to make an overall work curves which contains more kinds of steel as far as possible.

  11. Active wear and failure mechanisms of TiN-coated high speed steel and TiN-coated cemented carbide tools when machining powder metallurgically made stainless steels

    SciTech Connect

    Jiang, L.; Haenninen, H.; Paro, J.; Kauppinen, V.

    1996-09-01

    In this study, active wear and failure mechanisms of both TiN-coated high speed steel and TiN-coated cemented carbide tools when machining stainless steels made by powder metallurgy in low and high cutting speed ranges, respectively, have been investigated. Abrasive wear mechanisms, fatigue-induced failure, and adhesive and diffusion wear mechanisms mainly affected the tool life of TiN-coated high speed steel tools at cutting speeds below 35 m/min, between 35 and 45 m/min, and over 45 m/min, respectively. Additionally, fatigue-induced failure was active at cutting speeds over 45 m/min in the low cutting speed range when machining powder metallurgically made duplex stainless steel 2205 and austenitic stainless steel 316L. In the high cutting speed range, from 100 to 250 m/min, fatigue-induced failure together with diffusion wear mechanism, affected the tool life of TiN-coated cemented carbide tools when machining both 316L and 2205 stainless steels. It was noticed that the tool life of TiN-coated high speed steel tools used in the low cutting speed range when machining 2205 steel was longer than that when machining 316L steel, whereas the tool life of TiN-coated cemented carbide tools used in the high cutting speed range when machining 316L steel was longer than that when machining 2205 steel.

  12. Active wear and failure mechanisms of TiN-Coated high speed steel and tin-coated cemented carbide tools when machining powder metallurgically made stainless steels

    NASA Astrophysics Data System (ADS)

    Jiang, Laizhu; Hänninen, Hannu; Paro, Jukka; Kauppinen, Veijo

    1996-09-01

    In this study, active wear and failure mechanisms of both TiN-coated high speed steel and TiN-coated cemented carbide tools when machining stainless steels made by powder metallurgy in low and high cutting speed ranges, respectively, have been investigated. Abrasive wear mechanisms, fatigue-induced failure, and adhesive and diffusion wear mechanisms mainly affected the tool life of TiN-coated high speed steel tools at cutting speeds below 35 m/min, between 35 and 45 m/min, and over 45 m/min, respectively. Additionally, fatigue-induced failure was active at cutting speeds over 45 m/min in the low cutting speed range when machining powder metallurgically made duplex stainless steel 2205 and austenitic stainless steel 316L. In the high cutting speed range, from 100 to 250 m/min, fatigue-induced failure together with diffusion wear mechanism, affected the tool life of TiN-coated cemented carbide tools when machining both 316L and 2205 stainless steels. It was noticed that the tool life of TiN-coated high speed steel tools used in the low cutting speed range when machining 2205 steel was longer than that when machining 316L steel, whereas the tool life of TiN-coated cemented carbide tools used in the high cutting speed range when machining 316L steel was longer than that when machining 2205 steel.

  13. R-Curve Approach to Describe the Fracture Resistance of Tool Steels

    NASA Astrophysics Data System (ADS)

    Picas, Ingrid; Casellas, Daniel; Llanes, Luis

    2016-06-01

    This work addresses the events involved in the fracture of tool steels, aiming to understand the effect of primary carbides, inclusions, and the metallic matrix on their effective fracture toughness and strength. Microstructurally different steels were investigated. It is found that cracks nucleate on carbides or inclusions at stress values lower than the fracture resistance. It is experimentally evidenced that such cracks exhibit an increasing growth resistance as they progressively extend, i.e., R-curve behavior. Ingot cast steels present a rising R-curve, which implies that the effective toughness developed by small cracks is lower than that determined with long artificial cracks. On the other hand, cracks grow steadily in the powder metallurgy tool steel, yielding as a result a flat R-curve. Accordingly, effective toughness for this material is mostly independent of the crack size. Thus, differences in fracture toughness values measured using short and long cracks must be considered when assessing fracture resistance of tool steels, especially when tool performance is controlled by short cracks. Hence, material selection for tools or development of new steel grades should take into consideration R-curve concepts, in order to avoid unexpected tool failures or to optimize microstructural design of tool steels, respectively.

  14. Failure analysis of a tool-steel torque shaft

    SciTech Connect

    Reagan, J.R.

    1981-01-01

    A low design load drive shaft from an experimental diesel truck engine failed unexpectedly during highway testing. The shaft was driven by a turbine used to deliver power from an experimental exhaust heat recovery system to the engine's crankshaft. During design, fatigue was not considered a major problem because of the low operating cyclic stresses. An independent testing laboratory analyzed the failure by routine metallography. The structure of the hardened S-7 tool steel shaft was banded and the laboratory attributed the failure to fatigue induced by a banded microstructure. NASA was asked to confirm this analysis. Visual examination of the failed shaft plus the knowledge of the torsional load that it carried pointed to a 100% ductile failure with no evidence of fatigue. Scanning electron microscopy confirmed this. Torsional test specimens were produced from pieces of the failed shaft and torsional overload testing produced identical failures to that which had occurred in the truck engine. This pointed to a failure caused by a high overload and although the microstructure was defective it was not the cause of the failure.

  15. Laser surface texturing of tool steel: textured surfaces quality evaluation

    NASA Astrophysics Data System (ADS)

    Šugár, Peter; Šugárová, Jana; Frnčík, Martin

    2016-05-01

    In this experimental investigation the laser surface texturing of tool steel of type 90MnCrV8 has been conducted. The 5-axis highly dynamic laser precision machining centre Lasertec 80 Shape equipped with the nano-second pulsed ytterbium fibre laser and CNC system Siemens 840 D was used. The planar and spherical surfaces first prepared by turning have been textured. The regular array of spherical and ellipsoidal dimples with a different dimensions and different surface density has been created. Laser surface texturing has been realized under different combinations of process parameters: pulse frequency, pulse energy and laser beam scanning speed. The morphological characterization of ablated surfaces has been performed using scanning electron microscopy (SEM) technique. The results show limited possibility of ns pulse fibre laser application to generate different surface structures for tribological modification of metallic materials. These structures were obtained by varying the processing conditions between surface ablation, to surface remelting. In all cases the areas of molten material and re-cast layers were observed on the bottom and walls of the dimples. Beside the influence of laser beam parameters on the machined surface quality during laser machining of regular hemispherical and elipsoidal dimple texture on parabolic and hemispherical surfaces has been studied.

  16. Laser Cladding of Vanadium-Carbide Tool Steels for Die Repair

    NASA Astrophysics Data System (ADS)

    Leunda, J.; Soriano, C.; Sanz, C.; Navas, V. García

    A study of the laser cladding of powder metallurgical tool steels has been carried out. CPM 10 V and Vanadis 4 Extra tool steel powders have been deposited on Vanadis 4 Extra tool steel plates, for repairing purposes, using a Nd:YAG laser. The microstructure of the laser cladding samples was investigated using optical and scanning electron microscopes. The volumetric fraction of retained austenite was evaluated by X-ray diffraction and microhardness profiles were measured. Crack free 700 HV 0.3 cladding tracks were achieved with both materials and coatings show a microstructure of carbides embedded in a martensite plus retained austenite matrix.

  17. Photoemission Electron Microscopy as a Tool for Studying Steel Grains

    NASA Astrophysics Data System (ADS)

    Roese, Peter; Keutner, Christoph; Berges, Ulf; Espeter, Philipp; Westphal, Carsten

    2017-03-01

    Key properties of steel like stability, weldability, or ability for absorbing deformation energy are defined by their grain structure. The knowledge about their micrometer and submicrometer structure is of particular interest for tailor-cut macroscopic steel properties. We report on photoemission electron microscopy studies which in principle yield a higher magnification than comparable optical techniques. A flat surface without any topographic features was obtained by applying a non-etching preparation procedure. PEEM images showed very tiny phase islands embedded within a steel phase matrix. Furthermore, we developed an analysis procedure for PEEM images for dual-phase steels. As a result, it is possible to identify the individual work functions of different steel phases at the surface.

  18. Photoemission Electron Microscopy as a Tool for Studying Steel Grains

    NASA Astrophysics Data System (ADS)

    Roese, Peter; Keutner, Christoph; Berges, Ulf; Espeter, Philipp; Westphal, Carsten

    2017-01-01

    Key properties of steel like stability, weldability, or ability for absorbing deformation energy are defined by their grain structure. The knowledge about their micrometer and submicrometer structure is of particular interest for tailor-cut macroscopic steel properties. We report on photoemission electron microscopy studies which in principle yield a higher magnification than comparable optical techniques. A flat surface without any topographic features was obtained by applying a non-etching preparation procedure. PEEM images showed very tiny phase islands embedded within a steel phase matrix. Furthermore, we developed an analysis procedure for PEEM images for dual-phase steels. As a result, it is possible to identify the individual work functions of different steel phases at the surface.

  19. Microstructural Quantification of Rapidly Solidified Undercooled D2 Tool Steel

    NASA Astrophysics Data System (ADS)

    Valloton, J.; Herlach, D. M.; Henein, H.; Sediako, D.

    2017-10-01

    Rapid solidification of D2 tool steel is investigated experimentally using electromagnetic levitation (EML) under terrestrial and reduced gravity conditions and impulse atomization (IA), a drop tube type of apparatus. IA produces powders 300 to 1400 μm in size. This allows the investigation of a large range of cooling rates ( 100 to 10,000 K/s) with a single experiment. On the other hand, EML allows direct measurements of the thermal history, including primary and eutectic nucleation undercoolings, for samples 6 to 7 mm in diameter. The final microstructures at room temperature consist of retained supersaturated austenite surrounded by eutectic of austenite and M7C3 carbides. Rapid solidification effectively suppresses the formation of ferrite in IA, while a small amount of ferrite is detected in EML samples. High primary phase undercoolings and high cooling rates tend to refine the microstructure, which results in a better dispersion of the eutectic carbides. Evaluation of the cell spacing in EML and IA samples shows that the scale of the final microstructure is mainly governed by coarsening. Electron backscattered diffraction (EBSD) analysis of IA samples reveals that IA powders are polycrystalline, regardless of the solidification conditions. EBSD on EML samples reveals strong differences between the microstructure of droplets solidified on the ground and in microgravity conditions. While the former ones are polycrystalline with many different grains, the EML sample solidified in microgravity shows a strong texture with few much larger grains having twinning relationships. This indicates that fluid flow has a strong influence on grain refinement in this system.

  20. Tool Life Prediction for Ceramic Tools in Intermittent Turning of Hardened Steel Based on Damage Evolution Model

    NASA Astrophysics Data System (ADS)

    Cui, Xiaobin; Zhao, Jun; Zhou, Yonghui; Zheng, Guangming

    2011-07-01

    Al2O3-based ceramic is one of the most widely used materials for tools employed in hardened steel turning applications due to its high hardness, wear resistance, heat resistance and chemical stability. The objective of this work is to predict the lives of Al2O3-(W, Ti)C ceramic tools in intermittent turning of hardened AISI 1045 steel by means of damage evolution model taking into account the mechanical loading and thermal effect in the cutting process. A damage evolution model analyzing the RVE with uniformly distributed interacting cracks is constructed based on micromechanics. The calculated results of the proposed damage evolution model are compared with the lives of two kinds of Al2O3-(W, Ti)C ceramic tools obtained through experiments. It is found that the proposed model can be used to predict the lives of the ceramic cutting tools in intermittent turning operation.

  1. Acoustic Emission Methodology to Evaluate the Fracture Toughness in Heat Treated AISI D2 Tool Steel

    NASA Astrophysics Data System (ADS)

    Mostafavi, Sajad; Fotouhi, Mohamad; Motasemi, Abed; Ahmadi, Mehdi; Sindi, Cevat Teymuri

    2012-10-01

    In this article, fracture toughness behavior of tool steel was investigated using Acoustic Emission (AE) monitoring. Fracture toughness ( K IC) values of a specific tool steel was determined by applying various approaches based on conventional AE parameters, such as Acoustic Emission Cumulative Count (AECC), Acoustic Emission Energy Rate (AEER), and the combination of mechanical characteristics and AE information called sentry function. The critical fracture toughness values during crack propagation were achieved by means of relationship between the integral of the sentry function and cumulative fracture toughness (KICUM). Specimens were selected from AISI D2 cold-work tool steel and were heat treated at four different tempering conditions (300, 450, 525, and 575 °C). The results achieved through AE approaches were then compared with a methodology proposed by compact specimen testing according to ASTM standard E399. It was concluded that AE information was an efficient method to investigate fracture characteristics.

  2. The fracture toughness of borides formed on boronized cold work tool steels

    SciTech Connect

    Sen, Ugur; Sen, Saduman

    2003-06-15

    In this study, the fracture toughness of boride layers of two borided cold work tool steels have been investigated. Boriding was carried out in a salt bath consisting of borax, boric acid, ferro-silicon and aluminum. Boriding was performed at 850 and 950 deg. C for 2 to 7 h. The presence of boride phases were determined by X-ray diffraction (XRD) analysis. Hardness and fracture toughness of borides were measured via Vickers indenter. Increasing of boriding time and temperature leads to reduction of fracture toughness of borides. Metallographic examination showed that boride layer formed on cold work tool steels was compact and smooth.

  3. Oriented microtexturing on the surface of high-speed steel cutting tool

    NASA Astrophysics Data System (ADS)

    Filippov, A. V.; Tarasov, S. Yu.; Podgornyh, O. A.; Shamarin, N. N.; Filippova, E. O.

    2016-11-01

    Microtexturing the metal cutting tool surfaces is a novel technique intended for enhancing the workability of these tools. The microtexturing is used in machining the titanium alloys for air-space applications for reducing the adhesion wear of metal cutting blades. This paper is focused on forming the microtextured dotted, banded and overlapped areas on the surfaces of high-speed steel samples. The treated areas have been examined using laser scanning microscopy for the microtexture pattern and roughness. It has been shown that the microtextured surfaces obtained on the high-speed steel samples were free of cracks. Surface pattern and roughness of all three microtextured areas have been examined and analyzed.

  4. High Speed Turning of H-13 Tool Steel Using Ceramics and PCBN

    NASA Astrophysics Data System (ADS)

    Umer, Usama

    2012-09-01

    H-13 is the toughest tool steel used in machined die casting and forging dies. Due to its extreme hardness and poor thermal conductivity high speed cutting results in high temperature and stresses. This gives rise to surface damage of the workpiece and accelerated tool wear. This study evaluates the performance of different tools including ceramics and PCBN using practical finite element simulations and high speed orthogonal cutting tests. The machinability of H-13 was evaluated by tool wear, surface roughness, and cutting force measurements. From the 2D finite element model for orthogonal cutting, stresses and temperature distributions were predicted and compared for the different tool materials.

  5. Effect of treatment by a pulsed magnetic field on the hardness and fracture strength of a hypereutectoid tool steel

    NASA Astrophysics Data System (ADS)

    Vorob'ev, R. A.; Dubinskii, V. N.

    2014-08-01

    Using samples of quenched U10A tool steel (AISI/SAE W1-1.0C steel), the possibility of selecting a regime of the magnetic pulsed treatment that provides a simultaneous increase of the Vickers hardness and fracture resistance (the load that induces a crack nucleation from the indent) that would insure an increase in the steel ductility and resistance of tools produced from it has been demonstrated.

  6. Microstructure and Properties of Selective Laser Melted High Hardness Tool Steel

    NASA Astrophysics Data System (ADS)

    Feuerhahn, F.; Schulz, A.; Seefeld, T.; Vollertsen, F.

    A secondary hardening tool steel material X110CrMoVAl 8-2 was successfully processed by selective laser melting (SLM), producing defect free samples of high density. The microstructure appeared irregular after SLM, which was attributed to locally different temper states in consequence of the SLM process pattern. By a subsequent heat treatment, a homogeneous microstructure with ultrafine carbide precipitations and a very high resulting hardness of 765 HV were achieved. The hardness came very close to that of the same material processed by spray forming and forging, whilst the SLM microstructure was significantly finer. Therefore this tool steel material was considered as highly promising for SLM manufacturing of tools, e.g. for micro tooling applications.

  7. Machine Tool Layout: Outlining a Basic Shape on Flat Steel. Fordson Bilingual Demonstration Project.

    ERIC Educational Resources Information Center

    Ochsner, Alan

    This vocational instructional module on outlining a basic shape on flat steel is one of eight such modules designed to assist recently arrived Arab students, limited in English proficiency (LEP), in critical instructional areas in a comprehensive high school. Goal stated for this module is for the student enrolled in a machine tool course to…

  8. Development of Cutting Tool Through Superplastic Boronizing of Duplex Stainless Steel

    NASA Astrophysics Data System (ADS)

    Jauhari, Iswadi; Harun, Sunita; Jamlus, Siti Aida; Sabri, Mohd Faizul Mohd

    2017-01-01

    In this study, a cutting tool is developed from duplex stainless steel (DSS) using the superplastic boronizing technique. The feasibility of the development process is studied, and the cutting performances of the cutting tool are evaluated and compared with commercially available carbide and high-speed steel (HSS) tools. The superplastically boronized (SPB) cutting tool yielded a dense boronized layer of 50.5 µm with a surface hardness of 3956 HV. A coefficient of friction value of 0.62 is obtained, which is lower than 1.02 and 0.8 of the carbide and HSS tools. When tested on an aluminum 6061 surface under dry condition, the SPB cutting tool is also able to produce turning finishing below 0.4 µm, beyond the travel distance of 3000 m, which is comparable to the carbide tool, but produces much better results than HSS tool. Through superplastic boronizing of DSS, it is possible to produce a high-quality metal-based cutting tool that is comparable to the conventional carbide tool.

  9. Development of Cutting Tool Through Superplastic Boronizing of Duplex Stainless Steel

    NASA Astrophysics Data System (ADS)

    Jauhari, Iswadi; Harun, Sunita; Jamlus, Siti Aida; Sabri, Mohd Faizul Mohd

    2017-03-01

    In this study, a cutting tool is developed from duplex stainless steel (DSS) using the superplastic boronizing technique. The feasibility of the development process is studied, and the cutting performances of the cutting tool are evaluated and compared with commercially available carbide and high-speed steel (HSS) tools. The superplastically boronized (SPB) cutting tool yielded a dense boronized layer of 50.5 µm with a surface hardness of 3956 HV. A coefficient of friction value of 0.62 is obtained, which is lower than 1.02 and 0.8 of the carbide and HSS tools. When tested on an aluminum 6061 surface under dry condition, the SPB cutting tool is also able to produce turning finishing below 0.4 µm, beyond the travel distance of 3000 m, which is comparable to the carbide tool, but produces much better results than HSS tool. Through superplastic boronizing of DSS, it is possible to produce a high-quality metal-based cutting tool that is comparable to the conventional carbide tool.

  10. Locating liquid and gas interfaces behind a steel hull: a neutron backscatter tool in action.

    PubMed

    Hogenbirk, A; Hartog, F A

    2005-01-01

    Monte Carlo simulations were performed to prove that a neutron backscatter tool can detect liquid (hydrocarbon or water) and gas levels behind steel casings, even when used under water. Consequently such a tool can be applied to the detection of fluid levels in wrecked vessels, which is important for environmentally safe retrieval of oil in these vessels. These simulations enable the efficient optimisation of the experimental conditions, without having to resort to expensive mock-ups.

  11. Irradiation-induced embrittlement of a 2.25Cr1Mo steel

    NASA Astrophysics Data System (ADS)

    Song, S.-H.; Faulkner, R. G.; Flewitt, P. E. J.; Smith, R. F.; Marmy, P.; Victoria, M.

    2000-07-01

    Irradiation-induced embrittlement of a 2.25Cr1Mo is investigated by means of small punch testing and scanning electron microscopy (SEM). The ductile-brittle transition temperature (DBTT) determined by the small punch test is much lower than that determined by the standard Charpy test. There are some irradiation-induced embrittlement effects after the steel is irradiated at about 270°C for 46 days with a neutron dose rate of 1.05×10 -8 dpa s -1 and at about 400°C for 86 days with a neutron dose rate of 1.75×10 -8 dpa s -1. In addition, there is some temper embrittlement after the steel is aged at about 400°C for 86 days.

  12. Built-up edge effect on tool wear when turning steels at low cutting speed

    NASA Astrophysics Data System (ADS)

    Cassier, Zulay; Prato, Yidney; Muñoz-Escalona, Patricia

    2004-10-01

    In any machining process, it is very important to control the cutting variables used during the process because these will affect, for example, tool life and workpiece surface roughness. Since the built-up edge (BUE) increases the wear of the tool and affects the surface roughness of the workpiece, the study of this phenomenon is very important in predicting and minimizing the wear of a cutting tool. This research studies the influence of the BUE formation for coated carbide tools when turning medium- and high-strength steels. Different mathematical expressions were obtained to quantify this effect. Mathematical expressions for uncoated carbide tools were not possible to obtain, due to the fact that for these tools an increase in the wear and their premature fracture was observed.

  13. Effects of machining parameters on tool life and its optimization in turning mild steel with brazed carbide cutting tool

    NASA Astrophysics Data System (ADS)

    Dasgupta, S.; Mukherjee, S.

    2016-09-01

    One of the most significant factors in metal cutting is tool life. In this research work, the effects of machining parameters on tool under wet machining environment were studied. Tool life characteristics of brazed carbide cutting tool machined against mild steel and optimization of machining parameters based on Taguchi design of experiments were examined. The experiments were conducted using three factors, spindle speed, feed rate and depth of cut each having three levels. Nine experiments were performed on a high speed semi-automatic precision central lathe. ANOVA was used to determine the level of importance of the machining parameters on tool life. The optimum machining parameter combination was obtained by the analysis of S/N ratio. A mathematical model based on multiple regression analysis was developed to predict the tool life. Taguchi's orthogonal array analysis revealed the optimal combination of parameters at lower levels of spindle speed, feed rate and depth of cut which are 550 rpm, 0.2 mm/rev and 0.5mm respectively. The Main Effects plot reiterated the same. The variation of tool life with different process parameters has been plotted. Feed rate has the most significant effect on tool life followed by spindle speed and depth of cut.

  14. Influence of Cooling Rate on Phase Formationin Spray-Formed H13 Tool Steel

    SciTech Connect

    K. M. Mchugh; Y. Lin; Y. Zhou; E. J. Lavernia

    2006-04-01

    Spray forming is an effective way to process many tool steels into near-net-shape molds, dies and related tooling. The general approach involves depositing atomized droplets onto a refractory pattern in order to image the pattern’s features. The pattern is removed and the die is fitted into a standard holding fixture. This approach results in significant cost and lead-time savings compared to conventional machining, Spray-formed dies perform well in many industrial forming operations, oftentimes exhibiting extended die life over conventional dies. Care must be exercised when spray forming tool steel dies to minimize porosity and control the nature and distribution of phases and residual stresses. Selection of post-deposition heat treatment is important to tailor the die’s properties (hardness, strength, impact energy, etc.) for a particular application. This paper examines how the cooling rate and other processing parameters during spray processing and heat treatment of H13 tool steel influence phase formation. Results of case studies on spray-formed die performance in forging, extrusion and die casting, conducted by industry during production runs, will be described.

  15. Internal grinding of high-speed steels: Shorter processing times with boron nitride grinding tools

    NASA Astrophysics Data System (ADS)

    Borse, D.

    Boron nitride grinding tools can be used to advantage for the grinding of high speed steel (HSS) with a high vanadium content. the abrasives available to date are of limited value because the HSS materials contain very hard carbides, grinding of which, and of vanadium carbide in particular, results in very rapid wear in silicon carbide or corundum grinding wheels. The hardness of these steels is usually 62 RC to 70 RC. Boron nitride grinding tools are advantageous for internal grinding of workpieces made of high speed steel for example, sockets, milling tool bores, cutting wheels and crushing rollers. To date, boron nitride grinding wheels or pencil grinders were bonded with synthetic resin. Consequently internal grinding is usually carried out as wet grinding. In the meantime grinding tools bonded with electrodeposited metal bonds (GSS) were developed and proved to be successful for internal grinding. The abrasive grains which are arranged in a single layer protrude freely from the electrobond. During grinding very little heat is generated, so that dry grinding is possible.

  16. Optimization of Processing Parameters in ECM of Die Tool Steel Using Nanofluid by Multiobjective Genetic Algorithm.

    PubMed

    Sathiyamoorthy, V; Sekar, T; Elango, N

    2015-01-01

    Formation of spikes prevents achievement of the better material removal rate (MRR) and surface finish while using plain NaNO3 aqueous electrolyte in electrochemical machining (ECM) of die tool steel. Hence this research work attempts to minimize the formation of spikes in the selected workpiece of high carbon high chromium die tool steel using copper nanoparticles suspended in NaNO3 aqueous electrolyte, that is, nanofluid. The selected influencing parameters are applied voltage and electrolyte discharge rate with three levels and tool feed rate with four levels. Thirty-six experiments were designed using Design Expert 7.0 software and optimization was done using multiobjective genetic algorithm (MOGA). This tool identified the best possible combination for achieving the better MRR and surface roughness. The results reveal that voltage of 18 V, tool feed rate of 0.54 mm/min, and nanofluid discharge rate of 12 lit/min would be the optimum values in ECM of HCHCr die tool steel. For checking the optimality obtained from the MOGA in MATLAB software, the maximum MRR of 375.78277 mm(3)/min and respective surface roughness Ra of 2.339779 μm were predicted at applied voltage of 17.688986 V, tool feed rate of 0.5399705 mm/min, and nanofluid discharge rate of 11.998816 lit/min. Confirmatory tests showed that the actual performance at the optimum conditions was 361.214 mm(3)/min and 2.41 μm; the deviation from the predicted performance is less than 4% which proves the composite desirability of the developed models.

  17. Optimization of Processing Parameters in ECM of Die Tool Steel Using Nanofluid by Multiobjective Genetic Algorithm

    PubMed Central

    Sathiyamoorthy, V.; Sekar, T.; Elango, N.

    2015-01-01

    Formation of spikes prevents achievement of the better material removal rate (MRR) and surface finish while using plain NaNO3 aqueous electrolyte in electrochemical machining (ECM) of die tool steel. Hence this research work attempts to minimize the formation of spikes in the selected workpiece of high carbon high chromium die tool steel using copper nanoparticles suspended in NaNO3 aqueous electrolyte, that is, nanofluid. The selected influencing parameters are applied voltage and electrolyte discharge rate with three levels and tool feed rate with four levels. Thirty-six experiments were designed using Design Expert 7.0 software and optimization was done using multiobjective genetic algorithm (MOGA). This tool identified the best possible combination for achieving the better MRR and surface roughness. The results reveal that voltage of 18 V, tool feed rate of 0.54 mm/min, and nanofluid discharge rate of 12 lit/min would be the optimum values in ECM of HCHCr die tool steel. For checking the optimality obtained from the MOGA in MATLAB software, the maximum MRR of 375.78277 mm3/min and respective surface roughness Ra of 2.339779 μm were predicted at applied voltage of 17.688986 V, tool feed rate of 0.5399705 mm/min, and nanofluid discharge rate of 11.998816 lit/min. Confirmatory tests showed that the actual performance at the optimum conditions was 361.214 mm3/min and 2.41 μm; the deviation from the predicted performance is less than 4% which proves the composite desirability of the developed models. PMID:26167538

  18. Impact of tool wear on joint strength in friction stir spot welding of DP 980 steel

    SciTech Connect

    Miles, Michael; Ridges, Chris; Hovanski, Yuri; Peterson, Jeremy; Santella, M. L.; Steel, Russel

    2011-09-14

    Friction stir spot welding has been shown to be a viable method of joining ultra high strength steel (UHSS), both in terms of joint strength and process cycle time. However, the cost of tooling must be reasonable in order for this method to be adopted as an industrial process. Recently a new tool alloy has been developed, using a blend of PCBN and tungsten rhenium (W-Re) in order to improve the toughness of the tool. Wear testing results are presented for two of these alloys: one with a composition of 60% PCBN and 40% W-Re, and one with 70% PCBN and 30% W-Re. The sheet material used for all wear testing was 1.4 mm DP 980. Lap shear testing was used to show the relationship between tool wear and joint strength. The Q70 tool provided the best combination of wear resistance and joint strength.

  19. Effect of Continuous and Isothermal Hardening on the Wear Resistance of Tools Produced from High-Speed Steels

    NASA Astrophysics Data System (ADS)

    Murav'ev, V. I.; Chernobai, S. P.

    2003-05-01

    The effect of isothermal hardening on the red-hardness (heat resistance) of steel R18 is studied. A complex dependence of the red hardness on the temperature of isothermal hardening and the hold time is shown. Tools from steel R18 are shown to have maximum heat resistance and wear resistance after bainitic hardening in the "pre-transformation" range.

  20. Development and selection of heat-resistant tool steels for water-cooled dies

    NASA Astrophysics Data System (ADS)

    Kremney, L. S.; Zabezhinskii, A. Ya.

    1980-02-01

    Alloying and heat treatment of tool steels for water-cooled dies to improve the service life in high-speed automatic presses must ensure: 1) The lowest but still sufficient level of hardening during precipitation hardening; 2) the smallest amount of carbide not dissolved during quenching; 3) prevention of the decomposition of martensite in grain boundaries during tempering; 4) a structure of lath martensite.

  1. Surface Preparation of Powder Metallurgical Tool Steels by Means of Wire Electrical Discharge Machining

    NASA Astrophysics Data System (ADS)

    Hatami, Sepehr; Shahabi-Navid, Mehrdad; Nyborg, Lars

    2012-09-01

    The surface of two types of powder metallurgical (PM) tool steels ( i.e., with and without nitrogen) was prepared using wire electrical discharge machining (WEDM). From each grade of tool steel, seven surfaces corresponding to one to seven passes of WEDM were prepared. The WEDM process was carried out using a brass wire as electrode and deionized water as dielectric. After each WEDM pass the surface of the tool steels was thoroughly examined. Surface residual stresses were measured by the X-ray diffraction (XRD) technique. The measured stresses were found to be of tensile nature. The surface roughness of the WEDM specimens was measured using interference microscopy. The surface roughness as well as the residual stress measurements indicated an insignificant improvement of these parameters after four passes of WEDM. In addition, the formed recast layer was characterized by means of scanning electron microscopy (SEM), XRD, and X-ray photoelectron spectroscopy (XPS). The characterization investigation clearly shows diffusion of copper and zinc from the wire electrode into the work material, even after the final WEDM step. Finally, the importance of eliminating excessive WEDM steps is thoroughly discussed.

  2. Microstructural evolution of a heat-treated H23 tool steel

    NASA Astrophysics Data System (ADS)

    Nurbanasari, Meilinda; Tsakiropoulos, Panos; Palmiere, Eric J.

    2015-03-01

    The microstructure and the stability of carbides after heat treatments in an H23 tool steel were investigated. The heat treatments consisted of austenization at two different austenizing temperatures (1100°C and 1250°C), followed by water quenching and double-aging at 650°C, 750°C, and 800°C with air cooling between the first and second aging treatments. Martensite did not form in the as-quenched microstructures, which consisted of a ferrite matrix, M6C, M7C3, and MC carbides. The double-aged microstructures consisted of a ferrite matrix and MC, M6C, M7C3, and M23C6 carbides. Secondary hardening as a consequence of secondary precipitation of fine M2C carbides did not occur. There was disagreement between the experimental microstructure and the results of thermodynamic calculations. The highest double-aged hardness of the H23 tool steel was 448 HV after austenization at 1250°C and double-aging at 650°C, which suggested that this tool steel should be used at temperatures below 650°C.

  3. Effect of Initial Hardness on Interfacial Features in Underwater Explosive Welding of Tool Steel SKS3

    NASA Astrophysics Data System (ADS)

    Sun, Wei; Li, Xiaojie; Yan, Honghao; Hokamoto, Kazuyuki

    2013-11-01

    This paper aims at investigating effects of initial hardness on interfacial features for identical compositional materials under identical welding conditions. Two underwater explosive welding experiments on tool steel SKS3 with copper foil were carried out: one as-received and the other heat-treated. The welding process was simulated using the commercially available software package LS-DYNA. Numerical simulation gave deformation of the flyer/base plate and pressure distribution during the welding process. Microstructure and hardness at interface of the welded metals were evaluated. The results indicate that decreasing impact energy is accompanied by a shift from wavy to linear interface. Moreover, a comparison of the two experiments allows the conclusion that high initial hardness results in a decrease of wavelength and amplitude under identical welding conditions. Hardness profiles of as-received tool steel-copper welding reveal the hardening effect of impact in the vicinity of the interface. However, of interest is that a decrease in hardness was seen in the case of heat-treated martensitic tool steel with copper, fundamentally differing from previous explosive welding research; phase transition is proposed to discuss the relation between the effects of impact and heat, and those of work hardening and softening.

  4. Influence of intermetallic coatings of system Ti-Al on durability of slotting tool from high speed steel

    NASA Astrophysics Data System (ADS)

    Vardanyan, E. L.; Budilov, V. V.; Ramazanov, K. N.; Khusnimardanov, R. N.; Nagimov, R. Sh

    2017-05-01

    The operation conditions and mechanism of wear of slotting tools from high-speed steel was researched. The analysis of methods increasing durability was carried out. The effect of intermetallic coatings deposited from vacuum-arc discharge plasma on the physical-mechanical high-speed steel EP657MP was discovered. The pilot batch of the slotting tool and production tests were carried out.

  5. Microstructural study and densification analysis of hot work tool steel matrix composites reinforced with TiB{sub 2} particles

    SciTech Connect

    Fedrizzi, A.; Pellizzari, M.; Zadra, M.; Marin, E.

    2013-12-15

    Hot work tool steels are characterized by good toughness and high hot hardness but are less wear resistant than other tooling materials, such as high speed steel. Metal matrix composites show improved tribological behavior, but not much work has been done in the field of hot work tool steels. In this paper TiB{sub 2}-reinforced hot work tool steel matrix composites were produced by spark plasma sintering (SPS). Mechanical alloying (MA) was proposed as a suited process to improve the composite microstructure. Density measurements and microstructure confirmed that MA promotes sintering and produces a fine and homogeneous dispersion of reinforcing particles. X-ray diffraction patterns of the sintered composites highlighted the formation of equilibrium Fe{sub 2}B and TiC, as predicted by thermodynamic calculations using Thermo-Calc® software. Scanning electron microscopy as well as scanning Kelvin probe force microscopy highlighted the reaction of the steel matrix with TiB{sub 2} particles, showing the formation of a reaction layer at the TiB{sub 2}-steel interface. Phase investigations pointed out that TiB{sub 2} is not chemically stable in steel matrix because of the presence of carbon even during short time SPS. - Highlights: • TiB{sub 2} reinforced steel matrix composites were produced by spark plasma sintering. • TiB{sub 2} was successfully dispersed in the steel matrix by mechanical alloying. • Steel and TiB{sub 2} react during sintering forming equilibrium Fe{sub 2}B and TiC. • The new phases were investigated by means of AFM, Volta potential and XRD analyses.

  6. Wear testing of friction stir spot welding tools for joining of DP 980 Steel

    SciTech Connect

    Ridges, Chris; Miles, Michael; Hovanski, Yuri; Peterson, Jeremy; Steel, Russell

    2011-06-06

    Friction stir spot welding has been shown to be a viable method of joining ultra high strength steel (UHSS), both in terms of joint strength and process cycle time. However, the cost of tooling must be reasonable in order for this method to be adopted as an industrial process. Several tooling materials have been evaluated in prior studies, including silicon nitride and polycrystalline cubic boron nitride (PCBN). Recently a new tool alloy has been developed, where a blend of PCBN and tungsten rhenium (W-Re) was used in order to improve the toughness of the tool. Wear testing results are presented for two of these alloys: one with a composition of 60% PCBN and 40% W-Re (designated as Q60), and one with 70% PCBN and 30% W-Re (designated at Q70). The sheet material used for all wear testing was DP 980. Tool profiles were measured periodically during the testing process in order to show the progression of wear as a function of the number of spots produced. Lap shear testing was done each time a tool profile was taken in order to show the relationship between tool wear and joint strength. For the welding parameters chosen for this study the Q70 tool provided the best combination of wear resistance and joint strength.

  7. The effect of boriding on wear resistance of cold work tool steel

    NASA Astrophysics Data System (ADS)

    Anzawa, Y.; Koyama, S.; Shohji, I.

    2017-05-01

    Recently, boriding has attracted extensive attention as surface stiffening processing of plain steel. In this research, the influence of processing time on the formation layer of cold work tool steel (KD11MAX) by Al added fused salt bath was examined. In addition, in order to improve the abrasion resistance of KD11MAX, the effect of the treatment of boronization on the formation layer has been investigated. Boriding were performed in molten borax which contained about 10 mass% Al at processing time of 1.8 ~ 7.2 ks (processing temperature of 1303 K). As a result of the examination, the hardness of the boriding layer becomes about 1900 HV when the processing time of 3.6 ks. Also the abrasion resistance has improved remarkably. Furthermore, it was revealed that the formation layer was boronized iron from the Vickers hardness and analysis of the X-ray diffraction measurement.

  8. Thixoforming of Steel: New Tools Conception to Analyse Thermal Exchanges and Strain Rate Effects

    SciTech Connect

    Cezard, P.; Bigot, R.; Becker, E.; Mathieu, S.; Pierret, J. C.; Rassili, A.

    2007-04-07

    Through different papers, authors shown that the influence of thermal exchanges was a first order parameter on the semi-solid steel behaviour, and certainly for every semi-solid metallic materials. These thermal exchanges hide other parameters effect like, for example, the strain rate influence. This paper tries to determine the influence of these two parameters by using a new extrusion device on a hydraulic press. This new tools conception annihilated the influence of the decrease of the punch speed before stopping and permitted to have a constant speed during the experiment. This work also deals with the homogeneous flow during thixoforming of steel and shows the importance to couple initial temperature of the slug with punch speed. This paper presents different conditions which permitted to have a homogeneous flow by keeping a low load.

  9. Experimental investigation on geometrical aspects of micro-plasma deposited tool steel for repair applications

    NASA Astrophysics Data System (ADS)

    Jhavar, S.; Paul, C. P.; Jain, N. K.

    2014-08-01

    Recent advancement in direct material deposition processes found wide applications in rapid prototyping, manufacturing and tooling industry. Micro-plasma deposition is one of the recent developments in this domain. This paper reports the deployment of newly integrated micro-plasma deposition system for the deposition of AISI P-20 tool steel on the AISI P20 tool steel substrate. A number of test tracks for single track deposition were deposited at the various combination of processing parameters. The sets of parameters yielding good deposits were selected to deposit overlap tracks. The geometry of single and overlapped tracks was evaluated to understand the parametric dependence. The study indicates that the aspect ratio of track geometry (ratio of width to height of track) is dependent on the processing parameters and the discharge current is identified as the most dominating parameters (contribution = 44%), followed by scan speed (contribution = 26.68%) and wire feed rate (contribution = 26.98%) with almost same effect. The microscopic study of the deposits indicates that the material deposited at the optimum processing parameters is free from surface and bulk defects. The estimated material properties are found to be at par with conventional processed material. This feasibility study proved that the micro-plasma deposition can be used for the generation of surfaces and multi-featured material deposition. It paved a way for the application of the process in die/mold repairs.

  10. Improvement of Laser Deposited High Alloyed Powder Metallurgical Tool Steel by a Post-tempering Treatment

    NASA Astrophysics Data System (ADS)

    Leunda, J.; Navas, V. García; Soriano, C.; Sanz, C.

    Laser cladding process of a high alloyed powder metallurgical tool steel was studied for die repairing purposes. The low hardness obtained after the deposition process was improved by later tempering cycles, achieving crack free coatings with hardness well above 700 HV. The effect of different post tempering cycles was investigated in order to determine the optimal temperature range. The microstructure of the samples was studied using optical and scanning electron microscope and the volumetric ratio of retained austenite was determined by X-ray diffraction. The tempering effect was mainly evaluated through cross-section microhardness profiles.

  11. Effect of TiC addition on surface oxidation behavior of SKD11 tool steel composites

    NASA Astrophysics Data System (ADS)

    Cho, Seungchan; Jo, Ilguk; Kim, Heebong; Kwon, Hyuk-Tae; Lee, Sang-Kwan; Lee, Sang-Bok

    2017-09-01

    Titanium carbide (TiC) reinforced tool steel matrix composites were successfully fabricated by a liquid pressing infiltration process and research was subsequently conducted to investigate the composites' oxidation resistance. The mass gain of the tested TiC-SKD11 composite held at 700 °C for 50 h in an air environment decreased by about 60%, versus that of the SKD11, which indicates improved oxidation resistance. Improved oxidation resistance of the TiC-SKD11 composite originates from uniformly reinforced TiC, with a phase transition to thermodynamically stable, volume-expanded TiO2.

  12. Development of a robust modeling tool for radiation-induced segregation in austenitic stainless steels

    SciTech Connect

    Yang, Ying; Field, Kevin G; Allen, Todd R.; Busby, Jeremy T

    2015-09-01

    Irradiation-assisted stress corrosion cracking (IASCC) of austenitic stainless steels in Light Water Reactor (LWR) components has been linked to changes in grain boundary composition due to irradiation induced segregation (RIS). This work developed a robust RIS modeling tool to account for thermodynamics and kinetics of the atom and defect transportation under combined thermal and radiation conditions. The diffusion flux equations were based on the Perks model formulated through the linear theory of the thermodynamics of irreversible processes. Both cross and non-cross phenomenological diffusion coefficients in the flux equations were considered and correlated to tracer diffusion coefficients through Manning’s relation. The preferential atomvacancy coupling was described by the mobility model, whereas the preferential atom-interstitial coupling was described by the interstitial binding model. The composition dependence of the thermodynamic factor was modeled using the CALPHAD approach. Detailed analysis on the diffusion fluxes near and at grain boundaries of irradiated austenitic stainless steels suggested the dominant diffusion mechanism for chromium and iron is via vacancy, while that for nickel can swing from the vacancy to the interstitial dominant mechanism. The diffusion flux in the vicinity of a grain boundary was found to be greatly influenced by the composition gradient formed from the transient state, leading to the oscillatory behavior of alloy compositions in this region. This work confirms that both vacancy and interstitial diffusion, and segregation itself, have important roles in determining the microchemistry of Fe, Cr, and Ni at irradiated grain boundaries in austenitic stainless steels.

  13. Dimensional and material characteristics of direct deposited tool steel by CO II laser

    NASA Astrophysics Data System (ADS)

    Choi, J.

    2006-01-01

    Laser aided direct metalimaterial deposition (DMD) process builds metallic parts layer-by-layer directly from the CAD representation. In general, the process uses powdered metaUmaterials fed into a melt pool, creating fully dense parts. Success of this technology in the die and tool industry depends on the parts quality to be achieved. To obtain designed geometric dimensions and material properties, delicate control of the parameters such as laser power, spot diameter, traverse speed and powder mass flow rate is critical. In this paper, the dimensional and material characteristics of directed deposited H13 tool steel by CO II laser are investigated for the DMD process with a feedback height control system. The relationships between DMD process variables and the product characteristics are analyzed using statistical techniques. The performance of the DMD process is examined with the material characteristics of hardness, porosity, microstructure, and composition.

  14. Surface modification of AISI H13 tool steel by laser cladding with NiTi powder

    NASA Astrophysics Data System (ADS)

    Norhafzan, B.; Aqida, S. N.; Chikarakara, E.; Brabazon, D.

    2016-04-01

    This paper presents laser cladding of NiTi powder on AISI H13 tool steel surface for surface properties enhancement. The cladding process was conducted using Rofin DC-015 diffusion-cooled CO2 laser system with wavelength of 10.6 µm. NiTi powder was pre-placed on H13 tool steel surface. The laser beam was focused with a spot size of 90 µm on the sample surface. Laser parameters were set to 1515 and 1138 W peak power, 18 and 24 % duty cycle and 2300-3500 Hz laser pulse repetition frequency. Hardness properties of the modified layer were characterized by Wilson Hardness tester. Metallographic study and chemical composition were conducted using field emission scanning electron microscope and energy-dispersive X-ray spectrometer (EDXS) analysis. Results showed that hardness of NiTi clad layer increased three times that of the substrate material. The EDXS analysis detected NiTi phase presence in the modified layer up to 9.8 wt%. The metallographic study shows high metallurgical bonding between substrate and modified layer. These findings are significant to both increased hardness and erosion resistance of high-wear-resistant components and elongating their lifetime.

  15. Crystalline gamma-Al2O3 physical vapour deposition-coating for steel thixoforging tools.

    PubMed

    Bobzin, K; Hirt, G; Bagcivan, N; Khizhnyakova, L; Ewering, M

    2011-10-01

    The process of thixoforming, which has been part of many researches during the last decades, combines the advantages of forging and casting for the shaping of metallic components. But due to the high temperatures of semi-solid steel alloys high demands on the tools are requested. To resists the thermal and mechanical loads (wear, friction, thermal and thermomechanical fatigue) protecting thin films are necessary. In this regard crystalline gamma-Al2O3 deposited via Physical Vapour Deposition (PVD) is a promising candidate: It exhibits high thermal stability, high oxidation resistance and high hot hardness. In the present work the application of a (Ti, Al)N/gamma-Al2O3 coating deposited by means of Magnetron Sputter Ion Plating in an industrial coating unit is presented. The coating was analysed by means of Rockwell test, nanoindentation, and Scanning Electron Microscopy (SEM). The coated tool was tested in thixoforging experiments with steel grade X210CrW12 (AlSI D6). The surface of the coated dies was examined with Scanning Electron Microscope (SEM) after 22, 42, 90 and 170 forging cycles.

  16. Mechanical characteristics of a tool steel layer deposited by using direct energy deposition

    NASA Astrophysics Data System (ADS)

    Baek, Gyeong Yun; Shin, Gwang Yong; Lee, Eun Mi; Shim, Do Sik; Lee, Ki Yong; Yoon, Hi-Seak; Kim, Myoung Ho

    2017-07-01

    This study focuses on the mechanical characteristics of layered tool steel deposited using direct energy deposition (DED) technology. In the DED technique, a laser beam bonds injected metal powder and a thin layer of substrate via melting. In this study, AISI D2 substrate was hardfaced with AISI H13 and M2 metal powders for mechanical testing. The mechanical and metallurgical characteristics of each specimen were investigated via microstructure observation and hardness, wear, and impact tests. The obtained characteristics were compared with those of heat-treated tool steel. The microstructures of the H13- and M2-deposited specimens show fine cellular-dendrite solidification structures due to melting and subsequent rapid cooling. Moreover, the cellular grains of the deposited M2 layer were smaller than those of the H13 structure. The hardness and wear resistance were most improved in the M2-deposited specimen, yet the H13-deposited specimen had higher fracture toughness than the M2-deposited specimen and heat-treated D2.

  17. Two dimensional finite element thermal model of laser surface glazing for H13 tool steel

    NASA Astrophysics Data System (ADS)

    Kabir, I. R.; Yin, D.; Naher, S.

    2016-10-01

    A two dimensional (2D) transient thermal model with line-heat-source was developed by Finite Element Method (FEM) for laser surface glazing of H13 tool steel using commercial software-ANSYS 15. The geometry of the model was taken as a transverse circular cross-section of cylindrical specimen. Two different power levels (300W, 200W) were used with 0.2mm width of laser beam and 0.15ms exposure time. Temperature distribution, heating and cooling rates, and the dimensions of modified surface were analysed. The maximum temperatures achieved were 2532K (2259°C) and 1592K (1319°C) for laser power 300W and 200W respectively. The maximum cooling rates were 4.2×107 K/s for 300W and 2×107 K/s for 200W. Depths of modified zone increased with increasing laser power. From this analysis, it can be predicted that for 0.2mm beam width and 0.15ms time exposer melting temperature of H13 tool steel is achieved within 200-300W power range of laser beam in laser surface glazing.

  18. Wear of Cutting Tool with Excel Geometry in Turning Process of Hardened Steel

    NASA Astrophysics Data System (ADS)

    Samardžiová, Michaela

    2016-09-01

    This paper deals with hard turning using a cutting tool with Xcel geometry. This is one of the new geometries, and there is not any information about Xcel wear in comparison to the conventional geometry. It is already known from cutting tools producers that using the Xcel geometry leads to higher quality of machined surface, perticularly surface roughness. It is possible to achieve more than 4 times lower Ra and Rz values after turning than after using conventional geometry with radius. The workpiece material was 100Cr6 hardened steel with hardness of 60 ± 1 HRC. The machine used for the experiment was a lathe with counter spindle DMG CTX alpha 500, which is located in the Centre of Excellence of 5-axis Machining at the Faculty of Materials Science and Technology in Trnava. The cutting tools made by CBN were obtained from Sandvik COROMANT Company. The aim of this paper is to investigate the cutting tool wear in hard turning process by the Xcel cutting tool geometry.

  19. Tribology and Tool Wear of Hot Dip Galvanized Zinc Magnesium Alloys on Cold Rolled Steel Sheets

    NASA Astrophysics Data System (ADS)

    Raab, A. E.; Berger, E.; Freudenthaler, J.; Leomann, F.; Walch, C.

    2011-05-01

    Recently zinc based coatings on cold rolled steel with improved functionality in terms of forming and/or corrosion behaviour have been intensively investigated in the steel industry1,2,3. One of the most promising products are zinc magnesium alloys produced in hot dip galvanizing process. These coatings were already introduced in construction industry a few years ago1. With some modifications the improved properties of the coating are also interesting for automotive industry. In the present work the tribological potential of hot dip galvanized zinc magnesium coatings (HDG/ZM) produced at an industrial line under regular production, was studied in terms of sliding properties, adhesive and abrasive tool wear. First a short introduction into surface morphology of HDG/ZM will be given. For the tribological characterization of the material, which is the main topic of the contribution, different tests were performed on hot dip galvanised zinc magnesium material and results were compared with classic hot dip galvanized zinc coating (HDG/Z). The investigations are mainly based on the strip draw test which allows the determination of the friction coefficient directly by using a constant contact pressure. Deep drawing property was tested by forming model cups. The abrasive tool wear was tested using a standard test for material used in automotive industry. The adhesive tool wear was investigated by characterizing the coating material transferred to the tool in the strip draw test. All performed tests show an improved drawability of HDG/ZM compared to classical HDG/Z reference material. However the most promising difference between HDG/ZM and HDG/Z is that galling was found to be less for HDG/ZM than for HDG/Z. Therefore HDG/ZM is an interesting system not only with respect to corrosion protection but also in terms of tribology and provides clear advantages in formability.

  20. Tribology and Tool Wear of Hot Dip Galvanized Zinc Magnesium Alloys on Cold Rolled Steel Sheets

    SciTech Connect

    Raab, A. E.; Berger, E.; Freudenthaler, J.; Leomann, F.; Walch, C.

    2011-05-04

    Recently zinc based coatings on cold rolled steel with improved functionality in terms of forming and/or corrosion behaviour have been intensively investigated in the steel industry. One of the most promising products are zinc magnesium alloys produced in hot dip galvanizing process. These coatings were already introduced in construction industry a few years ago. With some modifications the improved properties of the coating are also interesting for automotive industry. In the present work the tribological potential of hot dip galvanized zinc magnesium coatings (HDG/ZM) produced at an industrial line under regular production, was studied in terms of sliding properties, adhesive and abrasive tool wear.First a short introduction into surface morphology of HDG/ZM will be given. For the tribological characterization of the material, which is the main topic of the contribution, different tests were performed on hot dip galvanised zinc magnesium material and results were compared with classic hot dip galvanized zinc coating (HDG/Z). The investigations are mainly based on the strip draw test which allows the determination of the friction coefficient directly by using a constant contact pressure. Deep drawing property was tested by forming model cups. The abrasive tool wear was tested using a standard test for material used in automotive industry. The adhesive tool wear was investigated by characterizing the coating material transferred to the tool in the strip draw test.All performed tests show an improved drawability of HDG/ZM compared to classical HDG/Z reference material. However the most promising difference between HDG/ZM and HDG/Z is that galling was found to be less for HDG/ZM than for HDG/Z. Therefore HDG/ZM is an interesting system not only with respect to corrosion protection but also in terms of tribology and provides clear advantages in formability.

  1. Use of hypereutectoid high-speed steel 11M5F for the production of cutting and cold-stamping tools in the Avtovaz Joint-Stock Company

    NASA Astrophysics Data System (ADS)

    Malakhov, V. V.; Yartsev, A. N.; Buyanskaya, T. A.; Matveev, S. V.; Berdnikova, L. N.

    1997-05-01

    The development of low-alloy high-speed steels that reduce the production cost of cutting tools and dies can present practical interest for plants and small enterprises manufacturing tools for their special purposes. The present paper gives the results of an investigation of hypereutectoid low-alloy high-speed steel 11M5F and a widely used steel of grade R6M5. The basic and technological properties of these steels are compared, and the results of industrial tests of cutting, thread-rolling, cold-stamping tools and tools for semihot deformation operating under various conditions are described.

  2. Cutting performance of alumina-based ceramic tools when machining high tensile steel

    SciTech Connect

    Li, X.S.; Low, I.M.; O`Conner, B.H.; Wager, J.G.; Perera, D.S.

    1993-12-31

    Three types of alumina-based ceramic tools SN60, AZ5000 (zirconia toughened), A65, HC2 (titanium carbide reinforced) and CC670 (silicon carbide whisker reinforced) were used for the evaluation of cutting performance when machining a high tensile steel (AISI 4340). Experimental studies were carried out at various cutting speeds (200--600 m/min), feeds (0.1--0.4 mm/rev) and depths of cut (0.5--2.0 mm), in dry conditions. The cutting performance of alumina-based ceramic tools was judged according to the cutting force produced during the process of machining, surface roughness of the workpiece and wear rate of the cutting inserts. A piezoelectric dynamometer was employed to measure the cutting forces. The flank wear was used to determine the tool-life of these inserts. The cutting performance of these alumina-based ceramic tools was analyzed and compared. The influence of cutting parameters (i. e. cutting speed, feed rate and depth of cut) on cutting performance is discussed.

  3. Structural properties of H13 tool steel parts produced with use of selective laser melting technology

    NASA Astrophysics Data System (ADS)

    Šafka, J.; Ackermann, M.; Voleský, L.

    2016-04-01

    This paper deals with establishing of building parameters for 1.2344 (H13) tool steel processed using Selective Laser Melting (SLM) technology with layer thickness of 50 µm. In the first part of the work, testing matrix of models in the form of a cube with chamfered edge were built under various building parameters such as laser scanning speed and laser power. Resulting models were subjected to set of tests including measurement of surface roughness, inspection of inner structure with aid of Light Optical Microscopy and Scanning Electron Microscopy and evaluation of micro-hardness. These tests helped us to evaluate an influence of changes in building strategy to the properties of the resulting model. In the second part of the work, mechanical properties of the H13 steel were examined. For this purpose, the set of samples in the form of “dog bone” were printed under three different alignments towards the building plate and tested on universal testing machine. Mechanical testing of the samples should then reveal if the different orientation and thus different layering of the material somehow influence its mechanical properties. For this type of material, the producer provides the parameters for layer thickness of 30 µm only. Thus, our 50 µm building strategy brings shortening of the building time which is valuable especially for large models. Results of mechanical tests show slight variation in mechanical properties for various alignment of the sample.

  4. Some aspects of machining cast Al-SiCp composites with conventional high speed steel and tungsten carbide tools

    NASA Astrophysics Data System (ADS)

    Narahari, P.; Pai, B. C.; Pillai, R. M.

    1999-10-01

    An attempt was made to evaluate machining of eutectic Al-Si (LM6) and hypoeutectic Al-Si (LM25) alloys reinforced with 10, 15, and 20% SiCp of two particle sizes using conventional high-speed steel (HSS) and tungsten carbide (WC) tools by varying cutting speed, feed, depth of cut, and environment. Machining of metal matrix composites (MMCs) is a difficult task using HSS and WC tools. The tool life of both these conventional tools was observed to decrease with increasing percentage and coarseness of SiCp in the composites. Tungsten carbide tools had a longer tool life than HSS under all the different conditions studied. Contrary to the known phenomenon of enhanced tool life in machining monolithic alloys with the use of cutting fluid, the tool life of WC/HSS tool in machining composites with cutting fluid was only 10 to 20% of that without cutting fluid.

  5. Carbide Precipitation During Tempering of a Tool Steel Subjected to Deep Cryogenic Treatment

    NASA Astrophysics Data System (ADS)

    Gavriljuk, V. G.; Sirosh, V. A.; Petrov, Yu. N.; Tyshchenko, A. I.; Theisen, W.; Kortmann, A.

    2014-05-01

    between the strain-induced transformation of the retained austenite and carbide precipitation during the wear can control the life of steel tools.

  6. Direct Metal Deposition of H13 Tool Steel on Copper Alloy Substrate: Parametric Investigation

    NASA Astrophysics Data System (ADS)

    Imran, M. Khalid; Masood, S. H.; Brandt, Milan

    2015-12-01

    Over the past decade, researchers have demonstrated interest in tribology and prototyping by the laser aided material deposition process. Laser aided direct metal deposition (DMD) enables the formation of a uniform clad by melting the powder to form desired component from metal powder materials. In this research H13 tool steel has been used to clad on a copper alloy substrate using DMD. The effects of laser parameters on the quality of DMD deposited clad have been investigated and acceptable processing parameters have been determined largely through trial-and-error approaches. The relationships between DMD process parameters and the product characteristics such as porosity, micro-cracks and microhardness have been analysed using scanning electron microscope (SEM), image analysis software (ImageJ) and microhardness tester. It has been found that DMD parameters such as laser power, powder mass flow rate, feed rate and focus size have an important role in clad quality and crack formation.

  7. Alloy design to control the size and morphology of niobium carbides in tool steels

    SciTech Connect

    Pereira, M.M.; Andrade, M.S. , Belo Horizonte, MG ); Guimaraes, J.R.C. )

    1989-09-01

    Controlling the size and the morphology of niobium carbides is crucial to develop a carbide volume fraction capable of significantly influencing the cutting/wear properties of tool steels and cast irons. The phase diagram suggests that by increasing the delta phase field, ferrite may be forced to precipitate preferentially to NbC. Hence, alloying with a strong ferritizer such as aluminum and/or silicon may result in more convenient microstructure when Nb %{gt}3. To check that possibility, as-cast microstructures were analyzed by optical and scanning electron microscopy. By combining additions of niobium and aluminum, it seems possible to control the size and the morphology of niobium carbides without necessarily resorting to more complex processes such as atomization and the like.

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

    NASA Technical Reports Server (NTRS)

    Bamberger, E. N.

    1973-01-01

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

  9. Semi-solid processing of high-chromium tool steel to obtain microstructures without carbide network

    NASA Astrophysics Data System (ADS)

    Jirková, H.; Aišman, D.; Rubešová, K.; Opatová, K.; Mašek, B.

    2017-02-01

    Treatment of high-alloy tool steels that involves transition to the semi-solid state can transform the sharp-edged primary carbides which usually form during solidification. These carbides severely impair toughness and are virtually impossible to eliminate by conventional treatment routes. Upon classical semi-solid processing which dissolves these carbides, the resulting microstructure consists of polyhedral and super-saturated austenite embedded in lamellar austenite-carbide network. This type of microstructure reflects in the mechanical properties, predominantly in material behaviour under tensile loading. Such a network, however, can be removed by appropriate thermomechanical treatment. In the present experiment, various procedures involving heating to the semi-solid state were tested on X210Cr12 tool steel. The feedstock was heated to the temperature range of 1220 – 1280 °C. The heating was followed by procedures involving either water quenching to the forming temperature, room temperature or temperature from the range from 500 °C to 1000 °C followed by reheating to the forming temperature. It was found that the development of the lamellar network strongly depends on the temperature of heating to semi-solid state. Thermomechanical treatment produced microstructures in which the matrix consisted of a mixture of polyhedral austenite grains and the M-A constituent. In addition, the initial lamellar eutectic network was partially or even completely melted and substituted with a mixture of very fine recrystallized austenite grains and precipitates of chromium carbides. Some fine M7C3 carbides were present in the austenitic-martensitic matrix as well. When appropriate processing parameters were chosen, very good mechanical properties were obtained, among them a hardness of 860 HV10.

  10. Process of vacuum hardening of cutting and sharpening tools of high-speed steels in belt furnaces

    NASA Astrophysics Data System (ADS)

    Tarasovi, A. N.

    1996-12-01

    The technical possibilities of vacuum elevator and bell furnaces commonly used for brazing and annealing precision parts in instrument-making and electronics can be widened. Small thin-blade tools of powder steels R6M5-P, 10R6M5-MP and "silver" steels R6M5, R6M5K5 with a minimum tolerance for sizing after hardening at a low cooling rate have high operational properties. The present paper is devoted to the process of heat treatment of special tools of the listed steels used to cut and shape ribbons, rods, and foils of alloys 36NKhTYu, 29NK, BrB2 in vacuum bcil furnaces under conditions of batch and small-batch production in electrical-engineering enterprises.

  11. Surface Microstructure and Properties of Pulsed Laser Micro Melted S7 Tool Steel

    NASA Astrophysics Data System (ADS)

    Morrow, Justin D.

    The objective of this work is to better understand the changes that occur in the surface microstructure and hardness due to pulsed laser micro melting (PLmuM) on AISI S7 tool steel and how these results change with the laser processing parameters. Pulsed laser micro polishing (PLmuP), using PLmuM on rough surfaces for smoothing, has been well studied at UW - Madison, but is still generally a small research area and previous work at UW - Madison as well as the bulk of related work from other universities and research institutes has focused on surface smoothing, not surface microstructure and properties. Therefore, the present work focuses on characterizing the effect of PLmuM on the surface microstructure transformations, hardness, and wear resistance in AISI S7 tool steel. An observational approach was taken to characterize the microstructure that is formed during PLmuM and evaluate the hardness and wear resistance of this final surface. Several experimental methods were used: The surface microstructure was evaluated using metallographic polishing and etching along with scanning electron microscopy (SEM) and x-ray diffraction (XRD). This work found that the microstructure after PLmuM is martensitic (lath martensite) and after overlapping to form a melted area, significant carbide precipitation can occur near the overlap regions. It was found that the size and prevalence of the carbides varies locally and carbides are coarser closer to the overlap region. The amount of carbide precipitation (tempering) was also found to depend on the laser parameters used. An XRD study showed that tempering could also be observed as a shifting of the martensite peak that correlated with hardness and tempering observed with SEM. The surface properties were also evaluated using nanoindentation and nanoscratch testing. These tests showed that the local tempering variation observed in the microstructure translated into local hardness variation with an inverse relationship between

  12. Friction stir spot welded joints of 409L stainless steels fabricated by a convex shoulder tool

    NASA Astrophysics Data System (ADS)

    Hossain, Md. Abu Mowazzem; Hasan, Md. Tariqul; Hong, Sung-Tae; Miles, Michael; Cho, Hoon-Hwe; Han, Heung Nam

    2013-11-01

    Spot joints of ferritic 409L stainless steel are successfully fabricated by friction stir spot welding (FSSW) using a convex shoulder tool. The welding process, microstructure and failure of the FSSW joint are investigated experimentally. During the FSSW process, the Z-force history shows significant variations depending on the contact phenomena between the tool and the joined sheets, while the Z-torque history shows a rather steady increase without pronounced changes in the trend until the initiation of dwelling. Electron back-scatter diffraction suggests that both continuous dynamic recrystallization and recovery occurred in the stir zone during the FSSW process. Observation of the FSSW joint that failed under the given lap shear load shows that the cracks, which are the result of the interfaces between the upper and lower sheets, propagated into the weld along the interfacial surfaces, after which a necking/shear failure occurred. Finally, the rupture of the joint, which was initiated by the necking/shear failure, propagated along the circumference of the weld.

  13. Evaluation of microstructure and mechanical properties in friction stir processed SKD61 tool steel

    SciTech Connect

    Chen, Y.C.; Nakata, K.

    2009-12-15

    A SKD61 tool steel was friction stir processed using a polycrystalline cubic boron nitride tool. Microstructure, tensile properties and wear characteristic were evaluated. Fine grains with a martensite structure were produced in the friction stir processed zone, which led to the increase of the microindentation hardness. The grains became finer when the heat input was lowered. The transverse tensile strength of the friction stir processed zone was equal to that of base metal and all the tensile specimens fractured at base metal zone. The wear width and depth of the friction stir processed zone at the load of 1.96 N were 339 {mu}m and 6 {mu}m, as compared to 888 {mu}m and 42 {mu}m of the base metal, decreased by 62% and 86%. Findings of the present study suggest that low heat input is an effective method to produce a friction stir processed zone composed of relatively fine grain martensitic structure with good tensile properties and wear characteristic.

  14. Acoustic Emission Detection of Macro-Cracks on Engraving Tool Steel Inserts during the Injection Molding Cycle Using PZT Sensors

    PubMed Central

    Svečko, Rajko; Kusić, Dragan; Kek, Tomaž; Sarjaš, Andrej; Hančič, Aleš; Grum, Janez

    2013-01-01

    This paper presents an improved monitoring system for the failure detection of engraving tool steel inserts during the injection molding cycle. This system uses acoustic emission PZT sensors mounted through acoustic waveguides on the engraving insert. We were thus able to clearly distinguish the defect through measured AE signals. Two engraving tool steel inserts were tested during the production of standard test specimens, each under the same processing conditions. By closely comparing the captured AE signals on both engraving inserts during the filling and packing stages, we were able to detect the presence of macro-cracks on one engraving insert. Gabor wavelet analysis was used for closer examination of the captured AE signals' peak amplitudes during the filling and packing stages. The obtained results revealed that such a system could be used successfully as an improved tool for monitoring the integrity of an injection molding process. PMID:23673677

  15. Ion-nitriding of the AISI M2 high speed tool steel and comparison of its mechanical properties with nitrided steels

    SciTech Connect

    Cimen, O.; Alnipak, B.

    1995-12-31

    In the past it was shown that plasma diffusion treatment of steels has several advantages over conventional processes such as gas or salt bath nitriding and nitrocarburizing. Plasma diffusion treatment allows close control of the process so that surface layers with defined microstructures and properties can be obtained. The amount of {gamma}{prime} and {epsilon} phase present can be easily controlled. In this paper, variation of surfaces hardness properties of AISI M2 high speed tool speed after ion nitriding treatments were investigated. The mechanical and electro-chemical advantages of the ion nitrided structures were compared with the other methods.

  16. SIMS evaluation of poly crystal boron nitride tool effect in thermo-mechanically affected zone of friction stir weld steels

    NASA Astrophysics Data System (ADS)

    Kim, JaeNam; Lee, SangUp; Kwun, HyoegDae; Shin, KwangSoo; Kang, ChangYong

    2014-11-01

    The effect of the poly crystal boron nitride (PCBN) tool in friction stir weld (FSW) steels was evaluated using the secondary ion mass spectroscopy (SIMS) technique. This study focused on the quantitative SIMS analysis of impurity boron through a resistive anode encoder (RAE) image. The RAE images were transformed retrospective depth profile by profiler. The relative sensitivity factors (RSFs) for boron varied heavily according to by the polarity of secondary voltage and matrix materials. The RAE images of cluster-polyatomic secondary ion species, 11B16O2, properly map the distribution of impurity boron in the thermo-mechanically affected zone (TMAZ) of FSW steels using negative secondary polarity 4.5 kV. A combination of cluster-polyatomic ion, 11B16O2 and 56Fe16O provided a good calibration curve by 3 SRMs with the least matrix effect. The boron concentrations of TMAZ in FSW steels were determined through the calibration curve by taking the corresponding boron concentration value (CB) of the intensity ratio (Ii/Im) from unknown samples. The new SIMS quantification technique of impurity boron from RAE images is found to be effective for a more quantitative understanding of the wear mechanism of the PCBN tool in TMAZ of FSW steels.

  17. Effect of Temperature on Microstructure, Corrosion Resistance, and Toughness of Salt Bath Nitrided Tool Steel

    NASA Astrophysics Data System (ADS)

    Fu, Hangtao; Zhang, Jin; Huang, Jinfeng; Lian, Yong; Zhang, Cheng

    2016-01-01

    In this study, a type of hot work tool steel was modified through salt bath nitriding for 4 h at 540 and 560 °C, and post-oxidation was subsequently performed. Surface and cross-sectional hardness test results revealed that the surface hardness increased after the treatment because of the formation of compound layers and diffusion zones. Microstructures and phase analyses showed that more homogeneous compound layers and Fe3O4-phase could be generated after treatment at 560 than at 540 °C. As a result, the corrosion potential was elevated, and the corrosion current density was clearly reduced. The thickness and porosity of the compound layer were also increased with the elevated nitriding temperature. Because of the nitrogen atom solution, XRD diffraction peaks broadened, and the position of the peaks shifted to a lower angle in different degrees at different depths, thus showing the same tendency as the hardness curves. Salt bath nitriding significantly deteriorated the impact toughness from 32.3 to 5.2 J.

  18. The Characteristics and Generating Mechanism of Large Precipitates in Ti-Containing H13 Tool Steel

    NASA Astrophysics Data System (ADS)

    Xie, You; Cheng, Guoguang; Chen, Lie; Zhang, Yandong; Yan, Qingzhong

    2017-02-01

    The characteristics of large precipitates in H13 tool steel with 0.015wt% Ti were studied. The result shows that three types of phases larger than 1 μm exist in the as-cast ingot, that is, (Ti, V) (C, N) type phase, (V, Mo, Cr)C type phase and sulfide. (Ti, V) (C, N) type phase could be further classified as the homogeneous Ti-rich one and the Ti-V-rich one in which Ti/V ratio gradually changes. (V, Mo, Cr)C type phase contains the V-rich one and the Mo-Cr-rich one. The compositional characteristics in all of them have little relation with the cutting position or cooling rate. The precipitating process could be well described through calculation by Thermo-Calc software. During solidification, the primary phase (Ti, V)(C, N) first starts to precipitate in the form of Ti-rich carbonitride. With the development of solidification, the ratio of Ti decreases and that of V increases. Then the primary phase Ti-V-rich (Ti, V)(C, N) and V-rich (V, Mo, Cr)C appears successively. Mo-Cr-rich (V, Mo, Cr)C phase does not precipitate until the solidification process reaches to the end. Sulfide precipitates before (V, Mo, Cr)C type phase and it could act as the nucleus of (V, Mo, Cr)C.

  19. Temperature and composition profile during double-track laser cladding of H13 tool steel

    NASA Astrophysics Data System (ADS)

    He, X.; Yu, G.; Mazumder, J.

    2010-01-01

    Multi-track laser cladding is now applied commercially in a range of industries such as automotive, mining and aerospace due to its diversified potential for material processing. The knowledge of temperature, velocity and composition distribution history is essential for a better understanding of the process and subsequent microstructure evolution and properties. Numerical simulation not only helps to understand the complex physical phenomena and underlying principles involved in this process, but it can also be used in the process prediction and system control. The double-track coaxial laser cladding with H13 tool steel powder injection is simulated using a comprehensive three-dimensional model, based on the mass, momentum, energy conservation and solute transport equation. Some important physical phenomena, such as heat transfer, phase changes, mass addition and fluid flow, are taken into account in the calculation. The physical properties for a mixture of solid and liquid phase are defined by treating it as a continuum media. The velocity of the laser beam during the transition between two tracks is considered. The evolution of temperature and composition of different monitoring locations is simulated.

  20. Microstructural Evolution during DPRM Process of Semisolid Ledeburitic D2 Tool Steel

    PubMed Central

    Mohammed, M. N.; Omar, M. Z.; Syarif, J.; Sajuri, Z.; Salleh, M. S.; Alhawari, K. S.

    2013-01-01

    Semisolid metal processing is a relatively new technology that offers several advantages over liquid processing and solid processing because of the unique behaviour and characteristic microstructure of metals in this state. With the aim of finding a minimum process chain for the manufacture of high-quality production at minimal cost for forming, the microstructural evolution of the ledeburitic AISI D2 tool steel in the semisolid state was studied experimentally. The potential of the direct partial remelting (DPRM) process for the production of AISI D2 with a uniform globular microstructure was revealed. The liquid fraction was determined using differential scanning calorimetry. The microstructures of the samples were investigated using an optical microscope and a scanning electron microscope equipped with an energy dispersive spectroscopy analyser, while X-ray phase analysis was performed to identify the phase evolution and the type of carbides. Mechanical characterisation was completed by hardness measurements. The typical microstructure after DPRM consists of metastable austenite which was located particularly in the globular grains (average grain size about 50 μm), while the remaining interspaces were filled by precipitated eutectic carbides on the grain boundaries and lamellar network. PMID:24223510

  1. Microstructure and Mechanical Properties of Laser Clad and Post-cladding Tempered AISI H13 Tool Steel

    NASA Astrophysics Data System (ADS)

    Telasang, Gururaj; Dutta Majumdar, Jyotsna; Wasekar, Nitin; Padmanabham, G.; Manna, Indranil

    2015-05-01

    This study reports a detailed investigation of the microstructure and mechanical properties (wear resistance and tensile strength) of hardened and tempered AISI H13 tool steel substrate following laser cladding with AISI H13 tool steel powder in as-clad and after post-cladding conventional bulk isothermal tempering [at 823 K (550 °C) for 2 hours] heat treatment. Laser cladding was carried out on AISI H13 tool steel substrate using a 6 kW continuous wave diode laser coupled with fiber delivering an energy density of 133 J/mm2 and equipped with a co-axial powder feeding nozzle capable of feeding powder at the rate of 13.3 × 10-3 g/mm2. Laser clad zone comprises martensite, retained austenite, and carbides, and measures an average hardness of 600 to 650 VHN. Subsequent isothermal tempering converted the microstructure into one with tempered martensite and uniform dispersion of carbides with a hardness of 550 to 650 VHN. Interestingly, laser cladding introduced residual compressive stress of 670 ± 15 MPa, which reduces to 580 ± 20 MPa following isothermal tempering. Micro-tensile testing with specimens machined from the clad zone across or transverse to cladding direction showed high strength but failure in brittle mode. On the other hand, similar testing with samples sectioned from the clad zone parallel or longitudinal to the direction of laser cladding prior to and after post-cladding tempering recorded lower strength but ductile failure with 4.7 and 8 pct elongation, respectively. Wear resistance of the laser surface clad and post-cladding tempered samples (evaluated by fretting wear testing) registered superior performance as compared to that of conventional hardened and tempered AISI H13 tool steel.

  2. Nanostructured Multilayer Composite Coatings on Ceramic Cutting Tools for Finishing Treatment of High-Hardness Quenched Steels

    NASA Astrophysics Data System (ADS)

    Vereshchaka, A. A.; Batako, A. D.; Sotova, E. S.; Vereshchaka, A. S.

    2016-01-01

    The functional role of nanostructured multilayer composite coatings (NMCC) deposited on the operating surfaces of replaceable faceted cutting inserts (CI) from cutting ceramics based on aluminum oxides with additives of titanium carbides is studied. It is shown that the developed NMCC not only raise substantially the endurance of the ceramic tools under high-speed dry treatment of quenched steels but also improve the quality and accuracy of processing of the parts and the ecological parameters of the cutting process.

  3. LASER APPLICATIONS AND OTHER TOPICS IN LASER TECHNOLOGY: Combination of laser quenching and tempering for hardening tool steels

    NASA Astrophysics Data System (ADS)

    Gureev, D. M.; Mednikov, S. I.

    1988-08-01

    A study was made of the influence of laser quenching and tempering on the structural phase composition and hardness of surface layers of KhVG and ÉP657 (R12M3F2K8) tool steels subjected to volume quenching and tempering. It was found to be advisable, in addition to performing laser quenching, to carry out laser tempering before and after in order to take into account the initial state of the material and to obtain stable results on improvements in the wear resistance of cutting and stamping tools.

  4. Wear and Adhesive Failure of Al2O3 Powder Coating Sprayed onto AISI H13 Tool Steel Substrate

    NASA Astrophysics Data System (ADS)

    Amanov, Auezhan; Pyun, Young-Sik

    2016-07-01

    In this study, an alumina (Al2O3) ceramic powder was sprayed onto an AISI H13 hot-work tool steel substrate that was subjected to sanding and ultrasonic nanocrystalline surface modification (UNSM) treatment processes. The significance of the UNSM technique on the adhesive failure of the Al2O3 coating and on the hardness of the substrate was investigated. The adhesive failure of the coating sprayed onto sanded and UNSM-treated substrates was investigated by a micro-scratch tester at an incremental load. It was found, based on the obtained results, that the coating sprayed onto the UNSM-treated substrate exhibited a better resistance to adhesive failure in comparison with that of the coating sprayed onto the sanded substrate. Dry friction and wear property of the coatings sprayed onto the sanded and UNSM-treated substrates were assessed by means of a ball-on-disk tribometer against an AISI 52100 steel ball. It was demonstrated that the UNSM technique controllably improved the adhesive failure of the Al2O3 coating, where the critical load was improved by about 31%. Thus, it is expected that the application of the UNSM technique to an AISI H13 tool steel substrate prior to coating may delay the adhesive failure and improve the sticking between the coating and the substrate thanks to the modified and hardened surface.

  5. Finite Element Modelling of the effect of tool rake angle on tool temperature and cutting force during high speed machining of AISI 4340 steel

    NASA Astrophysics Data System (ADS)

    Sulaiman, S.; Roshan, A.; Ariffin, M. K. A.

    2013-12-01

    In this paper, a Finite Element Method (FEM) based on the ABAQUS explicit software which involves Johnson-Cook material model was used to simulate cutting force and tool temperature during high speed machining (HSM) of AISI 4340 steel. In this simulation work, a tool rake angle ranging from 0° to 20° and a range of cutting speeds between 300 to 550 m/min was investigated. The purpose of this simulation analysis was to find optimum tool rake angle where cutting force is smallest as well as tool temperature is lowest during high speed machining. It was found that cutting forces to have a decreasing trend as rake angle increased to positive direction. The optimum rake angle observed between 10° and 18° due to decrease of cutting force as 20% for all simulated cutting speeds. In addition, increasing cutting tool rake angle over its optimum value had negative influence on tool's performance and led to an increase in cutting temperature. The results give a better understanding and recognition of the cutting tool design for high speed machining processes.

  6. An investigation into the effects of conventional heat treatments on mechanical characteristics of new hot working tool steel

    NASA Astrophysics Data System (ADS)

    Fares, M. L.; Athmani, M.; Khelfaoui, Y.; Khettache, A.

    2012-02-01

    The effects of conventional heat treatments, i.e. quenching and tempering, on the mechanical characteristics of non standard hot work tool steel, close to either AISI-H11/H13 are investigated. The major elemental composition differences are in carbon, silicon and vanadium. The objective of the carried heat treatments is to obtain an efficient tool performance in terms of hardness, wear resistance and mechanical strength. Experimental results allow an explanation of the surface properties depending mainly on both chemical composition and optimised preheating parameters. After austenitizing at 1050 °C for 15 min, the as-quenched steel in oil bath exhibited the fully martensitic structure (without bainite) connected to a small fraction of retained austenite and complex carbides mainly of M23C6 type. Twice tempering at 500 °C and 600 °C resulted in initiating the precipitation processes and the secondary hardness effect. As a result, carbide content amounted to 3% while the retained austenite content decreased to 0%. Accordingly, the required mechanical properties in terms of hardness and wear are fulfilled and are adequately favourable in handling both shocks and pressures for the expected tool life. Induced microstructures are revealed using optical and scanning electron microscopes. Phase compositions are assessed by means of X-ray diffraction technique while mechanical characteristics are investigated based on hardness and abrasive wear standard tests.

  7. Parametric Optimization of Wire Electrical Discharge Machining of Powder Metallurgical Cold Worked Tool Steel using Taguchi Method

    NASA Astrophysics Data System (ADS)

    Sudhakara, Dara; Prasanthi, Guvvala

    2016-08-01

    Wire Cut EDM is an unconventional machining process used to build components of complex shape. The current work mainly deals with optimization of surface roughness while machining P/M CW TOOL STEEL by Wire cut EDM using Taguchi method. The process parameters of the Wire Cut EDM is ON, OFF, IP, SV, WT, and WP. L27 OA is used for to design of the experiments for conducting experimentation. In order to find out the effecting parameters on the surface roughness, ANOVA analysis is engaged. The optimum levels for getting minimum surface roughness is ON = 108 µs, OFF = 63 µs, IP = 11 A, SV = 68 V and WT = 8 g.

  8. Influence of minimum quantity lubrication parameters on tool wear and surface roughness in milling of forged steel

    NASA Astrophysics Data System (ADS)

    Yan, Lutao; Yuan, Songmei; Liu, Qiang

    2012-05-01

    The minimum quantity of lubrication (MQL) technique is becoming increasingly more popular due to the safety of environment. Moreover, MQL technique not only leads to economical benefits by way of saving lubricant costs but also presents better machinability. However, the effect of MQL parameters on machining is still not clear, which needs to be overcome. In this paper, the effect of different modes of lubrication, i.e., conventional way using flushing, dry cutting and using the minimum quantity lubrication (MQL) technique on the machinability in end milling of a forged steel (50CrMnMo), is investigated. The influence of MQL parameters on tool wear and surface roughness is also discussed. MQL parameters include nozzle direction in relation to feed direction, nozzle elevation angle, distance from the nozzle tip to the cutting zone, lubricant flow rate and air pressure. The investigation results show that MQL technique lowers the tool wear and surface roughness values compared with that of conventional flood cutting fluid supply and dry cutting conditions. Based on the investigations of chip morphology and color, MQL technique reduces the cutting temperature to some extent. The relative nozzle-feed position at 120°, the angle elevation of 60° and distance from nozzle tip to cutting zone at 20 mm provide the prolonged tool life and reduced surface roughness values. This fact is due to the oil mists can penetrate in the inner zones of the tool edges in a very efficient way. Improvement in tool life and surface finish could be achieved utilizing higher oil flow rate and higher compressed air pressure. Moreover, oil flow rate increased from 43.8 mL/h to 58.4 mL/h leads to a small decrease of flank wear, but it is not very significant. The results obtained in this paper can be used to determine optimal conditions for milling of forged steel under MQL conditions.

  9. Application of Magnetic Kinds of Nondestructive Inspection to Parts From Die Tool Steels

    NASA Astrophysics Data System (ADS)

    Kornilova, A. V.; Selishchev, A. I.; Idarmachev, I. M.

    2016-01-01

    Possibilities of control of the level of accumulated damage in dies for cold and hot forming as a function of the coercivity are considered. The coercivity of the material of dies for hot forging and cold stamping is studied. Formulas are obtained for determining the coercivity in steels for hot die forging in the state as delivered.

  10. Determination of the Microstructure of Powder Tool Steels by Different Etching Techniques

    NASA Astrophysics Data System (ADS)

    Atapek, Ş. H.; Polat, Ş.; Gümüş, S.; Erişir, E.; Altuğ, G. S.

    2014-07-01

    The microstructure of three powder high-speed steels is studied in quenched and tempered conditions by methods of light and scanning electron microscopy. Several types of carbides with different morphology are detected by using various methods of etching of specimens. The composition of the carbide phases is determined by the method of energy dispersive local analysis.

  11. Assessment of Retained Austenite in AISI D2 Tool Steel Using Magnetic Hysteresis and Barkhausen Noise Parameters

    NASA Astrophysics Data System (ADS)

    Kahrobaee, Saeed; Kashefi, Mehrdad

    2015-03-01

    Inaccurate heat treatment process could result in excessive amount of retained austenite, which degrades the mechanical properties, like strength, wear resistance, and hardness of cold work tool steel parts. Thus, to control the mechanical properties, quantitative measurement of the retained austenite is a critical step in optimizing the heat-treating parameters. X-ray diffraction method is the most frequently used technique for this purpose. This technique is, however, destructive and time consuming. Furthermore, it is not applicable to 100% quality inspection of industrial parts. In the present paper, the influence of austenitizing temperature on the retained austenite content and hardness of AISI D2 tool steel has been studied. Additionally, nondestructive magnetic hysteresis parameters of the samples including coercivity, magnetic saturation, and maximum differential permeability as well as their magnetic Barkhausen noise features (RMS peak voltage and peak position) have been investigated. The results revealed direct relations between magnetic saturation, differential permeability, and MBN peak amplitude with increasing austenitizing temperature due to the retained austenite formation. Besides, both parameters of coercivity and peak position had an inverse correlation with the retained austenite fraction.

  12. Applications of ArcelorMittal Thermodynamic Computation Tools to Steel Production

    NASA Astrophysics Data System (ADS)

    Lehmann, Jean

    CEQCSI is an ArcelorMittal in-house built thermodynamic equilibrium calculation software which is used both at high temperatures typically for slag-metal reactions but also at "low" temperatures to study solid phase transformations and precipitation in solid steel. It has been built to accommodate different thermodynamic models for slag (the Cell model, the Generalized Central Atom model - product of a collaboration between ArcelorMittal Global R&D Maizieres and CSIRO Melbourne), for steel (sublattice model, Wagner Interaction Parameter Formalism) as well as for oxide, sulfide, carbide… solid solutions. Examples of application concern Si, Mn, S slag-metal equilibrium in Blast-Furnace, P partition in BOF slags, slag-metal equilibrium for flat and long products in ladle… Apart from data relating to mass transfer between different phases at equilibrium, CEQCSI proposes several estimates for slag viscosities with among them one delivered by a new model based on the Generalized Central Atom thermodynamic model for slags. CEQCSI conception allows also handling some kinetic problems such as desulfurization in ladle or slag/metal reaction in mold.

  13. Formation of laser-induced periodic surface structures (LIPSS) on tool steel by multiple picosecond laser pulses of different polarizations

    NASA Astrophysics Data System (ADS)

    Gregorčič, Peter; Sedlaček, Marko; Podgornik, Bojan; Reif, Jürgen

    2016-11-01

    Laser-induced periodic surface structures (LIPSS) are produced on cold work tool steel by irradiation with a low number of picosecond laser pulses. As expected, the ripples, with a period of about 90% of the laser wavelength, are oriented perpendicular to the laser polarization. Subsequent irradiation with the polarization rotated by 45° or 90° results in a corresponding rotation of the ripples. This is visible already with the first pulse and becomes almost complete - erasing the previous orientation - after as few as three pulses. The phenomenon is not only observed for single-spot irradiation but also for writing long coherent traces. The experimental results strongly defy the role of surface plasmon-polaritons as the predominant key to LIPSS formation.

  14. EFFECTS OF LASER RADIATION ON MATTER. LASER PLASMA: Laser—ultrasonic formation of melts of high-speed tool steels

    NASA Astrophysics Data System (ADS)

    Gureev, D. M.

    1994-09-01

    A study was made of the influence of ultrasonic vibrations on the processes of heat and mass transfer, and of structure formation during ultrafast crystallisation of laser melts of T1 high-speed tool steel. Acoustic flows which appeared in laser melts effectively smoothed out the temperature inhomogeneities and flattened the relief of the molten surface even when the laser radiation acted for just ~1 ms. The transformation of the mechanical energy of ultrasonic vibrations into heat increased the depth of the laser melt baths and suppressed crack formation. The observed changes in the structural and phase composition appeared as a change in the microhardness of the solidified laser melts. The geometry of coupling of ultrasound into a laser melt influenced the changes in the microhardness, suggesting a need for a more detailed analysis of the structure formation processes in the course of ultrafast crystallisation of laser melts in an ultrasonic field.

  15. Introducing a new optimization tool for femtosecond laser-induced surface texturing on titanium, stainless steel, aluminum and copper

    NASA Astrophysics Data System (ADS)

    Ahmmed, K. M. Tanvir; Ling, Edwin Jee Yang; Servio, Phillip; Kietzig, Anne-Marie

    2015-03-01

    The surface micro- and nano-scale features produced by femtosecond laser irradiation on titanium, stainless steel, aluminum and copper are reported in this work. Each observed surface microstructure, which was fabricated from a particular combination of four adjustable parameters, can be characterized by the fluence and pulses-per-spot (F-PPS) and accumulated fluence profile (AFP) models. By performing a wide screening of the experimental space, we have successfully mapped the evolution of microstructures as a function of two variables per model. We have also shown that these two models, in conjunction with one another and the data that we have presented, can be used as an optimization tool for scientists and engineers to quickly fine-tune the laser processing settings necessary for a desired surface topography. In addition, the electron-phonon coupling strength and thermal conductivity have been identified as the material properties that have the largest influence over the achievable surface patterns on metallic substrates.

  16. Effect of Laser Beam Alloying Strategies on the Metallurgical and Mechanical Properties of Hot Forming Tool Steels

    NASA Astrophysics Data System (ADS)

    Hofmann, Konstantin; Neubauer, Franziska; Holzer, Matthias; Mann, Vincent; Hugger, Florian; Roth, Stephan; Schmidt, Michael

    In terms of increasing lightweight designs of car body parts, the machining of high strength steels in hot stamping processes becomes of particular interest. Due to high process forces at hot stamping, the surface of such tools in the area of maximal stress is subject wear, which necessitate some local increase of microhardness to enhance the mechanical performance. Especially laser beam alloying using filler wire and beam oscillation is some suitable method to modify the mechanical properties of tool surfaces to emcompass some continuous martensitic structure, featuring a certain microhardness. Nevertheless the thermal energy input during laser beam alloying induces tempering in the heat affected zone and reduces the hardness. This paper discusses the influence of alloying strategies on the thermal energy input and the resulting metallurgical structure of modified tool surfaces. Also the cooling behavior of alloyed lines for different energy inputs per unit length is of interest. Therefore, the metallurgical microstructure is analyzed regarding microhardness as well as formation of carbides. Furthermore, a numerical thermal simulation is developed to investigate the temperature profile in the heat affected zone of the specimen. These investigations permit the control of the spatiotemporal energy input to avoid tempering of the microstructure.

  17. Effect of cutting parameters on sustainable machining performance of coated carbide tool in dry turning process of stainless steel 316

    NASA Astrophysics Data System (ADS)

    Bagaber, Salem A.; Yusoff, Ahmed Razlan

    2017-04-01

    The manufacturing industry aims to produce many products of high quality with relatively less cost and time. Different cutting parameters affect the machining performance of surface roughness, cutting force, and material removal rate. Nevertheless, a few studies reported on the effects of sustainable factors such as power consumed, cycle time during machining, and tool life on the dry turning of AISI 316. The present study aims to evaluate the machining performance of coated carbide in the machining of hard steel AISI 316 under the dry turning process. The influence of cutting parameters of cutting speed, feed rate, and depth of cut with their five (5) levels is established by a central composite design. Highly significant parameters were determined by analysis of variance (ANOVA), and the main effects of power consumed and time during machining, surface roughness, and tool wear were observed. Results showed that the cutting speed was proportional to power consumption and tool wear. Meanwhile, insignificant to surface roughness, feed rate most significantly affected surface roughness and power consumption followed by depth of cut.

  18. Interface bonding of NiCrAlY coating on laser modified H13 tool steel surface

    NASA Astrophysics Data System (ADS)

    Reza, M. S.; Aqida, S. N.; Ismail, I.

    2016-06-01

    Bonding strength of thermal spray coatings depends on the interfacial adhesion between bond coat and substrate material. In this paper, NiCrAlY (Ni-164/211 Ni22 %Cr10 %Al1.0 %Y) coatings were developed on laser modified H13 tool steel surface using atmospheric plasma spray (APS). Different laser peak power, P p, and duty cycle, DC, were investigated in order to improve the mechanical properties of H13 tool steel surface. The APS spraying parameters setting for coatings were set constant. The coating microstructure near the interface was analyzed using IM7000 inverted optical microscope. Interface bonding of NiCrAlY was investigated by interfacial indentation test (IIT) method using MMT-X7 Matsuzawa Hardness Tester Machine with Vickers indenter. Diffusion of atoms along NiCrAlY coating, laser modified and substrate layers was investigated by energy-dispersive X-ray spectroscopy (EDXS) using Hitachi Tabletop Microscope TM3030 Plus. Based on IIT method results, average interfacial toughness, K avg, for reference sample was 2.15 MPa m1/2 compared to sample L1 range of K avg from 6.02 to 6.96 MPa m1/2 and sample L2 range of K avg from 2.47 to 3.46 MPa m1/2. Hence, according to K avg, sample L1 has the highest interface bonding and is being laser modified at lower laser peak power, P p, and higher duty cycle, DC, prior to coating. The EDXS analysis indicated the presence of Fe in the NiCrAlY coating layer and increased Ni and Cr composition in the laser modified layer. Atomic diffusion occurred in both coating and laser modified layers involved in Fe, Ni and Cr elements. These findings introduce enhancement of coating system by substrate surface modification to allow atomic diffusion.

  19. Why dried blood spots are an ideal tool for CYP1A2 phenotyping.

    PubMed

    De Kesel, Pieter M M; Lambert, Willy E; Stove, Christophe P

    2014-08-01

    Dried blood spot (DBS) sampling has gained wide interest in bioanalysis during the last decade and has already been successfully applied in pharmacokinetic and phenotyping studies. However, all of the available phenotyping studies used small datasets and did not include a systematic evaluation of DBS-specific parameters. The latter is important since several of these factors still challenge the breakthrough of DBS in routine practice. In this study, caffeine and paraxanthine are determined in capillary DBS, venous DBS, whole blood and plasma for cytochrome P450 (CYP) 1A2 phenotyping. The aim of this study was to explore the usefulness of DBS as a tool for CYP1A2 phenotyping. A CYP1A2 phenotyping study was conducted in 73 healthy volunteers who received a 150 mg oral dose of caffeine. Six hours post-administration, caffeine and paraxanthine concentrations and paraxanthine:caffeine molar concentration ratios, i.e., the actual CYP1A2 phenotyping indices, were determined in capillary DBS (obtained by non-volumetric application, direct from the fingertip), venous DBS, whole blood, and plasma. Furthermore, the impact of DBS-specific parameters, including hematocrit, volume spotted, and punch location, was evaluated. Concentrations of caffeine and paraxanthine in capillary DBS were, respectively, on average 12.7 and 13.8% lower than those in venous DBS and 31.5 and 33.1% lower than those in plasma. While these differences were statistically significant (p < 0.001), no significant difference was observed between the paraxanthine:caffeine molar ratios in the distinct evaluated matrices (p ≥ 0.053). This ratio also alleviated the impact of hematocrit and volume spotted. Using the largest DBS-based phenotyping study to date, we have demonstrated that CYP1A2 phenotyping in capillary DBS is a valid and convenient alternative for the classical plasma-based approach. Additionally, we have provided an objective basis as to why DBS are an ideal tool for CYP1A2 phenotyping.

  20. Microstructure and Mechanical Properties of Spray-Formed H13 Steel Tooling

    SciTech Connect

    Yaojun Lin; Kevin M. McHugh; Young-Soo Park; Yizhang Zhou; Enrique J. Lavernia

    2005-02-01

    This paper presents results on the microstructure and hardness of spray-formed H13 (Fe-0.40C-5.00Cr-1.10V-1.30Mo (wt%)) tooling. There is very low porosity in both as-spray formed samples and aged samples. The microstructure in the as-spray-formed sample is characterized by primary carbides, acicular lower bainite, and a small amount of martensite and of retained austenite. Spray formed and aged tooling H13 has higher hardness values than those of H13 in conventional tooling. The experimental results of microstructures and hardness are rationalized on the basis of numerical analysis of cooling during processing of spray-formed tooling.

  1. Tool life and cutting speed for the maximum productivity at the drilling of the stainless steel X22CrMoV12-1

    NASA Astrophysics Data System (ADS)

    Vlase, A.; Blăjină, O.; Iacob, M.; Darie, V.

    2015-11-01

    Two addressed issues in the research regarding the cutting machinability, establishing of the optimum cutting processing conditions and the optimum cutting regime, do not yet have sufficient data for solving. For this reason, in the paper it is proposed the optimization of the tool life and the cutting speed at the drilling of a certain stainless steel in terms of the maximum productivity. For this purpose, a nonlinear programming mathematical model to maximize the productivity at the drilling of the steel is developed in the paper. The optimum cutting tool life and the associated cutting tool speed are obtained by solving the numerical mathematical model. Using this proposed model allows increasing the accuracy in the prediction of the productivity for the drilling of a certain stainless steel and getting the optimum tool life and the optimum cutting speed for the maximum productivity. The results presented in this paper can be used in the production activity, in order to increase the productivity of the stainless steels machining. Also new research directions for the specialists in this interested field may come off from this paper.

  2. Effect of biomimetic coupling units' morphologies on rolling contact fatigue wear resistance of steel from machine tool rolling tracks

    NASA Astrophysics Data System (ADS)

    Yang, Wanshi; Zhou, Hong; Sun, Liang; Wang, Chuanwei; Chen, Zhikai

    2014-04-01

    The rolling contact fatigue wear resistance plays an important role on ensuring machining precision of machine tool using rolling tracks. Bio-inspired wearable surfaces with the alternated hardness were prepared on the specimen of steel material from machine tool rolling tracks by biomimetic coupling laser remelting method to imitate biological coupling principle. The microstructures and micromorphologies of bionic units in different sizes were characterized by optical microscope. The specimens with bionic units in different sizes and distributions were tested for rolling contact fatigue wear resistance. Combining the finite element analysis and the results of wear tests, a discussion on rolling contact fatigue wear was had. The specimens with bionic units had better rolling contact fatigue wear resistance than the untreated one, while the specimens with bionic units in the alternative depth's distributions present a better rolling contact fatigue wear resistance than the ones with bionic units in the single depth's distribution. It attributed to the alternative distribution made further improvement on the dispersion of depth of stress concentration.

  3. Microstructural characterization of WC-TiC-Co cutting tools during high-speed machining of P20 mold steel

    SciTech Connect

    Farhat, Z.N

    2003-10-15

    The wear behavior of tungsten carbide (WC)-TiC-Co cutting tools during cutting P20 tool steel was investigated. Orthogonal cutting tests were performed on a CNC lathe using five speeds, namely, 60, 120, 240, 380 and 600 m/min. Wear, as the width of the wear land, was monitored at five time intervals. Wear characterization of the rake and the flank surfaces as well as the collected chips was performed using scanning electron microscopy (SEM), backscattered electron imaging and energy-dispersive X-ray analysis (EDX). Microhardness of collected chips was also performed to monitor strain hardening effects during cutting. Two dominant wear mechanisms were identified: at high speed (380-600 m/min), wear was found to occur by a melt wear mechanism; at low speed (60-120 m/min), adhesion (built-up edge) followed by delamination was found to be the cause of wear damage. It was also found that deformation in the chips occurred by localized shear deformation.

  4. UPIOM: a new tool of MFA and its application to the flow of iron and steel associated with car production.

    PubMed

    Nakamura, Shinichiro; Kondo, Yasushi; Matsubae, Kazuyo; Nakajima, Kenichi; Nagasaka, Tetsuya

    2011-02-01

    Identification of the flow of materials and substances associated with a product system provides useful information for Life Cycle Analysis (LCA), and contributes to extending the scope of complementarity between LCA and Materials Flow Analysis/Substances Flow Analysis (MFA/SFA), the two major tools of industrial ecology. This paper proposes a new methodology based on input-output analysis for identifying the physical input-output flow of individual materials that is associated with the production of a unit of given product, the unit physical input-output by materials (UPIOM). While the Sankey diagram has been a standard tool for the visualization of MFA/SFA, with an increase in the complexity of the flows under consideration, which will be the case when economy-wide intersectoral flows of materials are involved, the Sankey diagram may become too complex for effective visualization. An alternative way to visually represent material flows is proposed which makes use of triangulation of the flow matrix based on degrees of fabrication. The proposed methodology is applied to the flow of pig iron and iron and steel scrap that are associated with the production of a passenger car in Japan. Its usefulness to identify a specific MFA pattern from the original IO table is demonstrated.

  5. Computer simulation of the relationship between selected properties of laser remelted tool steel surface layer

    NASA Astrophysics Data System (ADS)

    Bonek, Mirosław; Śliwa, Agata; Mikuła, Jarosław

    2016-12-01

    Investigations >The language in this paper has been slightly changed. Please check for clarity of thought, and that the meaning is still correct, and amend if necessary.include Finite Element Method simulation model of remelting of PMHSS6-5-3 high-speed steel surface layer using the high power diode laser (HPDL). The Finite Element Method computations were performed using ANSYS software. The scope of FEM simulation was determination of temperature distribution during laser alloying process at various process configurations regarding the laser beam power and method of powder deposition, as pre-coated past or surface with machined grooves. The Finite Element Method simulation was performed on five different 3-dimensional models. The model assumed nonlinear change of thermal conductivity, specific heat and density that were depended on temperature. The heating process was realized as heat flux corresponding to laser beam power of 1.4, 1.7 and 2.1 kW. Latent heat effects are considered during solidification. The molten pool is composed of the same material as the substrate and there is no chemical reaction. The absorptivity of laser energy was dependent on the simulated materials properties and their surface condition. The Finite Element Method simulation allows specifying the heat affected zone and the temperature distribution in the sample as a function of time and thus allows the estimation of the structural changes taking place during laser remelting process. The simulation was applied to determine the shape of molten pool and the penetration depth of remelted surface. Simulated penetration depth and molten pool profile have a good match with the experimental results. The depth values obtained in simulation are very close to experimental data. Regarding the shape of molten pool, the little differences have been noted. The heat flux input considered in simulation is only part of the mechanism for heating; thus, the final shape of solidified molten pool will depend

  6. Identification of Tool Wear when Machining of Austenitic Steels and Titatium by Miniature Machining

    NASA Astrophysics Data System (ADS)

    Pilc, Jozef; Kameník, Roman; Varga, Daniel; Martinček, Juraj; Sadilek, Marek

    2016-12-01

    Application of miniature machining is currently rapidly increasing mainly in biomedical industry and machining of hard-to-machine materials. Machinability of materials with increased level of toughness depends on factors that are important in the final state of surface integrity. Because of this, it is necessary to achieve high precision (varying in microns) in miniature machining. If we want to guarantee machining high precision, it is necessary to analyse tool wear intensity in direct interaction with given machined materials. During long-term cutting process, different cutting wedge deformations occur, leading in most cases to a rapid wear and destruction of the cutting wedge. This article deal with experimental monitoring of tool wear intensity during miniature machining.

  7. Research of Tool Durability in Surface Plastic Deformation Processing by Burnishing of Steel Without Metalworking Fluids

    NASA Astrophysics Data System (ADS)

    Grigoriev, S. N.; Bobrovskij, N. M.; Melnikov, P. A.; Bobrovskij, I. N.

    2017-05-01

    Modern vector of development of machining technologies aimed at the transition to environmentally safe technologies - “green” technologies. The concept of “green technology” includes a set of signs of knowledge intended for practical use (“technology”). One of the ways to improve the quality of production is the use of surface plastic deformation (SPD) processing methods. The advantage of the SPD is a capability to combine effects of finishing and strengthening treatment. The SPD processing can replace operations: fine turning, grinding or polishing. The SPD is a forceful contact impact of indentor on workpiece’s surface in condition of their relative motion. It is difficult to implement the core technology of the SPD (burnishing, roller burnishing, etc.) while maintaining core technological advantages without the use of lubricating and cooling technology (metalworking fluids, MWF). The “green” SPD technology was developed by the authors for dry processing and has not such shortcomings. When processing with SPD without use of MWF requirements for tool’s durability is most significant, especially in the conditions of mass production. It is important to determine the period of durability of tool at the design stage of the technological process with the purpose of wastage preventing. This paper represents the results of durability research of natural and synthetic diamonds (polycrystalline diamond - ASPK) as well as precision of polycrystalline superabrasive tools made of dense boron nitride (DBN) during SPD processing without application of MWF.

  8. Structure Integral Transform Versus Radon Transform: A 2D Mathematical Tool for Invariant Shape Recognition.

    PubMed

    Wang, Bin; Gao, Yongsheng

    2016-12-01

    In this paper, we present a novel mathematical tool, Structure Integral Transform (SIT), for invariant shape description and recognition. Different from the Radon Transform (RT), which integrates the shape image function over a 1D line in the image plane, the proposed SIT builds upon two orthogonal integrals over a 2D K -cross dissecting structure spanning across all rotation angles by which the shape regions are bisected in each integral. The proposed SIT brings the following advantages over the RT: 1) it has the extra function of describing the interior structural relationship within the shape which provides a more powerful discriminative ability for shape recognition; 2) the shape regions are dissected by the K -cross in a coarse to fine hierarchical order that can characterize the shape in a better spatial organization scanning from the center to the periphery; and 3) it is easier to build a completely invariant shape descriptor. The experimental results of applying SIT to shape recognition demonstrate its superior performance over the well-known Radon transform, and the well-known shape contexts and the polar harmonic transforms.

  9. Influence of pre-heating on the surface modification of powder-metallurgy processed cold-work tool steel during laser surface melting

    NASA Astrophysics Data System (ADS)

    Šturm, Roman; Štefanikova, Maria; Steiner Petrovič, Darja

    2015-01-01

    In this study we determine the optimal parameters for surface modification using the laser surface melting of powder-metallurgy processed, vanadium-rich, cold-work tool steel. A combination of steel pre-heating, laser surface melting and a subsequent heat treatment creates a hardened and morphologically modified surface of the selected high-alloy tool steel. The pre-heating of the steel prior to the laser surface melting ensures a crack- and pore-free modified surface. Using a pre-heating temperature of 350 °C, the extremely fine microstructure, which typically evolves during the laser-melting, became slightly coarser and the volume fraction of retained austenite was reduced. In the laser-melted layer the highest values of microhardness were achieved in the specimens where a subsequent heat treatment at 550 °C was applied. The performed thermodynamic calculations were able to provide a very valuable assessment of the liquidus temperature and, especially, a prediction of the chemical composition as well as the precipitation and dissolution sequence for the carbides.

  10. Preservation of Geometrical Integrity of Supersolidus-Liquid-Phase-Sintered SKD11 Tool Steels Prepared with Powder Injection Molding

    NASA Astrophysics Data System (ADS)

    Chuang, K. H.; Hwang, K. S.

    2011-07-01

    The powder injection molded SKD11 tool steels often manifest shape retention problems during supersolidus liquid phase sintering due to the difficulties in controlling the amount of liquid phase. The typical temperature range for the sintering of SKD11 is only 10 K, between 1503 and 1513 K (1230 and 1240 °C), and this narrow sintering range demands a special furnace with very uniform temperature distribution. Through the addition of carbides, in particular TiC, this problem is resolved by enlarging the liquid + γ + carbide region in the phase diagram and by impeding the grain growth with the carbides. The resulting sintering window is broadened to 40 K, between 1513 and 1553 K (1240 and 1280 °C). The relevant mechanisms on the improvement of shape retention are discussed with a focus on the effect of carbide addition on the changes in the phase diagram and the microstructure. A guideline for the selection of effective carbides is also proposed based on the experimental results and the phase diagram analyses.

  11. The damage of the cutting tools out of carbide metallic during the turning of a soaked and not hardened steel XC38

    NASA Astrophysics Data System (ADS)

    Seghouani, M.; Tafraoui, A.; Lebaili, S.

    2012-02-01

    The purpose of this study widened knowledge on the use of the cutting tools out of metal carbide and to define of it the influence of the elements of the mode of cut on the behaviour of these tools during the machining of treated steel XC38 and untreated. This work aims at evolution determined in experiments of the wear of a cutting tool out of metal carbide with plate reported of P30 nuance for an operation of slide-lathing in turning on soaked and not hardened steel XC38 test-tubes. This research is based on the model of Taylor to determine the lifespan of the cutting tool according to the various parameters of cut, like the cutting speed Vc, the advance of cut a, the depth of cutting P. In order to express the operational limits of the tool for slide-lathing in a preventive way. The model makes it possible to determine the time of change of the tool and to regard it as constraint for the respect of the roughness of the work piece during a work of series in conventional machining.

  12. Modern trends in increasing the quality of the steels intended for cutting and metal-working tools: I. Improvement of granule metallurgy processes

    NASA Astrophysics Data System (ADS)

    Belyanchikov, L. N.

    2008-12-01

    The following new technological processes for producing fine gas-atomized powders of tool and high-speed steels with a low content of nonmetallic inclusions are considered: the process designed by Böhler Uddeholm Powder Technology (Austria) and processes involving a heated gas. In the former process, a metal is poured from a ladle with electroslag heating, and the atomizing unit consists of three injectors. A new process of producing tools from fine powders by three-dimensional printing, i.e., so-called 3D-printing, is described.

  13. The material performance of HSS (high speed steel) tools and its relation with chemical composition and carbide distribution

    NASA Astrophysics Data System (ADS)

    Darmawan, B.; Kusman, M.; Hamdani, R. A.

    2016-04-01

    The study aims to compare the performance of two types of material HSS (High Speed Steel) are widely used. It also will be the chemical composition and distribution of carbide particles therein. Two types of HSS are available in the market: HSS from Germany (Bohler) and HSS from China. This research employed the pure experimental design. It consists of two stages. The first, aims to test/operate lathe machines to determine the lifetime and performance of tools based on specified wear criteria. The second, characterization of microstructure using SEM-EDS was conducted. Firstly, grinding of toolss was done so that the toolss could be used for cutting metal in the turning process. Grinding processes of the two types of toolss were done at the same geometry, that is side rake angle (12°-18°), angle of keenness (60°-68°), and side relief angle (10°-12°). Likewise, machining parameters were set in the same machining conditions. Based on the results of the tests, it is found that to reach 0.2 mm wear point, toolss made of HSS from Germany needed 24 minutes, while toolss made of HSS from China needed 8 minutes. Next, microstructure tests using SEM/EDS were done. The results of the SEM tests indicate that the carbide particles of HSS from Germany were more evenly distributed than the carbide particles of HSS from China. Carbide compounds identified in HSS from China were Cr23C6 and Fe4Mo2C. Oxide impurity of Al2O3 was also found in the material. On the other hand, in HSS from Germany, no impurity and other carbide compounds were identified, except Cr23C6 and Fe4Mo2C, also Fe4W2C, and VC or V4C3.

  14. Modification of surface mechanical properties of high-chromium tool steel by carbon-implanted codeposited Fe-Ti films

    SciTech Connect

    Hirvonen, J.P.; Nastasi, M.; Jervis, T.R.; Zocco, T.G.

    1990-01-01

    An iron-titanium film 300 nm thick was deposited on a tool steel (1.55% C, 0.3% Si, 0.3% Mn, 12% Cr, 0.8% Mo, and 0.8% V) by coevaporation of Fe and Ti. Subsequently this surface film was implanted with carbon at energies of 55, 120, and 200 keV to a total fluence of 1.24 {times} 10{sup 18} C{sup +}/cm{sup 2}. This treatment produced a surface hardness of 15 GPa. The effect of this coating on unlubricated wear and friction was tested in air at a relative humidity of 10% in a pin-on-disc tester using a 440C pin as a counterface. The sliding mechanism of the untreated substrate was found to be based on the transfer of pin material and subsequent growth of uneven oxide hillocks on the wear track. Oxide scales were observed also on a wear scar of the pin, presumably as a result of back-deposition. In contrast, the sliding mechanism on the coated sample was drastically different. A more uniform transfer film originating in the coating was found on the pin, resulting in sliding between identical materials. No wearthrough of the coating occurred during the test of 5000 cycles at a Hertzian pressure of 835 MPa, and the surface of the wear track showed extreme smoothness to the very end of the test. The friction coefficient was decreased from 0.7 for the uncoated to 0.2 for the coated surface. The wear track on the coated surface was also found to be slightly oxidized, as determined by a nuclear reaction ({sup 16}O(d,p){sup 17}O). The reduction of friction was mainly attributed to the increased hardness of the counterfaces and an adequate but controlled oxidation. 15 refs., 7 figs., 2 tabs.

  15. Effect of Energy Input on the Characteristic of AISI H13 and D2 Tool Steels Deposited by a Directed Energy Deposition Process

    NASA Astrophysics Data System (ADS)

    Park, Jun Seok; Park, Joo Hyun; Lee, Min-Gyu; Sung, Ji Hyun; Cha, Kyoung Je; Kim, Da Hye

    2016-05-01

    Among the many additive manufacturing technologies, the directed energy deposition (DED) process has attracted significant attention because of the application of metal products. Metal deposited by the DED process has different properties than wrought metal because of the rapid solidification rate, the high thermal gradient between the deposited metal and substrate, etc. Additionally, many operating parameters, such as laser power, beam diameter, traverse speed, and powder mass flow rate, must be considered since the characteristics of the deposited metal are affected by the operating parameters. In the present study, the effect of energy input on the characteristics of H13 and D2 steels deposited by a direct metal tooling process based on the DED process was investigated. In particular, we report that the hardness of the deposited H13 and D2 steels decreased with increasing energy input, which we discuss by considering microstructural observations and thermodynamics.

  16. An investigation of force, surface roughness and chip in surface grinding of SKD 11 tool steel using minimum quantity lubrication-MQL technique

    NASA Astrophysics Data System (ADS)

    Soepangkat, Bobby O. P.; Agustin, H. C. Kis; Subiyanto, H.

    2017-06-01

    This research aimed to analyze the viability of the minimum quantity of lubricant (MQL) technique towards normal force, tangential force, surface roughness and chip formation in surface grinding of SKD 11 tool steel. The three surface grinding parameters were varied including the type of cooling method (MQL and dry), table speed, and depth of cut. Based on statistical analysis, depth of cut is the most influential factor which affects the four responses in both dry and MQL grinding. MQL could reduce normal force and tangential force considerably, but produce higher surface roughness. In MQL grinding, the chips removal took place mostly by shearing and fracturing.

  17. Effect of Ti Addition on Carbide Modification and the Microscopic Simulation of Impact Toughness in High-Carbon Cr-V Tool Steels

    NASA Astrophysics Data System (ADS)

    Cho, Ki Sub; Kim, Sang Il; Park, Sung Soo; Choi, Won Suk; Moon, Hee Kwon; Kwon, Hoon

    2016-01-01

    In D7 tool steel, which contains high levels of primary carbides, the influence of carbide modification by Ti addition was quantitatively analyzed. Considering the Griffith-Irwin energy criterion for crack growth, the impact energy was evaluated by substituting a microscopic factor of the normalized number density of carbides cracked during hardness indentation tests for the crack length. The impact energy was enhanced with Ti addition because Ti reduced and refined the primary M7C3 carbide phase of elongated morphology, reducing the probability of crack generation.

  18. Heat treatment of nitrided layer formed on X37CrMoV5-1 hot working tool steel

    NASA Astrophysics Data System (ADS)

    Ciski, A.; Wach, P.; Tacikowski, J.; Babul, T.; Šuchmann, P.

    2017-02-01

    The paper presents the technology consisting of combination of the nitriding process with subsequent austenitizing at temperature above eutectoid temperature of the Fe-C system and further rapid cooling. Such treatment will cause formation of the martensite in the area of the primarily nitrided layer and the additional precipitation hardening by tempering of heat treated steel. The article shows that the heat treatment process of nitrided layer formed on X37CrMoV5-1 steel leads to strengthening of surface layer, the substrate and the core of nitrided part. Heat treatment of nitrided steel with the tempering in inert (nitrogen) or active (ammonia) atmosphere can increase the thickness of the layer formed by short-term nitriding process. After the nitriding process of X37CrMoV5-1 steel the nitrided layer had a thickness of about 160 μm, while a subsurface layer of iron nitrides had a thickness of 7 μm. After subsequent quenching and tempering processes, the nitrided layer undergoes additional diffusion and its thickness is increased to about 220 μm (inert atmosphere) or 280 μm (active atmosphere). If the tempering process is carried out in an inert atmosphere, the primarily formed layer of iron nitrides disappears. Tempering in an active atmosphere leads to forming of white layer with a thickness of 7 μm. Basic properties of nitrided layers formed in such way, like the hardness and the wear resistance, are presented.

  19. FlaME: Flash Molecular Editor - a 2D structure input tool for the web.

    PubMed

    Dallakian, Pavel; Haider, Norbert

    2011-02-01

    So far, there have been no Flash-based web tools available for chemical structure input. The authors herein present a feasibility study, aiming at the development of a compact and easy-to-use 2D structure editor, using Adobe's Flash technology and its programming language, ActionScript. As a reference model application from the Java world, we selected the Java Molecular Editor (JME). In this feasibility study, we made an attempt to realize a subset of JME's functionality in the Flash Molecular Editor (FlaME) utility. These basic capabilities are: structure input, editing and depiction of single molecules, data import and export in molfile format. The result of molecular diagram sketching in FlaME is accessible in V2000 molfile format. By integrating the molecular editor into a web page, its communication with the HTML elements on this page is established using the two JavaScript functions, getMol() and setMol(). In addition, structures can be copied to the system clipboard. A first attempt was made to create a compact single-file application for 2D molecular structure input/editing on the web, based on Flash technology. With the application examples presented in this article, it could be demonstrated that the Flash methods are principally well-suited to provide the requisite communication between the Flash object (application) and the HTML elements on a web page, using JavaScript functions.

  20. FlaME: Flash Molecular Editor - a 2D structure input tool for the web

    PubMed Central

    2011-01-01

    Background So far, there have been no Flash-based web tools available for chemical structure input. The authors herein present a feasibility study, aiming at the development of a compact and easy-to-use 2D structure editor, using Adobe's Flash technology and its programming language, ActionScript. As a reference model application from the Java world, we selected the Java Molecular Editor (JME). In this feasibility study, we made an attempt to realize a subset of JME's functionality in the Flash Molecular Editor (FlaME) utility. These basic capabilities are: structure input, editing and depiction of single molecules, data import and export in molfile format. Implementation The result of molecular diagram sketching in FlaME is accessible in V2000 molfile format. By integrating the molecular editor into a web page, its communication with the HTML elements on this page is established using the two JavaScript functions, getMol() and setMol(). In addition, structures can be copied to the system clipboard. Conclusion A first attempt was made to create a compact single-file application for 2D molecular structure input/editing on the web, based on Flash technology. With the application examples presented in this article, it could be demonstrated that the Flash methods are principally well-suited to provide the requisite communication between the Flash object (application) and the HTML elements on a web page, using JavaScript functions. PMID:21284863

  1. High Power Picosecond Laser Surface Micro-texturing of H13 Tool Steel and Pattern Replication onto ABS Plastics via Injection Moulding

    NASA Astrophysics Data System (ADS)

    Otanocha, Omonigho B.; Li, Lin; Zhong, Shan; Liu, Zhu

    2016-03-01

    H13 tool steels are often used as dies and moulds for injection moulding of plastic components. Certain injection moulded components require micro-patterns on their surfaces in order to modify the physical properties of the components or for better mould release to reduce mould contamination. With these applications it is necessary to study micro-patterning to moulds and to ensure effective pattern transfer and replication onto the plastic component during moulding. In this paper, we report an investigation into high average powered (100 W) picosecond laser interactions with H13 tool steel during surface micro-patterning (texturing) and the subsequent pattern replication on ABS plastic material through injection moulding. Design of experiments and statistical modelling were used to understand the influences of laser pulse repetition rate, laser fluence, scanning velocity, and number of scans on the depth of cut, kerf width and heat affected zones (HAZ) size. The characteristics of the surface patterns are analysed. The process parameter interactions and significance of process parameters on the processing quality and efficiency are characterised. An optimum operating window is recommended. The transferred geometry is compared with the patterns generated on the dies. A discussion is made to explain the characteristics of laser texturing and pattern replication on plastics.

  2. Evaluation of a 2-Channel NIRS-Based Optical Brain Switch for Motor Disabilities' Communication Tools

    NASA Astrophysics Data System (ADS)

    Sagara, Kazuhiko; Kido, Kunihiko

    We have developed a portable NIRS-based optical BCI system that features a non-invasive, facile probe attachment and does not require muscle movement to control the target devices. The system consists of a 2-channel probe, a signal-processing unit, and an infrared-emission device, which measures the blood volume change in the participant's prefrontal cortex in a real time. We use the threshold logic as a switching technology, which transmits a control signal to a target device when the electrical waveforms exceed the pre-defined threshold. Eight healthy volunteers participated in the experiments and they could change the television channel or control the movement of a toy robot with average switching times of 11.5±5.3s and the hit rate was 83.3%. These trials suggest that this system provides a novel communication aid for people with motor disabilities.

  3. Influence of water-miscible cutting fluid on tool wear behavior of various coated high-speed steel tools in hobbing

    NASA Astrophysics Data System (ADS)

    Sato, Yuta; Matsuoka, Hironori; Kubo, Akio; Ono, Hajime; Ryu, Takahiro; Qiu, Hua; Nakae, Takashi; Shuto, Shuichi; Watanabe, Suguru; Anan, Ruito

    2017-04-01

    This paper deals with the influence of water-miscible cutting fluid on tool life (flank wear) compared with that with dry cutting and water-insoluble cutting oil in hobbing. Experiments were conducted by simulating hobbing by fly tool cutting on a milling machine. The following results were clarified. (1) The water-miscible cutting fluid used in the test prolongs the tool life for TiN-, TiAlN-, TiSiN- and AlCrSiN-coated tools in comparison with that obtained by dry cutting and water-insoluble cutting oil. (2) It was presumed that the tool wear decreases and the tool life is improved by the lubrication effect of the synthetic lubrication additive, mineral oil and sulfuric EP additive contained in the water-miscible cutting fluid, and also by the cooling effect.

  4. Relative Dimensional Change Evaluation of Vacuum Heat-Treated JIS SKD61 Hot-Work Tool Steels

    NASA Astrophysics Data System (ADS)

    Yeh, Shu-Hung; Chiu, Liu-Ho; Pan, Yeong-Tsuen; Lin, Shou-Chi

    2014-06-01

    JIS SKD61 hot-work steel is usually used as precision mold material for die casting; hence, it demands a higher level of dimensional stability during the hardening process, especially for fairly large sections. This study investigates the microstructural evolution and measures the relative dimensional changes in various tempering states. The results show that the retained austenitic contents of all quenched and tempered SKD61 steel specimens were less than 2%. When the tempering temperature reached 500 °C, the retained austenitic content decreased from 1.35 to 0.45%. TEM investigations revealed that a large number of secondary carbides, molybdenum-rich M2C and vanadium-rich MC carbides, precipitated near the dislocations when the tempering temperature reached 525 °C. A secondary hardening phenomenon and evident expansion phenomenon occurred as the tempering temperature exceeded 500 °C. These phenomena were mainly contributed by the precipitation of secondary carbides in hot-work steels. The reason is that only 0.9% of the retained austenite transformed into martensite as the tempering temperature reached 500 °C, allowing the hardness and dimensional change to be neglected.

  5. A 2 MV Van de Graaff accelerator as a tool for planetary and impact physics research

    SciTech Connect

    Mocker, Anna; Bugiel, Sebastian; Srama, Ralf; Auer, Siegfried; Baust, Guenter; Matt, Guenter; Otto, Katharina; Colette, Andrew; Drake, Keith; Kempf, Sascha; Munsat, Tobin; Shu, Anthony; Sternovsky, Zoltan; Fiege, Katherina; Postberg, Frank; Gruen, Eberhard; Heckmann, Frieder; Helfert, Stefan; Hillier, Jonathan; Mellert, Tobias; and others

    2011-09-15

    Investigating the dynamical and physical properties of cosmic dust can reveal a great deal of information about both the dust and its many sources. Over recent years, several spacecraft (e.g., Cassini, Stardust, Galileo, and Ulysses) have successfully characterised interstellar, interplanetary, and circumplanetary dust using a variety of techniques, including in situ analyses and sample return. Charge, mass, and velocity measurements of the dust are performed either directly (induced charge signals) or indirectly (mass and velocity from impact ionisation signals or crater morphology) and constrain the dynamical parameters of the dust grains. Dust compositional information may be obtained via either time-of-flight mass spectrometry of the impact plasma or direct sample return. The accurate and reliable interpretation of collected spacecraft data requires a comprehensive programme of terrestrial instrument calibration. This process involves accelerating suitable solar system analogue dust particles to hypervelocity speeds in the laboratory, an activity performed at the Max Planck Institut fuer Kernphysik in Heidelberg, Germany. Here, a 2 MV Van de Graaff accelerator electrostatically accelerates charged micron and submicron-sized dust particles to speeds up to 80 km s{sup -1}. Recent advances in dust production and processing have allowed solar system analogue dust particles (silicates and other minerals) to be coated with a thin conductive shell, enabling them to be charged and accelerated. Refinements and upgrades to the beam line instrumentation and electronics now allow for the reliable selection of particles at velocities of 1-80 km s{sup -1} and with diameters of between 0.05 {mu}m and 5 {mu}m. This ability to select particles for subsequent impact studies based on their charges, masses, or velocities is provided by a particle selection unit (PSU). The PSU contains a field programmable gate array, capable of monitoring in real time the particles' speeds and

  6. A 2 MV Van de Graaff accelerator as a tool for planetary and impact physics research.

    PubMed

    Mocker, Anna; Bugiel, Sebastian; Auer, Siegfried; Baust, Günter; Colette, Andrew; Drake, Keith; Fiege, Katherina; Grün, Eberhard; Heckmann, Frieder; Helfert, Stefan; Hillier, Jonathan; Kempf, Sascha; Matt, Günter; Mellert, Tobias; Munsat, Tobin; Otto, Katharina; Postberg, Frank; Röser, Hans-Peter; Shu, Anthony; Sternovsky, Zoltán; Srama, Ralf

    2011-09-01

    Investigating the dynamical and physical properties of cosmic dust can reveal a great deal of information about both the dust and its many sources. Over recent years, several spacecraft (e.g., Cassini, Stardust, Galileo, and Ulysses) have successfully characterised interstellar, interplanetary, and circumplanetary dust using a variety of techniques, including in situ analyses and sample return. Charge, mass, and velocity measurements of the dust are performed either directly (induced charge signals) or indirectly (mass and velocity from impact ionisation signals or crater morphology) and constrain the dynamical parameters of the dust grains. Dust compositional information may be obtained via either time-of-flight mass spectrometry of the impact plasma or direct sample return. The accurate and reliable interpretation of collected spacecraft data requires a comprehensive programme of terrestrial instrument calibration. This process involves accelerating suitable solar system analogue dust particles to hypervelocity speeds in the laboratory, an activity performed at the Max Planck Institut für Kernphysik in Heidelberg, Germany. Here, a 2 MV Van de Graaff accelerator electrostatically accelerates charged micron and submicron-sized dust particles to speeds up to 80 km s(-1). Recent advances in dust production and processing have allowed solar system analogue dust particles (silicates and other minerals) to be coated with a thin conductive shell, enabling them to be charged and accelerated. Refinements and upgrades to the beam line instrumentation and electronics now allow for the reliable selection of particles at velocities of 1-80 km s(-1) and with diameters of between 0.05 μm and 5 μm. This ability to select particles for subsequent impact studies based on their charges, masses, or velocities is provided by a particle selection unit (PSU). The PSU contains a field programmable gate array, capable of monitoring in real time the particles' speeds and charges, and

  7. Development of flank wear model of cutting tool by using adaptive feedback linear control system on machining AISI D2 steel and AISI 4340 steel

    NASA Astrophysics Data System (ADS)

    Orra, Kashfull; Choudhury, Sounak K.

    2016-12-01

    The purpose of this paper is to build an adaptive feedback linear control system to check the variation of cutting force signal to improve the tool life. The paper discusses the use of transfer function approach in improving the mathematical modelling and adaptively controlling the process dynamics of the turning operation. The experimental results shows to be in agreement with the simulation model and error obtained is less than 3%. The state space approach model used in this paper successfully check the adequacy of the control system through controllability and observability test matrix and can be transferred from one state to another by appropriate input control in a finite time. The proposed system can be implemented to other machining process under varying range of cutting conditions to improve the efficiency and observability of the system.

  8. Development of a carburizing and quenching simulation tool: A material model for low carbon steels undergoing phase transformations

    SciTech Connect

    Bammann, D.; Prantil, V.; Kumar, A.

    1996-06-24

    An internal state variable formulation for phase transforming alloy steels is presented. We have illustrated how local transformation plasticity can be accommodated by an appropriate choice for the corresponding internal stress field acting between the phases. The state variable framework compares well with a numerical micromechanical calculation providing a discrete dependence of microscopic plasticity on volume fraction and the stress dependence attributable to a softer parent phase. The multiphase model is used to simulate the stress state of a quenched bar and show qualitative trends in the response when the transformation phenomenon is incorporated on the length scale of a global boundary value problem.

  9. Subsurface Crack Initiation and Propagation Mechanism under the Super-Long Fatigue Regime for High Speed Tool Steel (JIS SKH51) by Fracture Surface Topographic Analysis

    NASA Astrophysics Data System (ADS)

    Shiozawa, Kazuaki; Morii, Yuuichi; Nishino, Seiichi

    In order to study the subsurface crack initiation and propagation mechanism of high strength steel under a very high cycle fatigue regime, computational simulation with fracture surface topographic analysis (FRASTA) was carried out for subsurface fatigue crack initiated specimens of high speed tool steel (JIS SKH51) obtained from the rotating bending fatigue test in air. A remarkable area formed around the nonmetallic inclusion inside the fish-eye region on the fracture surface, which is a feature on the fracture surface in super long fatigue. This so-called GBF (granular-bright-facet) was observed in detail by a scanning probe microscope and a three-dimensional SEM. The GBF area, in which a rich carbide distribution was detected by EPMA, revealed a very rough and granular morphology in comparison with the area inside the fish-eye. It was clearly simulated by FRASTA that multiple microcracks were initiated and dispersed by the decohesion of a spherical carbide from the matrix around a nonmetallic inclusion, and converged into the GBF area during the fatigue process. After the formation of the GBF area, interior cracks grew radially and a fish-eye pattern formed on the fracture surface.

  10. Magnetic Hysteresis Loop as a Tool for the Evaluation of Microstructure and Mechanical Properties of DP Steels

    NASA Astrophysics Data System (ADS)

    Mohapatra, J. N.; Kumar, Satendra; Akela, Arbind Kumar; Prakash Rao, S.; Kaza, Marutiram

    2016-06-01

    DP steel of 1.3-mm thickness full hard sheet was heat treated at different temperatures in the range of 700-850 °C with 25 °C step for 15 min soaking followed by water quenching. The variation of the soaking temperatures leads to variation of volume fraction of martensite which was measured by image analysis software in optical microscopy. Mechanical properties of the samples were evaluated using micro Vicker's hardness test and tensile test machine. Magnetic properties of the samples were measured by MagStar to correlate with the microstructure and mechanical properties of the samples. It was observed that the coercivity of the samples increased linearly with the increase in volume fraction of martensite and mechanical properties. Hence monitoring coercivity would help non-destructive evaluation of mechanical properties of the DP steels. Additionally, it would also helpful for the non-destructive evaluation of variation in heat treatment conditions since coercivity also found to increase linearly with the increase in soaking temperature.

  11. Comparison of surface roughness and chip characteristics obtained under different modes of lubrication during hard turning of AISI H13 tool work steel.

    NASA Astrophysics Data System (ADS)

    Raj, Anil; Wins, K. Leo Dev; Varadarajan, A. S.

    2016-09-01

    Surface roughness is one of the important parameters, which not only affects the service life of a component but also serves as a good index of machinability. Near Dry Machining, methods (NDM) are considered as sustainable alternative for workshops trying to bring down their dependence on cutting fluids and the hazards associated with their indiscriminate usage. The present work presents a comparison of the surface roughness and chip characteristics during hard turning of AISI H13 tool work steel using hard metal inserts under two popular NDM techniques namely the minimal fluid application and the Minimum Quantity Lubrication technique(MQL) using an experiment designed based on Taguchi's techniques. The statistical method of analysis of variance (ANOVA) was used to determine the relative significance of input parameters consisting of cutting speed, feed and depth of cut on the attainable surface finish and the chip characteristics. It was observed that the performance during minimal fluid application was better than that during MQL application.

  12. EBSD as a tool to identify and quantify bainite and ferrite in low-alloyed Al-TRIP steels.

    PubMed

    Zaefferer, S; Romano, P; Friedel, F

    2008-06-01

    Bainite is thought to play an important role for the chemical and mechanical stabilization of metastable austenite in low-alloyed TRIP steels. Therefore, in order to understand and improve the material properties, it is important to locate and quantify the bainitic phase. To this aim, electron backscatter diffraction-based orientation microscopy has been employed. The main difficulty herewith is to distinguish bainitic ferrite from ferrite because both have bcc crystal structure. The most important difference between them is the occurrence of transformation induced geometrically necessary dislocations in the bainitic phase. To determine the areas with larger geometrically necessary dislocation density, the following orientation microscopy maps were explored: pattern quality maps, grain reference orientation deviation maps and kernel average misorientation maps. We show that only the latter allow a reliable separation of the bainitic and ferritic phase. The kernel average misorientation threshold value that separates both constituents is determined by an algorithm that searches for the smoothness of the boundaries between them.

  13. Simulation of macrosegregation in a 2.45-ton steel ingot using a three-phase mixed columnar-equiaxed model☆

    PubMed Central

    Li, Jun; Wu, Menghuai; Ludwig, Andreas; Kharicha, Abdellah

    2014-01-01

    A three-phase mixed columnar-equiaxed solidification model is used to calculate the macrosegregation in a 2.45 ton steel ingot. The main features of mixed columnar-equiaxed solidification in such an ingot can be quantitatively modelled: growth of columnar dendrite trunks; nucleation, growth and sedimentation of equiaxed crystals; thermosolutal convection of the melt; solute transport by both convection and crystal sedimentation; and the columnar-to-equiaxed transition (CET). The predicted as-cast macrostructure and the segregation pattern are in qualitative agreement with the reported experimental results. Parameter study on the numerical grid size and the nucleation of the equiaxed crystals are performed, and some segregation mechanisms are numerically analyzed. Discontinued positive–negative segregation just below the hot top is predicted because of the formation of a local mini-ingot and the subsequent sedimentation of equiaxed grains within the mini-ingot. Quasi A-segregates in the middle radius region between the casting outer surface and the centreline are also found. The quasi A-segregates originate from the flow instability, but both the appearance of equiaxed crystals and their interaction with the growing columnar dendrite tips significantly strengthen the segregates. The appearance of equiaxed phase is not a necessary condition for the formation of quasi A-segregates. The quantitative discrepancy between the predicted and experimental results is also discussed. PMID:24795485

  14. Austenite Grain Growth in a 2.25Cr-1Mo Vanadium-Free Steel Accounting for Zener Pinning and Solute Drag: Experimental Study and Modeling

    NASA Astrophysics Data System (ADS)

    Dépinoy, S.; Marini, B.; Toffolon-Masclet, C.; Roch, F.; Gourgues-Lorenzon, A.-F.

    2017-02-01

    Austenite grain size has been experimentally determined for various austenitization temperatures and times in a 2.25Cr-1Mo vanadium-free steel. Three grain growth regimes were highlighted: limited growth occurs at lower temperatures [1193 K (920 °C) and 1243 K (970 °C)]; parabolic growth prevails at higher temperatures [1343 K (1070 °C) and 1393 K (1120 °C)]. At the intermediate temperature of 1293 K (1020 °C), slowed down growth was observed. Classical grain growth equations were applied to the experimental results, accounting for Zener pinning and solute drag as possible causes for temperature-dependent limited growth. It was shown that Zener pinning due to AlN particles could not be responsible for limited growth, although it has some effect at lower temperatures. Instead, limited and slow growths are very likely to be the result of segregation of molybdenum atoms at austenite grain boundaries. The temperature-dependence of this phenomenon may be linked to the co-segregation of molybdenum and carbon atoms.

  15. Austenite Grain Growth in a 2.25Cr-1Mo Vanadium-Free Steel Accounting for Zener Pinning and Solute Drag: Experimental Study and Modeling

    NASA Astrophysics Data System (ADS)

    Dépinoy, S.; Marini, B.; Toffolon-Masclet, C.; Roch, F.; Gourgues-Lorenzon, A.-F.

    2017-05-01

    Austenite grain size has been experimentally determined for various austenitization temperatures and times in a 2.25Cr-1Mo vanadium-free steel. Three grain growth regimes were highlighted: limited growth occurs at lower temperatures [1193 K (920 °C) and 1243 K (970 °C)]; parabolic growth prevails at higher temperatures [1343 K (1070 °C) and 1393 K (1120 °C)]. At the intermediate temperature of 1293 K (1020 °C), slowed down growth was observed. Classical grain growth equations were applied to the experimental results, accounting for Zener pinning and solute drag as possible causes for temperature-dependent limited growth. It was shown that Zener pinning due to AlN particles could not be responsible for limited growth, although it has some effect at lower temperatures. Instead, limited and slow growths are very likely to be the result of segregation of molybdenum atoms at austenite grain boundaries. The temperature-dependence of this phenomenon may be linked to the co-segregation of molybdenum and carbon atoms.

  16. Surface Roughness and Tool Wear on Cryogenic Treated CBN Insert on Titanium and Inconel 718 Alloy Steel

    NASA Astrophysics Data System (ADS)

    Thamizhmanii, S.; Mohideen, R.; Zaidi, A. M. A.; Hasan, S.

    2015-12-01

    Machining of materials by super hard tools like cubic boron nitride (cbn) and poly cubic boron nitride (pcbn) is to reduce tool wear to obtain dimensional accuracy, smooth surface and more number of parts per cutting edge. wear of tools is inevitable due to rubbing action between work material and tool edge. however, the tool wear can be minimized by using super hard tools by enhancing the strength of the cutting inserts. one such process is cryogenic process. this process is used in all materials and cutting inserts which requires wear resistance. the cryogenic process is executed under subzero temperature -186° celsius for longer period of time in a closed chamber which contains liquid nitrogen. in this research, cbn inserts with cryogenically treated was used to turn difficult to cut metals like titanium, inconel 718 etc. the turning parameters used is different cutting speeds, feed rates and depth of cut. in this research, titanium and inconel 718 material were used. the results obtained are surface roughness, flank wear and crater wear. the surface roughness obtained on titanium was lower at high cutting speed compared with inconel 718. the flank wear was low while turning titanium than inconel 718. crater wear is less on inconel 718 than titanium alloy. all the two materials produced saw tooth chips.

  17. Simulation of Drawing of Small Stainless Steel Platinum Medical Tubes—Influence of the Tool Parameters on the Forming Limit

    NASA Astrophysics Data System (ADS)

    Linardon, Camille; Affagard, Jean-Sébastien; Chagnon, Grégory; Favier, Denis; Gruez, Benoit

    2011-05-01

    Tube cold drawing processes are used to reduce tube diameters and thickness, while pulling them through a conical converging die with or without inner plug. An accurate modelling of the material deformation and friction behaviour is required in order to well describe these processes. The study concerns a stainless steel platinum alloy. The material behaviour is characterised through tensile tests at strain rates as close as possible to the high strain rates reached during the drawing process. The results are fitted with an isotropic temperature-independent Johnson Cook constitutive equation. The modelling of floating plug drawing is performed on a ABAQUS/Explicit model. Friction coefficient is difficult to estimate with mechanical experimental tests, thus an inverse analysis is carried out to fit this parameter thanks to finite element simulation and experimental drawing tests. Drawing force measurements are recorded during the forming process. The Cockroft-Latham criterion is applied to understand the different process parameters influence on tube drawing and its accuracy for drawing process is evaluated.

  18. Simulation of Drawing of Small Stainless Steel Platinum Medical Tubes--Influence of the Tool Parameters on the Forming Limit

    SciTech Connect

    Linardon, Camille; Affagard, Jean-Sebastien; Chagnon, Gregory; Favier, Denis; Gruez, Benoit

    2011-05-04

    Tube cold drawing processes are used to reduce tube diameters and thickness, while pulling them through a conical converging die with or without inner plug. An accurate modelling of the material deformation and friction behaviour is required in order to well describe these processes.The study concerns a stainless steel platinum alloy. The material behaviour is characterised through tensile tests at strain rates as close as possible to the high strain rates reached during the drawing process. The results are fitted with an isotropic temperature-independent Johnson Cook constitutive equation. The modelling of floating plug drawing is performed on a ABAQUS/Explicit model. Friction coefficient is difficult to estimate with mechanical experimental tests, thus an inverse analysis is carried out to fit this parameter thanks to finite element simulation and experimental drawing tests. Drawing force measurements are recorded during the forming process. The Cockroft-Latham criterion is applied to understand the different process parameters influence on tube drawing and its accuracy for drawing process is evaluated.

  19. Mechanism of generation of large (Ti,Nb,V)(C,N)-type precipitates in H13 + Nb tool steel

    NASA Astrophysics Data System (ADS)

    Xie, You; Cheng, Guo-guang; Chen, Lie; Zhang, Yan-dong; Yan, Qing-zhong

    2016-11-01

    The characteristics and generation mechanism of (Ti,Nb,V)(C,N) precipitates larger than 2 μm in Nb-containing H13 bar steel were studied. The results show that two types of (Ti,Nb,V)(C,N) phases exist—a Ti-V-rich one and an Nb-rich one—in the form of single or complex precipitates. The sizes of the single Ti-V-rich (Ti,Nb,V)(C,N) precipitates are mostly within 5 to 10 μm, whereas the sizes of the single Nb-rich precipitates are mostly 2-5 μm. The complex precipitates are larger and contain an inner Ti-V-rich layer and an outer Nb-rich layer. The compositional distribution of (Ti,Nb,V)(C,N) is concentrated. The average composition of the single Ti-V-rich phase is (Ti0.511V0.356Nb0.133)(C x N y ), whereas that for the single Nb-rich phase is (Ti0.061V0.263Nb0.676)(C x N y ). The calculation results based on the Scheil-Gulliver model in the Thermo-Calc software combining with the thermal stability experiments show that the large phases precipitate during the solidification process. With the development of solidification, the Ti-V-rich phase precipitates first and becomes homogeneous during the subsequent temperature reduction and heat treatment processes. The Nb-rich phase appears later.

  20. Cryogenic treatment of steels. (Latest citations from Metadex). Published Search

    SciTech Connect

    1998-03-01

    The bibliography contains citations concerning the use of cryogenic temperatures to improve the properties of steels. Stainless steels, tool steels, electrical steels, and metal matrix composites are discussed. Citations cover fatigue life, wear resistance, tool life, and increased high temperature ductility. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  1. Staking Tool for Hard Metals

    NASA Technical Reports Server (NTRS)

    Stein, J. A.

    1982-01-01

    Simple tool stakes hard-steel parts--that is, forces one part into recess on another, deforming receiving part so that it restrains inserted one. Tool allows small machine shops to stake hard steel without massive presses. Can be used, for example, to insert ball and spring into hard steel snap-tool body such as that used to turn socket wrenches. Use is not limited to hard steel; can be used as well to assemble parts made of softer materials.

  2. Optimization of process parameters on EN24 Tool steel using Taguchi technique in Electro-Discharge Machining (EDM)

    NASA Astrophysics Data System (ADS)

    Jeykrishnan, J.; Vijaya Ramnath, B.; Akilesh, S.; Pradeep Kumar, R. P.

    2016-09-01

    In the field of manufacturing sectors, electric discharge machining (EDM) is widely used because of its unique machining characteristics and high meticulousness which can't be done by other traditional machines. The purpose of this paper is to analyse the optimum machining parameter, to curtail the machining time with respect to high material removal rate (MRR) and low tool wear rate (TWR) by varying the parameters like current, pulse on time (Ton) and pulse off time (Toff). By conducting several dry runs using Taguchi technique of L9 orthogonal array (OA), optimized parameters were found using analysis of variance (ANOVA) and the error percentage can be validated and parameter contribution for MRR and TWR were found.

  3. Performance Steel Castings

    DTIC Science & Technology

    2012-09-30

    alloys , foundry, muzzle brake, supply center, tooling, sources Notice Distribution Statement A Format Information Report created in Microsoft Word...Development of Sand Properties 103 Advanced Modeling Dataset.. 105 High Strength Low Alloy (HSLA) Steels 107 Steel Casting and Engineering Support...University, University of Northern Iowa, Non- Ferrous Founders’ Society, QuesTek, buyCASTINGS.com, Spokane Industries, Nova Precision Casting, Waukesha

  4. Effect of inclusion size on the high cycle fatigue strength and failure mode of a high V alloyed powder metallurgy tool steel

    NASA Astrophysics Data System (ADS)

    Yao, Jun; Qu, Xuan-hui; He, Xin-bo; Zhang, Lin

    2012-07-01

    The fatigue strength of a high V alloyed powder metallurgy tool steel with two different inclusion size levels, tempered at different temperatures, was investigated by a series of high cycle fatigue tests. It was shown that brittle inclusions with large sizes above 30 μm prompted the occurrence of subsurface crack initiation and the reduction in fatigue strength. The fracture toughness and the stress amplitude both exerted a significant influence on the fish-eye size. A larger fish-eye area would form in the sample with a higher fracture toughness subjected to a lower stress amplitude. The stress intensity factor of the inclusion was found to lie above a typical value of the threshold stress intensity factor of 4 MPa·m1/2. The fracture toughness of the sample with a hardness above HRC 56 could be estimated by the mean value of the stress intensity factor of the fish-eye. According to fractographic evaluation, the critical inclusion size can be calculated by linear fracture mechanics.

  5. Atom probe study of the carbon distribution in a hardened martensitic hot-work tool steel X38CrMoV5-1.

    PubMed

    Lerchbacher, Christoph; Zinner, Silvia; Leitner, Harald

    2012-07-01

    The microstructure of the hardened common hot-work tool steel X38CrMoV5-1 has been characterized by atom probe tomography with the focus on the carbon distribution. Samples quenched with technically relevant cooling parameters λ from 0.1 (30 K/s) to 12 (0.25 K/s) have been investigated. The parameter λ is an industrially commonly used exponential cooling parameter, representing the cooling time from 800 to 500 °C in seconds divided with hundred. In all samples pronounced carbon segregation to dislocations and cluster formation could be observed after quenching. Carbon enriched interlath films with peak carbon levels of 6-10 at.%, which have been identified to be retained austenite by TEM, show a thickness increase with increasing λ. Therefore, the fraction of total carbon staying in the austenite grows. This carbon is not available for the tempering induced precipitation of secondary carbides in the bulk. Through all samples no segregation of any substitutional elements takes place. Charpy impact testing and fracture surface analysis of the hardened samples reveal the cooling rate induced microstructural distinctions.

  6. Influence of different temperatures on the thermal fatigue behavior and thermal stability of hot-work tool steel processed by a biomimetic couple laser technique

    NASA Astrophysics Data System (ADS)

    Meng, Chao; Zhou, Hong; Zhou, Ying; Gao, Ming; Tong, Xin; Cong, Dalong; Wang, Chuanwei; Chang, Fang; Ren, Luquan

    2014-04-01

    Three kinds of biomimetic non-smooth shapes (spot-shape, striation-shape and reticulation-shape) were fabricated on the surface of H13 hot-work tool steel by laser. We investigated the thermal fatigue behavior of biomimetic non-smooth samples with three kinds of shapes at different thermal cycle temperature. Moreover, the evolution of microstructure, as well as the variations of hardness of laser affected area and matrix were studied and compared. The results showed that biomimetic non-smooth samples had better thermal fatigue behavior compared to the untreated samples at different thermal cycle temperatures. For a given maximal temperature, the biomimetic non-smooth sample with reticulation-shape had the optimum thermal fatigue behavior, than with striation-shape which was better than that with the spot-shape. The microstructure observations indicated that at different thermal cycle temperatures the coarsening degrees of microstructures of laser affected area were different and the microstructures of laser affected area were still finer than that of the untreated samples. Although the resistance to thermal cycling softening of laser affected area was lower than that of the untreated sample, laser affected area had higher microhardness than the untreated sample at different thermal cycle temperature.

  7. Optimization of multi response in end milling process of ASSAB XW-42 tool steel with liquid nitrogen cooling using Taguchi-grey relational analysis

    NASA Astrophysics Data System (ADS)

    Norcahyo, Rachmadi; Soepangkat, Bobby O. P.

    2017-06-01

    A research was conducted for the optimization of the end milling process of ASSAB XW-42 tool steel with multiple performance characteristics based on the orthogonal array with Taguchi-grey relational analysis method. Liquid nitrogen was applied as a coolant. The experimental studies were conducted under varying the liquid nitrogen cooling flow rates (FL), and the end milling process variables, i.e., cutting speed (Vc), feeding speed (Vf), and axial depth of cut (Aa). The optimized multiple performance characteristics were surface roughness (SR), flank wear (VB), and material removal rate (MRR). An orthogonal array, signal-to-noise (S/N) ratio, grey relational analysis, grey relational grade, and analysis of variance were employed to study the multiple performance characteristics. Experimental results showed that flow rate gave the highest contribution for reducing the total variation of the multiple responses, followed by cutting speed, feeding speed, and axial depth of cut. The minimum surface roughness, flank wear, and maximum material removal rate could be obtained by using the values of flow rate, cutting speed, feeding speed, and axial depth of cut of 0.5 l/minute, 109.9 m/minute, 440 mm/minute, and 0.9 mm, respectively.

  8. Influence of Tool Rotational Speed and Post-Weld Heat Treatments on Friction Stir Welded Reduced Activation Ferritic-Martensitic Steel

    NASA Astrophysics Data System (ADS)

    Manugula, Vijaya L.; Rajulapati, Koteswararao V.; Reddy, G. Madhusudhan; Mythili, R.; Bhanu Sankara Rao, K.

    2017-08-01

    The effects of tool rotational speed (200 and 700 rpm) on evolving microstructure during friction stir welding (FSW) of a reduced activation ferritic-martensitic steel (RAFMS) in the stir zone (SZ), thermo-mechanically affected zone (TMAZ), and heat-affected zone (HAZ) have been explored in detail. The influence of post-weld direct tempering (PWDT: 1033 K (760 °C)/ 90 minutes + air cooling) and post-weld normalizing and tempering (PWNT: 1253 K (980 °C)/30 minutes + air cooling + tempering 1033 K (760 °C)/90 minutes + air cooling) treatments on microstructure and mechanical properties has also been assessed. The base metal (BM) microstructure was tempered martensite comprising Cr-rich M23C6 on prior austenite grain and lath boundaries with intra-lath precipitation of V- and Ta-rich MC precipitates. The tool rotational speed exerted profound influence on evolving microstructure in SZ, TMAZ, and HAZ in the as-welded and post-weld heat-treated states. Very high proportion of prior austenitic grains and martensite lath boundaries in SZ and TMAZ in the as-welded state showed lack of strengthening precipitates, though very high hardness was recorded in SZ irrespective of the tool speed. Very fine-needle-like Fe3C precipitates were found at both the rotational speeds in SZ. The Fe3C was dissolved and fresh precipitation of strengthening precipitates occurred on both prior austenite grain and sub-grain boundaries in SZ during PWNT and PWDT. The post-weld direct tempering caused coarsening and coalescence of strengthening precipitates, in both matrix and grain boundary regions of TMAZ and HAZ, which led to inhomogeneous distribution of hardness across the weld joint. The PWNT heat treatment has shown fresh precipitation of M23C6 on lath and grain boundaries and very fine V-rich MC precipitates in the intragranular regions, which is very much similar to that prevailed in BM prior to FSW. Both the PWDT and PWNT treatments caused considerable reduction in the hardness of SZ

  9. Virtual Steel Connection Sculpture--Student Learning Assessment

    ERIC Educational Resources Information Center

    Chou, Karen C.; Moaveni, Saeed; Drane, Denise

    2016-01-01

    A Virtual Steel Connection Sculpture was developed through a grant from the National Science Foundation. The Virtual Sculpture is an interactive tool that shows students and anyone interested in connections how steel members are connected. This tool is created to complement students' steel design courses. The features of this educational tool,…

  10. Virtual Steel Connection Sculpture--Student Learning Assessment

    ERIC Educational Resources Information Center

    Chou, Karen C.; Moaveni, Saeed; Drane, Denise

    2016-01-01

    A Virtual Steel Connection Sculpture was developed through a grant from the National Science Foundation. The Virtual Sculpture is an interactive tool that shows students and anyone interested in connections how steel members are connected. This tool is created to complement students' steel design courses. The features of this educational tool,…

  11. Development of a 2nd Generation Decision Support Tool to Optimize Resource and Energy Recovery for Municipal Solid Waste

    EPA Science Inventory

    In 2012, EPA’s Office of Research and Development released the MSW decision support tool (MSW-DST) to help identify strategies for more sustainable MSW management. Depending upon local infrastructure, energy grid mix, population density, and waste composition and quantity, the m...

  12. Development of a 2nd Generation Decision Support Tool to Optimize Resource and Energy Recovery for Municipal Solid Waste

    EPA Science Inventory

    In 2012, EPA’s Office of Research and Development released the MSW decision support tool (MSW-DST) to help identify strategies for more sustainable MSW management. Depending upon local infrastructure, energy grid mix, population density, and waste composition and quantity, the m...

  13. Design and Implementation of the Control System for a 2 kHz Rotary Fast Tool Servo

    SciTech Connect

    Montesanti, R C; Trumper, D L

    2004-03-29

    This paper presents a summary of the performance of our 2 kHz rotary fast tool servo and an overview of its control systems. We also discuss the loop shaping techniques used to design the power amplifier current control loop and the implementation of that controller in an op-amp circuit. The design and development of the control system involved a long list of items including: current compensation; tool position compensation; notch filter design and phase stabilizing with an additional pole for a plant with an undamped resonance; adding viscous damping to the fast tool servo; voltage budget for driving real and reactive loads; dealing with unwanted oscillators; ground loops; digital-to-analog converter glitches; electrical noise from the spindle motor switching power supply; and filtering the spindle encoder signal to generate smooth tool tip trajectories. Eventually, all of these topics will be discussed in detail in a Ph.D. thesis that will include this work. For the purposes of this paper, rather than present a diluted discussion that attempts to touch on all of these topics, we will focus on the first item with sufficient detail for providing insight into the design process.

  14. Target hopping as a useful tool for the identification of novel EphA2 protein-protein antagonists.

    PubMed

    Tognolini, Massimiliano; Incerti, Matteo; Pala, Daniele; Russo, Simonetta; Castelli, Riccardo; Hassan-Mohamed, Iftiin; Giorgio, Carmine; Lodola, Alessio

    2014-01-01

    Lithocholic acid (LCA), a physiological ligand for the nuclear receptor FXR and the G-protein-coupled receptor TGR5, has been recently described as an antagonist of the EphA2 receptor, a key member of the ephrin signalling system involved in tumour growth. Given the ability of LCA to recognize FXR, TGR5, and EphA2 receptors, we hypothesized that the structural requirements for a small molecule to bind each of these receptors might be similar. We therefore selected a set of commercially available FXR or TGR5 ligands and tested them for their ability to inhibit EphA2 by targeting the EphA2-ephrin-A1 interface. Among the selected compounds, the stilbene carboxylic acid GW4064 was identified as an effective antagonist of EphA2, being able to block EphA2 activation in prostate carcinoma cells, in the micromolar range. This finding proposes the "target hopping" approach as a new effective strategy to discover new protein-protein interaction inhibitors.

  15. A 2D Fourier tool for the analysis of photo-elastic effect in large granular assemblies

    NASA Astrophysics Data System (ADS)

    Leśniewska, Danuta

    2017-06-01

    Fourier transforms are the basic tool in constructing different types of image filters, mainly those reducing optical noise. Some DIC or PIV software also uses frequency space to obtain displacement fields from a series of digital images of a deforming body. The paper presents series of 2D Fourier transforms of photo-elastic transmission images, representing large pseudo 2D granular assembly, deforming under varying boundary conditions. The images related to different scales were acquired using the same image resolution, but taken at different distance from the sample. Fourier transforms of images, representing different stages of deformation, reveal characteristic features at the three (`macro-`, `meso-` and `micro-`) scales, which can serve as a data to study internal order-disorder transition within granular materials.

  16. Aircraft Steels

    DTIC Science & Technology

    2009-02-19

    NAWCADPAX/TR-2009/ 12 AIRCRAFT STEELS by E. U. Lee R. Taylor C. Lei H. C. Sanders 19 February 2009...MARYLAND NAWCADPAX/TR-2009/ 12 19 February 2009 AIRCRAFT STEELS by E. U. Lee R. Taylor C. Lei H. C. Sanders...Prescribed by ANSI Std. Z39-18 NAWCADPAX/TR-2009/ 12 ii SUMMARY Five high strength and four stainless steels have been studied, identifying their

  17. Hypereutectoid high-speed steels

    SciTech Connect

    Kremnev, L.S.

    1986-01-01

    Half of the tungsten and molybdenum contained in R6M5 and R18 steels is concentrated in the undissolved eutectic carbides hindering austenitic grain gowth in hardening and providing the necessary strength and impact strength. This article describes the tungsten-free low-alloy high-speed steel 11M5F with a chemical composition of 1.03-1.10% C, 5.2-5.7% Mo, 3.8-4.2% Cr, 1.3-1.7% V, 0.3-0.6% Si, and 0.3% Ce. The properties of 11M5F and R6M5 steels are examined and compared. The results of production and laboratory tests of the cutting properties of tools of the steels developed showed their high effectiveness, especially of 11M5F steel with 1% A1. The life of tools of the tungsten-free steels is two or three times greater than the life of tools of R6M5 steel.

  18. Friction Stir Spot Welding (FSSW) of Advanced High Strength Steel (AHSS)

    SciTech Connect

    Santella, M. L.; Hovanski, Yuri; Pan, Tsung-Yu

    2012-04-16

    Friction stir spot welding (FSSW) is applied to join advanced high strength steels (AHSS): galvannealed dual phase 780 MPa steel (DP780GA), transformation induced plasticity 780 MPa steel (TRIP780), and hot-stamped boron steel (HSBS). A low-cost Si3N4 ceramic tool was developed and used for making welds in this study instead of polycrystalline cubic boron nitride (PCBN) material used in earlier studies. FSSW has the advantages of solid-state, low-temperature process, and the ability of joining dissimilar grade of steels and thicknesses. Two different tool shoulder geometries, concave with smooth surface and convex with spiral pattern, were used in the study. Welds were made by a 2-step displacement control process with weld time of 4, 6, and 10 seconds. Static tensile lap-shear strength achieved 16.4 kN for DP780GA-HSBS and 13.2kN for TRIP780-HSBS, above the spot weld strength requirements by AWS. Nugget pull-out was the failure mode of the joint. The joining mechanism was illustrated from the cross-section micrographs. Microhardness measurement showed hardening in the upper sheet steel (DP780GA or TRIP780) in the weld, but softening of HSBS in the heat-affect zone (HAZ). The study demonstrated the feasibility of making high-strength AHSS spot welds with low-cost tools.

  19. Friction Stir Spot Welding of DP780 and Hot-Stamp Boron Steels

    SciTech Connect

    Santella, Michael L.; Frederick, Alan; Hovanski, Yuri; Grant, Glenn J.

    2008-05-16

    Friction stir spot welds were made in two high-strength steels: DP780, and a hot-stamp-boron steel with tensile strength of 1500 MPa. The spot welds were made at either 800 or 1600 rpm using either of two polycrystalline boron nitride tools. One stir tool, BN77, had the relatively common pin-tool shape. The second tool, BN46, had a convex rather than a concave shoulder profile and a much wider and shorter pin. The tools were plunged to preprogrammed depths either at a continuous rate (1-step schedule) or in two segments consisting of a relatively high rate followed by a slower rate. In all cases, the welds were completed in 4s. The range of lap-shear values were compared to values required for resistance spot welds on the same steels. The minimum value of 10.3 kN was exceeded for friction stir spot welding of DP780 using a 2-step schedule and either the BN77- or the BN46-type stir tool. The respective minimum value of 12 kN was also exceeded for the HSB steel using the 2-step process and the BN46 stir tool.

  20. Friction Stir Spot Welding of DP780 and Hot-Stamp Boron Steels

    SciTech Connect

    Santella, Michael L; Frederick, David Alan; Hovanski, Yuri; Grant, Glenn J

    2008-01-01

    Friction stir spot welds were made in two high-strength steels: DP780, and a hot-stamp-boron steel with tensile strength of 1500 MPa. The spot welds were made at either 800 or 1600 rpm using either of two polycrystalline boron nitride tools. One stir tool, BN77, had the relatively common pin-tool shape. The second tool, BN46, had a convex rather than a concave shoulder profile and a much wider and shorter pin. The tools were plunged to preprogrammed depths either at a continuous rate (1-step schedule) or in two segments consisting of a relatively high rate followed by a slower rate. In all cases, the welds were completed in 4s. The range of lap-shear values were compared to values required for resistance spot welds on the same steels. The minimum value of 10.3 kN was exceeded for friction stir spot welding of DP780 using a 2-step schedule and either the BN77- or the BN46-type stir tool. The respective minimum value of 12 kN was also exceeded for the HSB steel using the 2-step process and the BN46 stir tool.

  1. Novel experimental methods for investigating high speed friction of titanium-aluminum-vanadium/tool steel interface and dynamic failure of extrinsically toughened DRA composites

    NASA Astrophysics Data System (ADS)

    Irfan, Mohammad Abdulaziz

    Dynamic deformation, flow, and failure are integral parts of all dynamic processes in materials. Invariably, dynamic failure also involves the relative sliding of one component of the material over the other. Advances in elucidation of these failure mechanisms under high loading rates has been of great interest to scientists working in this area. The need to develop new dynamic mechanical property tests for materials under well characterized and controllable loading conditions has always been a challenge to experimentalists. The current study focuses on the development of two experimental methods to study some aspects of dynamic material response. The first part focuses on the development of a single stage gas gun facility for investigating high-speed metal to metal interfacial friction with applications to high speed machining. During the course of this investigation a gas gun was designed and built capable of accelerating projectiles upto velocities of 1 km/s. Using this gas gun pressure-shear plate impact friction experiments were conducted to simulate conditions similar to high speed machining at the tool-workpiece interface. The impacting plates were fabricated from materials representing the tribo-pair of interest. Accurate measurements of the interfacial tractions, i.e. the normal pressure and the frictional stress at the tribo-pair interface, and the interfacial slip velocity could be made by employing laser interferometry. Normal pressures of the order of 1-2 MPa were generated and slipping velocities of the order of 50 m/s were obtained. In order to illustrate the structure of the constitutive law governing friction, the study included experimental investigation of frictional response to step changes in normal pressure and interfacial shear stress. The results of these experiments indicate that sliding resistance for Ti6Al4V/CH steel interface is much lower than measured under quasi-static sliding conditions. Also the temperature at the interface strongly

  2. EFFECT OF TOOL FEATURE ON THE JOINT STRENGTH OF DISSIMILAR FRICTION STIR LAP WELDS

    SciTech Connect

    Jana, Saumyadeep; Hovanski, Yuri; Grant, Glenn J.; Mattlin, Karl F.

    2011-04-25

    Several variations of friction stir tools were used to investigate the effects on the joint strengths of dissimilar friction stir lap welds. In the present lap weld configuration the top sheet was a 2.32 mm thick Mg (AZ 31) alloy. The bottom sheet consisted of two different steels, a (i) 0.8 mm thick electro-galvanized (EG) mild steel, or a (ii) 1.5 mm thick hot dip galvanized (HDG) high strength low alloy (HSLA) steel. Initially the tool shape was modified to accommodate the material, at which point the tool geometry was fixed. With a fixed tool geometry an additional feature was added to the pin bottom on one of the tools by incorporating a short hard insert, which would act as a stronger bottom sheet cutter. The effects of such modification on the unguided lap shear strength, and associated microstructural changes are discussed in this study.

  3. Fatigue handbook: Offshore steel structures

    SciTech Connect

    Almarnaess, A.

    1985-01-01

    The contents of this book are: Overview of Offshore Steel Structures; Loads on Ocean Structures; Fracture Mechanics As a Tool in Fatigue Analysis; Basic Fatigue Properties of Welded Joints; Significance of Defects; Improving the Fatigue Strength of Welded Joints; Effects of Marine Environment and Cathodic Protection on Fatigue of Structural Steels Fatigue of Tubular Joints; Unstable Fracture; Fatigue Life Calculations; and Fatigue in Building Codes Background and Applications.

  4. 49 CFR 178.504 - Standards for steel drums.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Standards for steel drums. 178.504 Section 178.504...-bulk Performance-Oriented Packaging Standards § 178.504 Standards for steel drums. (a) The following are identification codes for steel drums: (1) 1A1 for a non-removable head steel drum; and (2) 1A2...

  5. 49 CFR 178.504 - Standards for steel drums.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Standards for steel drums. 178.504 Section 178.504...-Oriented Packaging Standards § 178.504 Standards for steel drums. (a) The following are identification codes for steel drums: (1) 1A1 for a non-removable head steel drum; and (2) 1A2 for a removable...

  6. 49 CFR 178.504 - Standards for steel drums.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Standards for steel drums. 178.504 Section 178.504...-Oriented Packaging Standards § 178.504 Standards for steel drums. (a) The following are identification codes for steel drums: (1) 1A1 for a non-removable head steel drum; and (2) 1A2 for a removable...

  7. 49 CFR 178.504 - Standards for steel drums.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Standards for steel drums. 178.504 Section 178.504...-Oriented Packaging Standards § 178.504 Standards for steel drums. (a) The following are identification codes for steel drums: (1) 1A1 for a non-removable head steel drum; and (2) 1A2 for a removable...

  8. 49 CFR 178.504 - Standards for steel drums.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Standards for steel drums. 178.504 Section 178.504...-Oriented Packaging Standards § 178.504 Standards for steel drums. (a) The following are identification codes for steel drums: (1) 1A1 for a non-removable head steel drum; and (2) 1A2 for a removable...

  9. Stainless steel

    SciTech Connect

    Lula, R.A.

    1985-01-01

    This book discusses the stainless steels for high-strength, heat-resistant or corrosion-resistant applications. It is a treatment of the properties and selection of stainless steels. Up-to-date information covers physical, mechanical and chemical properties of all stainless grades, including the new ferritic and duplex grades. The book covers physical metallurgy as well as processing and service characteristics, including service in corrosive environments. It deals with wrought and cast stainless steels and reviews fabrication from cold-forming to powder metallurgy.

  10. Simultaneous Modification of Alumina and MgO·Al2O3 Inclusions by Calcium Treatment During Electroslag Remelting of Stainless Tool Steel

    NASA Astrophysics Data System (ADS)

    Shi, Cheng-Bin; Yu, Wen-Tao; Wang, Hao; Li, Jing; Jiang, Min

    2017-02-01

    Calcium modification of both alumina and MgO·Al2O3 inclusions during protective gas electroslag remelting (P-ESR) of 8Cr17MoV stainless steel and its effect on nitrides and primary carbides were studied by analyzing the transient evolution of oxide and sulfide inclusions in the P-ESR process. The oxide inclusions that were not removed during P-ESR without calcium treatment were found to retain their original state until in as-cast ingot. Calcium treatment modified all MgO·Al2O3 and alumina inclusions that had not been removed in the P-ESR process to liquid/partially liquid CaO-Al2O3-(MgO) with uniformly distributed elements, in addition to a small proportion of partially modified inclusions of a CaO-MgO-Al2O3 core surrounded by a liquid CaO-Al2O3. The modification of low-MgO-containing MgO·Al2O3 inclusions involves the preferential reduction of MgO from the MgO·Al2O3 inclusion by calcium and the reaction of calcium with Al2O3 in the inclusion. It is the incomplete/complete reduction of MgO from the spinel by calcium that contributes to the modification of spinels. Alumina inclusions were liquefied by direct reaction with calcium. Calcium treatment during P-ESR refining also provided an effective approach to prevent the formation of nitrides and primary carbides in stainless steel through modifying their preferred nucleation sites (alumina and MgO·Al2O3 inclusions) to calcium aluminates, which made no contribution to improving the steel cleanliness.

  11. Mössbauer spectroscopic investigation of retained-austenite content of high-carbon tool steel during isothermal tempering of as-quenched samples

    NASA Astrophysics Data System (ADS)

    Bała, Piotr; Krawczyk, Janusz; Hanc, Aneta

    2009-04-01

    This work presents the results of investigations using Mössbauer spectroscopy technique and their interpretation concerning retained austenite (RA) and its transformation during tempering in relation to previously conducted dilatometric, microscopic and mechanical investigations. This research was conducted on a new high-carbon alloy steel 120 MnCrMoV8-6-4-2, which was designed in 1998, in Phase Transformations Research Group at the AGH UST. The influence of the tempering time on the mechanical and chemical stability of retained austenite and on the products of its transformation, nucleation and solubility of ɛ carbides and cementite nucleation and growth, was determined.

  12. Tribological and mechanical properties of Ti/TiAlN/TiAlCN nanoscale multilayer PVD coatings deposited on AISI H11 hot work tool steel

    NASA Astrophysics Data System (ADS)

    AL-Bukhaiti, M. A.; Al-hatab, K. A.; Tillmann, W.; Hoffmann, F.; Sprute, T.

    2014-11-01

    A new [Ti/TiAlN/TiAlCN]5 multilayer coatings were deposited onto polished substrate AISI H11 (DIN 1.2343) steel by an industrial magnetron sputtering device. The tribological performance of the coated system was investigated by a ball-on-disk tribometer against 100Cr6 steel and Al2O3 balls. The friction coefficients and specific wear rates were measured at various normal loads (2, 5, 8, and 10 N) and sliding velocities (0.2, 0.4, and 0.8 m/s) in ambient air and dry conditions. The phase structure, composition, wear tracks morphologies, hardness, and film/substrate adhesion of the coatings were characterized by light-microscopy, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), 3D-surface analyzer, nanoindentation, and scratch tests. Results showed that the deposited coatings showed low wear rates in the scale of 10-15 m3/N m, low friction coefficients against 100Cr6 and Al2O3 balls in the range of 0.25-0.37, and good hardness in the range of 17-20 GPa. Results also revealed that the friction coefficients and disc wear rates decrease and increase, respectively with the increase in normal load and sliding velocity for both coating/Al2O3 and coating/100Cr6 sliding system. Compared with the uncoated-H11 substrate, the deposited coating exhibited superior tribological and mechanical properties. The dominant wear mechanism was abrasive wear for coating/Al2O3 pair, while for coating/100Cr6 pair, a combination of mild adhesive wear, severe adhesive wear, and abrasive wear (extensive plowing) were the dominant wear mechanisms at different applied normal loads.

  13. 76 FR 12322 - Certain Cut-to-Length Carbon-Quality Steel Plate From India, Indonesia, Italy, Japan, and the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-07

    ... ASTM A710 and A736 or their proprietary equivalents; (4) abrasion-resistant steels (i.e., USS AR 400... equivalents; (6) ball bearing steels; (7) tool steels; and (8) silicon manganese steel or silicon electric... International Trade Administration Certain Cut-to-Length Carbon-Quality Steel Plate From India, Indonesia,...

  14. Alkylation of histidine residues of Bothrops jararacussu venom proteins and isolated phospholipases A2: a biotechnological tool to improve the production of antibodies.

    PubMed

    Guimarães, C L S; Andrião-Escarso, S H; Moreira-Dill, L S; Carvalho, B M A; Marchi-Salvador, D P; Santos-Filho, N A; Fernandes, C A H; Fontes, M R M; Giglio, J R; Barraviera, B; Zuliani, J P; Fernandes, C F C; Calderón, L A; Stábeli, R G; Albericio, F; da Silva, S L; Soares, A M

    2014-01-01

    Crude venom of Bothrops jararacussu and isolated phospholipases A2 (PLA2) of this toxin (BthTX-I and BthTX-II) were chemically modified (alkylation) by p-bromophenacyl bromide (BPB) in order to study antibody production capacity in function of the structure-function relationship of these substances (crude venom and PLA2 native and alkylated). BthTX-II showed enzymatic activity, while BthTX-I did not. Alkylation reduced BthTX-II activity by 50% while this process abolished the catalytic and myotoxic activities of BthTX-I, while reducing its edema-inducing activity by about 50%. Antibody production against the native and alkylated forms of BthTX-I and -II and the cross-reactivity of antibodies to native and alkylated toxins did not show any apparent differences and these observations were reinforced by surface plasmon resonance (SPR) data. Histopathological analysis of mouse gastrocnemius muscle sections after injection of PBS, BthTX-I, BthTX-II, or both myotoxins previously incubated with neutralizing antibody showed inhibition of the toxin-induced myotoxicity. These results reveal that the chemical modification of the phospholipases A2 (PLA2) diminished their toxicity but did not alter their antigenicity. This observation indicates that the modified PLA2 may provide a biotechnological tool to attenuate the toxicity of the crude venom, by improving the production of antibodies and decreasing the local toxic effects of this poisonous substance in animals used to produce antivenom.

  15. Alkylation of Histidine Residues of Bothrops jararacussu Venom Proteins and Isolated Phospholipases A2: A Biotechnological Tool to Improve the Production of Antibodies

    PubMed Central

    Guimarães, C. L. S.; Andrião-Escarso, S. H.; Moreira-Dill, L. S.; Carvalho, B. M. A.; Marchi-Salvador, D. P.; Santos-Filho, N. A.; Fernandes, C. A. H.; Fontes, M. R. M.; Giglio, J. R.; Barraviera, B.; Zuliani, J. P.; Fernandes, C. F. C.; Calderón, L. A.; Stábeli, R. G.; Albericio, F.; da Silva, S. L.; Soares, A. M.

    2014-01-01

    Crude venom of Bothrops jararacussu and isolated phospholipases A2 (PLA2) of this toxin (BthTX-I and BthTX-II) were chemically modified (alkylation) by p-bromophenacyl bromide (BPB) in order to study antibody production capacity in function of the structure-function relationship of these substances (crude venom and PLA2 native and alkylated). BthTX-II showed enzymatic activity, while BthTX-I did not. Alkylation reduced BthTX-II activity by 50% while this process abolished the catalytic and myotoxic activities of BthTX-I, while reducing its edema-inducing activity by about 50%. Antibody production against the native and alkylated forms of BthTX-I and -II and the cross-reactivity of antibodies to native and alkylated toxins did not show any apparent differences and these observations were reinforced by surface plasmon resonance (SPR) data. Histopathological analysis of mouse gastrocnemius muscle sections after injection of PBS, BthTX-I, BthTX-II, or both myotoxins previously incubated with neutralizing antibody showed inhibition of the toxin-induced myotoxicity. These results reveal that the chemical modification of the phospholipases A2 (PLA2) diminished their toxicity but did not alter their antigenicity. This observation indicates that the modified PLA2 may provide a biotechnological tool to attenuate the toxicity of the crude venom, by improving the production of antibodies and decreasing the local toxic effects of this poisonous substance in animals used to produce antivenom. PMID:24901004

  16. Fabrication of stainless steel foil utilizing chromized steel strip

    NASA Astrophysics Data System (ADS)

    Loria, Edward A.

    1980-10-01

    Stainless steel foil has properties which are, in many respects, unmatched by alternative thin films. The high strength to weight ratio and resistance to corrosion and oxidation at elevated temperatures are generally advantageous. The aerospace 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 appropriate for the recuperator or heat exchanger and this product has also been used in honeycomb and truss-core structures. Further, such foil has been employed as a wrap to protect tool steel parts from contamination during heat treating. A large part of the high cost of producing stainless steel foil by rolling is due to the complicated and expensive rolling mill and annealing equipment involved. A method will be described which produces (solid) stainless steel foil from chromized (coated) steel which can be cheaper than the conventional processing stainless steel, such as Type 430, from ingot to foil. Also, the material is more ductile and less work hardenable during processing to foil and consequently intermediate annealing treatments are eliminated and scrap losses minimized.

  17. Steel Rattler

    NASA Astrophysics Data System (ADS)

    Trudo, Robert A.; Stotts, Larry G.

    1997-07-01

    Steel Rattler is a multi-phased project to determine the feasibility of using commercial off-the-shelf components in an advanced acoustic/seismic unattended ground sensor. This project is supported by the Defense Intelligence Agency through Sandia National Laboratories as the lead development agency. Steel Rattler uses advanced acoustic and seismic detection algorithms to categorize and identify various heavy vehicles down to the number of cylinders in the engine. This detection is accomplished with the capabilities of new, high-speed digital signal processors which analyze both acoustic and seismic data. The resulting analysis is compared against an onboard library of known vehicles and a statistical match is determined. An integrated thermal imager is also employed to capture digital thermal images for subsequent compression and transmission. Information acquired by Steel Rattler in the field is transmitted in small packets by a built-in low-power satellite communication system. The ground station receivers distribute the coded information to multiple analysis sites where the information is reassembled into coherent messages and images.

  18. Microstructural characterization during the hot deformation of 1.17C-11.3Cr-1.48V-2.24W-1.35Mo ledeburitic tool steel

    SciTech Connect

    Vecko Pirtovsek, T.; Kugler, G.; Godec, M.; Tercelj, M.

    2011-02-15

    The hot-deformation behavior of 1.17C-11.3Cr-1.48V-2.24W-1.35Mo tool steel was studied. Hot-compression tests were carried out in the temperature range of 850-1200 {sup o}C, at strain rates in the range of 0.001-6 s{sup -1}, and field-emission scanning electron microscope and optical microscopy were used for the microstructural characterization, which revealed a very complex precipitation of carbides that depends on the soaking temperature, the soaking time, the stress state, the deformation temperature as well as on the strain rate. A procedure for determining an appropriate soaking temperature, which enables an extension of the safe hot-working range, was developed. The soaking temperature and the time are the key factors controlling the hot workability. A study of the dissolution of ledeburitic carbides showed that there is a limit fraction to which the carbides could be dissolved prior to hot working without any negative influence on the hot workability. A revision of the general opinion about the influence of non-dissolved carbides on the hot workability is given. - Research Highlights: {yields} Procedure for determining of optimal soaking temperature is given. {yields} Apparent activation energies for three temperature and strain rate ranges are given. {yields} And Q at lower T and are increased due to higher amount of secondary carbides. {yields} Optimal fraction of dissolved carbides prior deformation increases hot workability.

  19. Rapid tooling for functional prototyping of metal mold processes: Literature review on cast tooling

    SciTech Connect

    Baldwin, M.D.; Hochanadel, P.W.

    1995-11-01

    This report is a literature review on cast tooling with the general focus on AISI H13 tool steel. The review includes processing of both wrought and cast H13 steel along with the accompanying microstructures. Also included is the incorporation of new rapid prototyping technologies, such as Stereolithography and Selective Laser Sintering, into the investment casting of tool steel. The limiting property of using wrought or cast tool steel for die casting is heat checking. Heat checking is addressed in terms of testing procedures, theories regarding the mechanism, and microstructural aspects related to the cracking.

  20. 77 FR 264 - Certain Cut-To-Length Carbon-Quality Steel Plate From India, Indonesia, and the Republic of Korea...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-04

    ... ASTM A710 and A736 or their proprietary equivalents; (4) abrasion-resistant steels (i.e., USS AR 400... equivalents; (6) ball bearing steels; (7) tool steels; and (8) silicon manganese steel or silicon electric... International Trade Administration Certain Cut-To-Length Carbon-Quality Steel Plate From India, Indonesia,...

  1. Friction Stir Spot Welding of Advanced High Strength Steels

    SciTech Connect

    Hovanski, Yuri; Santella, M. L.; Grant, Glenn J.

    2009-12-28

    Friction stir spot welding was used to join two advanced high-strength steels using polycrystalline cubic boron nitride tooling. Numerous tool designs were employed to study the influence of tool geometry on weld joints produced in both DP780 and a hot-stamp boron steel. Tool designs included conventional, concave shouldered pin tools with several pin configurations; a number of shoulderless designs; and a convex, scrolled shoulder tool. Weld quality was assessed based on lap shear strength, microstructure, microhardness, and bonded area. Mechanical properties were functionally related to bonded area and joint microstructure, demonstrating the necessity to characterize processing windows based on tool geometry.

  2. Friction Stir Spot Welding of Advanced High Strength Steels

    SciTech Connect

    Santella, Michael L; Hovanski, Yuri; Grant, Glenn J; Frederick, D Alan; Dahl, Michael E

    2009-02-01

    Friction stir spot welding was used to join two advanced high-strength steels using polycrystalline cubic boron nitride tooling. Numerous tool designs were employed to study the influence of tool geometry on weld joints produced in both DP780 and a hot-stamp boron steel. Tool designs included conventional, concave shouldered pin tools with several pin configurations; a number of shoulderless designs; and a convex, scrolled shoulder tool. Weld quality was assessed based on lap shear strength, microstructure, microhardness, and bonded area. Mechanical properties were functionally related to bonded area and joint microstructure, demonstrating the necessity to characterize processing windows based on tool geometry.

  3. Finite Element Analysis for Imaging Steel Bars Placed Under a Mild Steel Boundary Using Eddy Current Techniques

    SciTech Connect

    Hussin, H.; Zaid, M.; Gaydecki, P.; El-Madaani, F.; Fernandes, B.

    2006-03-06

    This paper reports on recent modelling results obtained using finite-element analysis for penetrating a magnetic field through a 2 mm steel boundary. The object is to detect 16 mm steel bars placed under mild steel boundaries at different operating frequencies. To penetrate thicker steel boundaries and increase the depth penetration, a different configuration based on remote field eddy currents (RFEC) has been modelled.

  4. Supertough Stainless Bearing Steel

    NASA Technical Reports Server (NTRS)

    Olson, Gregory B.

    1995-01-01

    Composition and processing of supertough stainless bearing steel designed with help of computer-aided thermodynamic modeling. Fracture toughness and hardness of steel exceeds those of other bearing steels like 440C stainless bearing steel. Developed for service in fuel and oxidizer turbopumps on Space Shuttle main engine. Because of strength and toughness, also proves useful in other applications like gears and surgical knives.

  5. 77 FR 263 - Certain Cut-To-Length Carbon-Quality Steel Plate From Italy and Japan: Revocation of Antidumping...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-04

    ...) abrasion-resistant steels (i.e., USS AR 400, USS AR 500); (5) products made to ASTM A202, A225, A514 grade S, A517 grade S, or their proprietary equivalents; (6) ball bearing steels; (7) tool steels; and (8... International Trade Administration Certain Cut-To-Length Carbon-Quality Steel Plate From Italy and...

  6. Retained Austenite Decomposition and Carbide Formation During Tempering a Hot-Work Tool Steel X38CrMoV5-1 Studied by Dilatometry and Atom Probe Tomography

    NASA Astrophysics Data System (ADS)

    Lerchbacher, Christoph; Zinner, Silvia; Leitner, Harald

    2012-12-01

    The microstructural development of a hot-work tool steel X38CrMoV5-1 during continuous heating to tempering temperature has been investigated with the focus on the decomposition of retained austenite (Stage II) and carbide formation (Stages III and IV). Investigations have been carried out after heating to 673.15 K, 773.15 K, 883.15 K (400 °C, 500 °C, 610 °C) and after a dwell time of 600 seconds at 883.15 K (610 °C). Dilatometry and atom probe tomography were used to identify tempering reactions. A distinctive reaction takes place between 723.15 K and 823.15 K (450 °C and 550 °C) which is determined to be the formation of M3C from transition carbides. Stage II could be evidenced with the atom probe results and indirectly with dilatometry, indicating the formation of new martensite during cooling. Retained austenite decomposition starts with the precipitation of alloy carbides formed from nanometric interlath retained austenite films which are laminary arranged and cause a reduction of the carbon content within the retained austenite. Preceding enrichment of substitutes at the matrix/carbide interface in the early stages of Cr7C3 alloy carbide formation could be visualised on the basis of coarse M3C carbides within the matrix. Atom probe tomography has been found to be very useful to complement dilatational experiments in order to characterise and identify microstructural changes.

  7. Microstructural characterization in dissimilar friction stir welding between 304 stainless steel and st37 steel

    SciTech Connect

    Jafarzadegan, M.; Feng, A.H.; Abdollah-zadeh, A.; Saeid, T.; Shen, J.; Assadi, H.

    2012-12-15

    In the present study, 3 mm-thick plates of 304 stainless steel and st37 steel were welded together by friction stir welding at a welding speed of 50 mm/min and tool rotational speed of 400 and 800 rpm. X-ray diffraction test was carried out to study the phases which might be formed in the welds. Metallographic examinations, and tensile and microhardness tests were used to analyze the microstructure and mechanical properties of the joint. Four different zones were found in the weld area except the base metals. In the stir zone of the 304 stainless steel, a refined grain structure with some features of dynamic recrystallization was evidenced. A thermomechanically-affected zone was characterized on the 304 steel side with features of dynamic recovery. In the other side of the stir zone, the hot deformation of the st37 steel in the austenite region produced small austenite grains and these grains transformed to fine ferrite and pearlite and some products of displacive transformations such as Widmanstatten ferrite and martensite by cooling the material after friction stir welding. The heat-affected zone in the st37 steel side showed partially and fully refined microstructures like fusion welding processes. The recrystallization in the 304 steel and the transformations in the st37 steel enhanced the hardness of the weld area and therefore, improved the tensile properties of the joint. - Highlights: Black-Right-Pointing-Pointer FSW produced sound welds between st37 low carbon steel and 304 stainless steel. Black-Right-Pointing-Pointer The SZ of the st37 steel contained some products of allotropic transformation. Black-Right-Pointing-Pointer The material in the SZ of the 304 steel showed features of dynamic recrystallization. Black-Right-Pointing-Pointer The finer microstructure in the SZ increased the hardness and tensile strength.

  8. New analytical tools and epidemiological data for the identification of HbA2 borderline subjects in the screening for beta-thalassemia.

    PubMed

    Mosca, Andrea; Paleari, Renata; Galanello, Renzo; Sollaino, Carla; Perseu, Lucia; Demartis, Franca Rosa; Passarello, Cristina; Giambona, Antonino; Maggio, Aurelio

    2008-08-01

    The increase of HbA(2) is the most important feature in the identification of beta-thalassemia carriers. However, some carriers are difficult to identify, because the level of HbA(2) is not in the typical range. Few data are available concerning the prevalence of such unusual phenotypes, and knowing their expected prevalence could be helpful in detecting systematic drifts in the analytical systems for HbA(2) quantification. In this study we report a retrospective investigation in two centres with high prevalence of beta-thalassemia. The prevalence of borderline subjects was found to be 2.2 and 3.0%, respectively. The genotypes of a subgroup of these subjects were then analyzed and in about 25% of cases a mutation in the globin genes was identified. We conclude that the occurrence of HbA(2) borderline phenotypes is not a rare event. In order to obtain more accurate HbA(2) measurements the development of an international reference measurement system for HbA(2), based on quantitative peptide mapping, has been recently started. We believe that the innovative approach of our method could also be used as a model to develop accurate quantitative methods for other red cell proteins relevant to the biodynamic properties and the surface electrochemistry of erythrocytes.

  9. Ultrahigh carbon steels, Damascus steels, and superplasticity

    SciTech Connect

    Sherby, O.D.; Wadsworth, J.

    1997-04-01

    The processing properties of ultrahigh carbon steels (UHCSs) have been studied at Stanford University over the past twenty years. These studies have shown that such steels (1 to 2.1% C) can be made superplastic at elevated temperature and can have remarkable mechanical properties at room temperature. It was the investigation of these UHCSs that eventually brought us to study the myths, magic, and metallurgy of ancient Damascus steels, which in fact, were also ultrahigh carbon steels. These steels were made in India as castings, known as wootz, possibly as far back as the time of Alexander the Great. The best swords are believed to have been forged in Persia from Indian wootz. This paper centers on recent work on superplastic UHCSs and on their relation to Damascus steels. 32 refs., 6 figs.

  10. L-Asp is a useful tool in the purification of the ionotropic glutamate receptor A2 ligand-binding domain.

    PubMed

    Krintel, Christian; Frydenvang, Karla; Ceravalls de Rabassa, Anna; Kaern, Anne M; Gajhede, Michael; Pickering, Darryl S; Kastrup, Jette S

    2014-05-01

    In purification of the ionotropic glutamate receptor A2 (GluA2) ligand-binding domain (LBD), L-Glu-supplemented buffers have previously been used for protein stabilization during the procedure. This sometimes hampers structural studies of low-affinity ligands, because L-Glu is difficult to displace, despite extensive dialysis. Here, we show that L-Asp binds to full-length GluA2 with low affinity (Ki = 0.63 mM) and to the GluA2 LBD with even lower affinity (Ki = 2.6 mM), and we use differential scanning fluorimetry to show that L-Asp is able to stabilize the isolated GluA2 LBD. We also show that L-Asp can replace L-Glu during purification, providing both equal yields and purity of the resulting protein sample. Furthermore, we solved three structures of the GluA2 LBD in the presence of 7.5, 50 and 250 mM L-Asp. Surprisingly, with 7.5 mM L-Asp, the GluA2 LBD crystallized as a mixed dimer, with L-Glu being present in one subunit, and neither L-Asp nor L-Glu being present in the other subunit. Thus, residual L-Glu is retained from the expression medium. On the other hand, only L-Asp was found at the binding site when 50 or 250 mM L-Asp was used for crystallization. The binding mode observed for L-Asp at the GluA2 LBD is very similar to that described for L-Glu. Taking our findings together, we have shown that L-Asp can be used instead of L-Glu for ligand-dependent stabilization of the GluA2 LBD during purification. This will enable structural studies of low-affinity ligands for lead optimization in structure-based drug design. Structural data are available in the Protein Data Bank under accession numbers 4O3B (7.5 mM L-Asp), 4O3C (50 mM L-Asp), and 4O3A (250 mM L-Asp). © 2014 FEBS.

  11. The high impact of a milling atmosphere on steel contamination.

    PubMed

    Štefanić, Goran; Krehula, Stjepko; Štefanić, Ivka

    2013-10-18

    High-energy ball-milling in an oxidative atmosphere caused gradual transition of pure zincite into zinc ferrite due to the oxidation of steel contamination. The rate of contamination increased dramatically (>3×) in an inert atmosphere due to the abrasion of milling tools by the steel chips coming from it.

  12. The A2V mutation as a new tool for hindering Aβ aggregation: A neutron and x-ray diffraction study.

    PubMed

    Cantu', Laura; Colombo, Laura; Stoilova, Tatiana; Demé, Bruno; Inouye, Hideyo; Booth, Rachel; Rondelli, Valeria; Di Fede, Giuseppe; Tagliavini, Fabrizio; Del Favero, Elena; Kirschner, Daniel A; Salmona, Mario

    2017-07-14

    We have described a novel C-to-T mutation in the APP gene that corresponds to an alanine to valine substitution at position 673 in APP (A673V), or position 2 of the amyloid-β (Aβ) sequence. This mutation is associated with the early onset of AD-type dementia in homozygous individuals, whereas it has a protective effect in the heterozygous state. Correspondingly, we observed differences in the aggregation properties of the wild-type and mutated Aβ peptides and their mixture. We have carried out neutron diffraction (ND) and x-ray diffraction (XRD) experiments on magnetically-oriented fibers of Aβ1-28WT and its variant Aβ1-28A2V. The orientation propensity was higher for Aβ1-28A2V suggesting that it promotes the formation of fibrillar assemblies. The diffraction patterns by Aβ1-28WT and Aβ1-28A2V assemblies differed in shape and position of the equatorial reflections, suggesting that the two peptides adopt distinct lateral packing of the diffracting units. The diffraction patterns from a mixture of the two peptides differed from those of the single components, indicating the presence of structural interference during assembly and orientation. The lowest orientation propensity was observed for a mixture of Aβ1-28WT and a short N-terminal fragment, Aβ1-6A2V, which supports a role of Aβ's N-terminal domain in amyloid fibril formation.

  13. Clean Cast Steel Technology, Phase IV

    SciTech Connect

    Charles E. Bates

    2003-02-24

    The objective of the Clean Cast Steel Technology Program was to improve casting product quality by removing or minimizing oxide defects and to allow the production of higher integrity castings for high speed machining lines. Previous research has concentrated on macro-inclusions that break, chip, or crack machine tool cutters and drills and cause immediate shutdown of the machining lines. The overall goal of the project is to reduce the amount of surface macro-inclusions and improve the machinability of steel castings. Macro-inclusions and improve the machinability of steel castings. Macro-inclusions have been identified by industrial sponsors as a major barrier to improving the quality and marketability of steel castings.

  14. 75 FR 47777 - Certain Cut-to-Length Carbon-Quality Steel Plate Products From Italy: Final Results of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-09

    ..., by weight, respectively indicated: 1.80 percent of manganese, or 1.50 percent of silicon, or 1.00..., or their proprietary equivalents; (6) ball bearing steels; (7) tool steels; and (8) silicon...

  15. Water Powered Tools

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Space Spin-Offs, Inc. under a contract with Lewis Research Center and Marshall Space Flight Center produced a new water-powered saw that cuts through concrete and steel plate reducing danger of explosion or electric shock in rescue and other operations. In prototype unit efficient water-powered turbine drives an 8 inch diameter grinding disk at 6,600 rpm. Exhaust water cools disk and workpiece quenching any sparks produced by cutting head. At maximum power, tool easily cuts through quarter inch steel plate. Adapter heads for chain saws, impact wrenches, heavy duty drills, and power hack saws can be fitted.

  16. Comminuting irradiated ferritic steel

    DOEpatents

    Bauer, Roger E.; Straalsund, Jerry L.; Chin, Bryan A.

    1985-01-01

    Disclosed is a method of comminuting irradiated ferritic steel by placing the steel in a solution of a compound selected from the group consisting of sulfamic acid, bisulfate, and mixtures thereof. The ferritic steel is used as cladding on nuclear fuel rods or other irradiated components.

  17. Welding Rustproof Steels

    NASA Technical Reports Server (NTRS)

    Hoffmann, W

    1929-01-01

    The following experimental results will perhaps increase the knowledge of the process of welding rustproof steels. The experiments were made with two chrome-steel sheets and with two chrome-steel-nickel sheets having the composition shown in Table I.

  18. The effect of microstructure on abrasive wear of steel

    NASA Astrophysics Data System (ADS)

    Kešner, A.; Chotëborský, R.; Linda, M.

    2017-09-01

    Abrasive wear of agricultural tools is one of the biggest problems in currently being. The amount of abrasive wear, depending on the microstructure, has been investigated in this work. Steels 25CrMo4 and 51CrV4 were used in this work to determine the effect of the microstructure on the abrasive wear. These steels are commonly used for components that have to withstand abrasive wear.SEM analysis was used to detect the microstructure. The standardized ASTM G65 method was used to compare the abrasive wear of steels. The results show that the abrasive wear depends on the microstructure of steels.

  19. 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.

  20. Retractor Tool for Brain Surgery

    NASA Technical Reports Server (NTRS)

    Helms, R.; Hayes, T.

    1982-01-01

    Proposed brain-surgery tool has an octogonal fixture for positioning latex tube over incision. Eight stainless-steel wires embedded in latex extend to hold positioning fixture. Another eight are also embedded in the latex. Concentric sleeves are successively inserted into expandable latex tube. The first sleeve is placed over a solid rod. Last sleeve is a stainless-steel tube 1 inch in diameter. It is overcoated with Teflon (or equivalent) material.

  1. Friction stir processing on carbon steel

    SciTech Connect

    Tarasov, Sergei Yu.; Melnikov, Alexander G.; Rubtsov, Valery E.

    2014-11-14

    Friction stir processing of medium carbon steel samples has been carried out using a milling machine and tools made of cemented tungsten carbide. Samples have been machined from 40 and 40X steels. The tools have been made in the shape of 5×5×1.5 mm and 3×3×1.5 mm tetrahedrons. The microstructure of stirred zone has been obtained using the smaller tool and consists of fine recrystallized 2-3 μm grains, whereas the larger tool has produced the 'onion-like' structures comprising hard quenched 'white' 500-600 MPa layers with 300-350 MPa interlayers of bainite needles. The mean values of wear intensity obtained after measuring the wear scar width were 0.02 mm/m and 0.001 mm/m for non-processed and processed samples, respectively.

  2. The steel scrap age.

    PubMed

    Pauliuk, Stefan; Milford, Rachel L; Müller, Daniel B; Allwood, Julian M

    2013-04-02

    Steel production accounts for 25% of industrial carbon emissions. Long-term forecasts of steel demand and scrap supply are needed to develop strategies for how the steel industry could respond to industrialization and urbanization in the developing world while simultaneously reducing its environmental impact, and in particular, its carbon footprint. We developed a dynamic stock model to estimate future final demand for steel and the available scrap for 10 world regions. Based on evidence from developed countries, we assumed that per capita in-use stocks will saturate eventually. We determined the response of the entire steel cycle to stock saturation, in particular the future split between primary and secondary steel production. During the 21st century, steel demand may peak in the developed world, China, the Middle East, Latin America, and India. As China completes its industrialization, global primary steel production may peak between 2020 and 2030 and decline thereafter. We developed a capacity model to show how extensive trade of finished steel could prolong the lifetime of the Chinese steelmaking assets. Secondary steel production will more than double by 2050, and it may surpass primary production between 2050 and 2060: the late 21st century can become the steel scrap age.

  3. Machine Tool Software

    NASA Technical Reports Server (NTRS)

    1988-01-01

    A NASA-developed software package has played a part in technical education of students who major in Mechanical Engineering Technology at William Rainey Harper College. Professor Hack has been using (APT) Automatically Programmed Tool Software since 1969 in his CAD/CAM Computer Aided Design and Manufacturing curriculum. Professor Hack teaches the use of APT programming languages for control of metal cutting machines. Machine tool instructions are geometry definitions written in APT Language to constitute a "part program." The part program is processed by the machine tool. CAD/CAM students go from writing a program to cutting steel in the course of a semester.

  4. Methods of forming steel

    DOEpatents

    Branagan, Daniel J.; Burch, Joseph V.

    2001-01-01

    In one aspect, the invention encompasses a method of forming a steel. A metallic glass is formed and at least a portion of the glass is converted to a crystalline steel material having a nanocrystalline scale grain size. In another aspect, the invention encompasses another method of forming a steel. A molten alloy is formed and cooled the alloy at a rate which forms a metallic glass. The metallic glass is devitrified to convert the glass to a crystalline steel material having a nanocrystalline scale grain size. In yet another aspect, the invention encompasses another method of forming a steel. A first metallic glass steel substrate is provided, and a molten alloy is formed over the first metallic glass steel substrate to heat and devitrify at least some of the underlying metallic glass of the substrate.

  5. 75 FR 10207 - Certain Cut-to-Length Carbon-Quality Steel Plate From the Republic of Korea: Final Results of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-05

    ... manganese, or 1.50 percent of silicon, or 1.00 percent of copper, or 0.50 percent of aluminum, or 1.25... bearing steels; (7) tool steels; and (8) silicon manganese steel or silicon electric steel. Imports...

  6. Friction Stir Spot Welding of Advanced High Strength Steels

    SciTech Connect

    Hovanski, Yuri; Grant, Glenn J.; Santella, M. L.

    2009-11-13

    Friction stir spot welding techniques were developed to successfully join several advanced high strength steels. Two distinct tool materials were evaluated to determine the effect of tool materials on the process parameters and joint properties. Welds were characterized primarily via lap shear, microhardness, and optical microscopy. Friction stir spot welds were compared to the resistance spot welds in similar strength alloys by using the AWS standard for resistance spot welding high strength steels. As further comparison, a primitive cost comparison between the two joining processes was developed, which included an evaluation of the future cost prospects of friction stir spot welding in advanced high strength steels.

  7. Using social and mobile tools for weight loss in overweight and obese young adults (Project SMART): a 2 year, parallel-group, randomised, controlled trial.

    PubMed

    Godino, Job G; Merchant, Gina; Norman, Gregory J; Donohue, Michael C; Marshall, Simon J; Fowler, James H; Calfas, Karen J; Huang, Jeannie S; Rock, Cheryl L; Griswold, William G; Gupta, Anjali; Raab, Fredric; Fogg, B J; Robinson, Thomas N; Patrick, Kevin

    2016-09-01

    Few weight loss interventions are evaluated for longer than a year, and even fewer employ social and mobile technologies commonly used among young adults. We assessed the efficacy of a 2 year, theory-based, weight loss intervention that was remotely and adaptively delivered via integrated user experiences with Facebook, mobile apps, text messaging, emails, a website, and technology-mediated communication with a health coach (the SMART intervention). In this parallel-group, randomised, controlled trial, we enrolled overweight or obese college students (aged 18-35 years) from three universities in San Diego, CA, USA. Participants were randomly assigned (1:1) to receive either the intervention (SMART intervention group) or general information about health and wellness (control group). We used computer-based permuted-block randomisation with block sizes of four, stratified by sex, ethnicity, and college. Participants, study staff, and investigators were masked until the intervention was assigned. The primary outcome was objectively measured weight in kg at 24 months. Differences between groups were evaluated using linear mixed-effects regression within an intention-to-treat framework. Objectively measured weight at 6, 12, and 18 months was included as a secondary outcome. The trial is registered with ClinicalTrials.gov, number NCT01200459. Between May 18, 2011, and May 17, 2012, 404 individuals were randomly assigned to the intervention (n=202) or control (n=202). Participants' mean (SD) age was 22·7 (3·8) years. 284 (70%) participants were female and 125 (31%) were Hispanic. Mean (SD) body-mass index at baseline was 29·0 (2·8) kg/m(2). At 24 months, weight was assessed in 341 (84%) participants, but all 404 were included in analyses. Weight, adjusted for sex, ethnicity, and college, was not significantly different between the groups at 24 months (-0·79 kg [95% CI -2·02 to 0·43], p=0·204). However, weight was significantly less in the intervention group

  8. Development of Next Generation Heating System for Scale Free Steel Reheating

    SciTech Connect

    Dr. Arvind C. Thekdi

    2011-01-27

    The work carried out under this project includes development and design of components, controls, and economic modeling tools that would enable the steel industry to reduce energy intensity through reduction of scale formation during the steel reheating process. Application of scale free reheating offers savings in energy used for production of steel that is lost as scale, and increase in product yield for the global steel industry. The technology can be applied to a new furnace application as well as retrofit design for conversion of existing steel reheating furnaces. The development work has resulted in the knowledge base that will enable the steel industry and steel forging industry us to reheat steel with 75% to 95% reduction in scale formation and associated energy savings during the reheating process. Scale reduction also results in additional energy savings associated with higher yield from reheat furnaces. Energy used for steel production ranges from 9 MM Btu/ton to 16.6 MM Btu/ton or the industry average of approximately 13 MM Btu/ton. Hence, reduction in scale at reheating stage would represent a substantial energy reduction for the steel industry. Potential energy savings for the US steel industry could be in excess of 25 Trillion Btu/year when the technology is applied to all reheating processes. The development work has resulted in new design of reheating process and the required burners and control systems that would allow use of this technology for steel reheating in steel as well as steel forging industries.

  9. 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.

  10. Maraging Steel Machining Improvements

    DTIC Science & Technology

    2007-04-23

    APR 2007 2. REPORT TYPE Technical, Success Story 3. DATES COVERED 01-12-2006 to 23-04-2007 4. TITLE AND SUBTITLE Maraging Steel Machining...consumers of cobalt-strengthened maraging steel . An increase in production requires them to reduce the machining time of certain operations producing... maraging steel ; Success Stories 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 1 18. NUMBER OF PAGES 1 19a. NAME OF RESPONSIBLE

  11. Welding irradiated stainless steel

    SciTech Connect

    Kanne, W.R. Jr.; Chandler, G.T.; Nelson, D.Z.; Franco-Ferreira, E.A.

    1993-12-31

    Conventional welding processes produced severe underbead cracking in irradiated stainless steel containing 1 to 33 appm helium from n,a reactions. A shallow penetration overlay technique was successfully demonstrated for welding irradiated stainless steel. The technique was applied to irradiated 304 stainless steel that contained 10 appm helium. Surface cracking, present in conventional welds made on the same steel at the same and lower helium concentrations, was eliminated. Underbead cracking was minimal compared to conventional welding methods. However, cracking in the irradiated material was greater than in tritium charged and aged material at the same helium concentrations. The overlay technique provides a potential method for repair or modification of irradiated reactor materials.

  12. Conventional machining of ESR 4340 steel

    NASA Astrophysics Data System (ADS)

    Niji, K. K.

    1980-07-01

    This program involved the study of conventional machining of heat treated ESR 4340 steel (Rc 54-57). Initial effort involved a survey of available data regarding the machining of high strength steels with hardnesses of Rc 50 and above. A machining program was conducted, determining optimum tools and conditions for turning, drilling, face milling, end milling, and grinding operations. Effects of various parameters includng cutting speeds, feeds, depths of cut, and cutting fluids on tool life was determined. All the operations were found to be extremely difficult and applicaton of conventional procedures is not feasible. Tool lives remained short despite reductions in speeds and feeds. Conventional grinding methods induced detrimental residual tensile stresses along the surface, resulting in cracking, lapping, and untempered martensitic structures. Low stress grinding techniques were found to be applicable to this material when proper dressing procedures and reduced rates were used.

  13. Solidification Sequence of Spray-Formed Steels

    NASA Astrophysics Data System (ADS)

    Zepon, Guilherme; Ellendt, Nils; Uhlenwinkel, Volker; Bolfarini, Claudemiro

    2016-02-01

    Solidification in spray-forming is still an open discussion in the atomization and deposition area. This paper proposes a solidification model based on the equilibrium solidification path of alloys. The main assumptions of the model are that the deposition zone temperature must be above the alloy's solidus temperature and that the equilibrium liquid fraction at this temperature is reached, which involves partial remelting and/or redissolution of completely solidified droplets. When the deposition zone is cooled, solidification of the remaining liquid takes place under near equilibrium conditions. Scanning electron microscopy (SEM) and optical microscopy (OM) were used to analyze the microstructures of two different spray-formed steel grades: (1) boron modified supermartensitic stainless steel (SMSS) and (2) D2 tool steel. The microstructures were analyzed to determine the sequence of phase formation during solidification. In both cases, the solidification model proposed was validated.

  14. Application of RST in the steel industry

    NASA Astrophysics Data System (ADS)

    Raman, R. V.; Maringer, R. E.

    1982-05-01

    The rapid solidification technology (RST) involves quenching molten metals at rates of perhaps 102 to 1010 degrees C per second. First reported in 1960, RST has experienced rapid growth during the last decade and is now established on the commercial market-place. This has resulted from the simple facts that unusual properties result from RST, that relatively easy techniques are available to produce large quantities of material, and that applications for these materials have been recognized. Ferrous-base materials produced by RST methods include staple fibers of mild and stainless steel for incorporation into concrete and castable refractories, powder metallurgy tool steels, and amorphous strip for power transformers. Research results suggest that RST will have a strong continuing influence on ferrous powder metallurgy, on the direct casting of strip and foil of carbon and stainless steel, and on core materials for motor and transformers.

  15. The Steel Band.

    ERIC Educational Resources Information Center

    Weil, Bruce

    1996-01-01

    Describes studying the steel drum, an import from Trinidad, as an instrument of intellectual growth. Describes how developing a steel drum band provided Montessori middle school students the opportunity to experience some important feelings necessary to emotional growth during this difficult age: competence, usefulness, independence, and…

  16. Steel Industry Wastes.

    ERIC Educational Resources Information Center

    Schmidtke, N. W.; Averill, D. W.

    1978-01-01

    Presents a literature review of wastes from steel industry, covering publications of 1976-77. This review covers: (1) coke production; (2) iron and steel production; (3) rolling operations; and (4) surface treatment. A list of 133 references is also presented. (NM)

  17. High Nitrogen Stainless Steel

    DTIC Science & Technology

    2011-07-19

    Hydrogen Embrittlement in Steel by the Increment Loading Technique. Fractography: After the stress-life fatigue tests, the fracture surface morphology...study was conducted to clarify the mechanical properties and stress corrosion cracking (SCC) resistance of high nitrogen stainless steel (HNSS) plates...Corrosion Cracking 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE PERSON

  18. Steel Industry Wastes.

    ERIC Educational Resources Information Center

    Schmidtke, N. W.; Averill, D. W.

    1978-01-01

    Presents a literature review of wastes from steel industry, covering publications of 1976-77. This review covers: (1) coke production; (2) iron and steel production; (3) rolling operations; and (4) surface treatment. A list of 133 references is also presented. (NM)

  19. Combining selectivity and affinity predictions using an integrated Support Vector Machine (SVM) approach: An alternative tool to discriminate between the human adenosine A(2A) and A(3) receptor pyrazolo-triazolo-pyrimidine antagonists binding sites.

    PubMed

    Michielan, Lisa; Bolcato, Chiara; Federico, Stephanie; Cacciari, Barbara; Bacilieri, Magdalena; Klotz, Karl-Norbert; Kachler, Sonja; Pastorin, Giorgia; Cardin, Riccardo; Sperduti, Alessandro; Spalluto, Giampiero; Moro, Stefano

    2009-07-15

    G Protein-coupled receptors (GPCRs) selectivity is an important aspect of drug discovery process, and distinguishing between related receptor subtypes is often the key to therapeutic success. Nowadays, very few valuable computational tools are available for the prediction of receptor subtypes selectivity. In the present study, we present an alternative application of the Support Vector Machine (SVM) and Support Vector Regression (SVR) methodologies to simultaneously describe both A(2A)R versus A(3)R subtypes selectivity profile and the corresponding receptor binding affinities. We have implemented an integrated application of SVM-SVR approach, based on the use of our recently reported autocorrelated molecular descriptors encoding for the Molecular Electrostatic Potential (autoMEP), to simultaneously discriminate A(2A)R versus A(3)R antagonists and to predict their binding affinity to the corresponding receptor subtype of a large dataset of known pyrazolo-triazolo-pyrimidine analogs. To validate our approach, we have synthetized 51 new pyrazolo-triazolo-pyrimidine derivatives anticipating both A(2A)R/A(3)R subtypes selectivity and receptor binding affinity profiles.

  20. EAST ELEVATION, LTV STEEL (FORMERLY REPUBLIC STEEL), 8" BAR MILL, ...

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

    EAST ELEVATION, LTV STEEL (FORMERLY REPUBLIC STEEL), 8" BAR MILL, BUFFALO PLANT. VIEW LOOKING SOUTHWEST FROM ROLL SHOP. 8" BAR MILL DESIGNED AND BUILT BY DONNER STEEL CO. (PREDECESSOR OF REPUBLIC), 1919-1920. FOR DESCRIPTION OF ORIGINAL MILL SEE "IRON AGE", 116\\4 (23 JULY 1925): 201-204. - LTV Steel, 8-inch Bar Mill, Buffalo Plant, Buffalo, Erie County, NY

  1. Impact toughness of irradiated reduced-activation ferritic steels*1

    NASA Astrophysics Data System (ADS)

    Klueh, R. L.; Alexander, D. J.

    1994-09-01

    Eight chromium-tungsten steels ranging from 2.25 to 12 wt% Cr were irradiated at 365°C to 13-14 dpa in the Fast Flux Test Facility. Post irradiation Charpy impact tests showed a loss of toughness for all steels, as measured by an increase in the ductile-brittle transition temperature (DBTT) and a decrease in the upper-shelf energy. The most irradiation-resistant steels were two 9% Cr steels: the DBTT of a 9Cr-2W-0.25V-0.1C steel increased 29°C, and for the same composition with an addition of 0.07% Ta the DBTT increased only 15°C. This is the smallest shift ever observed for such a steel irradiated to these levels. The other steels developed shifts in DBTT of 100 to 300°C. A 2.25% Cr steel with 2% W, 0.25% V, and 0.1% C was less severely affected by irradiation than 2.25% Cr steels with 0.25% V and no tungsten, 2% W and no vanadium, and with 1% W and 0.25% V. Irradiation resistance appears to be associated with microstructure, and microstructural manipulation may lead to improved properties.

  2. Nuclear transmutation in steels

    NASA Astrophysics Data System (ADS)

    Belozerova, A. R.; Shimanskii, G. A.; Belozerov, S. V.

    2009-05-01

    The investigations of the effects of nuclear transmutation in steels that are widely used in nuclear power and research reactors and in steels that are planned for the application in thermonuclear fusion plants, which are employed under the conditions of a prolonged action of neutron irradiation with different spectra, made it possible to study the effects of changes in the isotopic and chemical composition on the tendency of changes in the structural stability of these steels. For the computations of nuclear transmutation in steels, we used a program complex we have previously developed on the basis of algorithms for constructing branched block-type diagrams of nuclide transformations and for locally and globally optimizing these diagrams with the purpose of minimizing systematic errors in the calculation of nuclear transmutation. The dependences obtained were applied onto a Schaeffler diagram for steels used for structural elements of reactors. For the irradiation in fission reactors, we observed only a weak influence of the effects of nuclear transmutation in steels on their structural stability. On the contrary, in the case of irradiation with fusion neutrons, a strong influence of the effects of nuclear transmutation in steels on their structural stability has been noted.

  3. Damascus steel ledeburite class

    NASA Astrophysics Data System (ADS)

    Sukhanov, D. A.; Arkhangelsky, L. B.; Plotnikova, N. V.

    2017-02-01

    Discovered that some of blades Damascus steel has an unusual nature of origin of the excess cementite, which different from the redundant phases of secondary cementite, cementite of ledeburite and primary cementite in iron-carbon alloys. It is revealed that the morphological features of separate particles of cementite in Damascus steels lies in the abnormal size of excess carbides having the shape of irregular prisms. Considered three hypotheses for the formation of excess cementite in the form of faceted prismatic of excess carbides. The first hypothesis is based on thermal fission of cementite of a few isolated grains. The second hypothesis is based on the process of fragmentation cementite during deformation to the separate the pieces. The third hypothesis is based on the transformation of metastable cementite in the stable of angular eutectic carbide. It is shown that the angular carbides are formed within the original metastable colony ledeburite, so they are called “eutectic carbide”. It is established that high-purity white cast iron is converted into of Damascus steel during isothermal soaking at the annealing. It was revealed that some of blades Damascus steel ledeburite class do not contain in its microstructure of crushed ledeburite. It is shown that the pattern of carbide heterogeneity of Damascus steel consists entirely of angular eutectic carbides. Believe that Damascus steel refers to non-heat-resistant steel of ledeburite class, which have similar structural characteristics with semi-heat-resistant die steel or heat-resistant high speed steel, differing from them only in the nature of excess carbide phase.

  4. Friction Stir Welding of Steel Alloys

    NASA Technical Reports Server (NTRS)

    Ding, R. Jeffrey; Munafo, Paul M. (Technical Monitor)

    2001-01-01

    The friction stir welding process has been developed primarily for the welding of aluminum alloys. Other higher melting allows such, as steels are much more difficult to join. Special attention must be given to pin tool material selection and welding techniques. This paper addresses the joining of steels and other high melting point materials using the friction stir welding process. Pin tool material and welding parameters will be presented. Mechanical properties of weldments will also be presented. Significance: There are many applications for the friction stir welding process other than low melting aluminum alloys. The FSW process can be expanded for use with high melting alloys in the pressure vessel, railroad and ship building industries.

  5. Friction Stir Welding of Steel Alloys

    NASA Technical Reports Server (NTRS)

    Ding, R. Jeffrey; Munafo, Paul M. (Technical Monitor)

    2001-01-01

    The friction stir welding process has been developed primarily for the welding of aluminum alloys. Other higher melting allows such, as steels are much more difficult to join. Special attention must be given to pin tool material selection and welding techniques. This paper addresses the joining of steels and other high melting point materials using the friction stir welding process. Pin tool material and welding parameters will be presented. Mechanical properties of weldments will also be presented. Significance: There are many applications for the friction stir welding process other than low melting aluminum alloys. The FSW process can be expanded for use with high melting alloys in the pressure vessel, railroad and ship building industries.

  6. Quantification of indium in steel using PIXE

    NASA Astrophysics Data System (ADS)

    Oliver, A.; Miranda, J.; Rickards, J.; Cheang, J. C.

    1989-04-01

    The quantitative analysis of steel for endodontics tools was carried out using low-energy protons (≤ 700 keV). A computer program for a thick-target analysis which includes enhancement due to secondary fluorescence was used. In this experiment the L-lines of indium are enhanced due to the proximity of other elements' K-lines to the indium absorption edge. The results show that the ionization cross section expression employed to evaluate this magnitude is important.

  7. Steel Pickling Inspection Checklist

    EPA Pesticide Factsheets

    Checklist to establish whether a facility or operations within a facility are subject to and are in compliance with 40 C.F.R Part 63 Subpart CCC (Steel Pickling—HCl Process Facilities and Hydrochloric Acid Regeneration Plants NESHAP).

  8. Structural Amorphous Steels

    NASA Astrophysics Data System (ADS)

    Lu, Z. P.; Liu, C. T.; Thompson, J. R.; Porter, W. D.

    2004-06-01

    Recent advancement in bulk metallic glasses, whose properties are usually superior to their crystalline counterparts, has stimulated great interest in fabricating bulk amorphous steels. While a great deal of effort has been devoted to this field, the fabrication of structural amorphous steels with large cross sections has remained an alchemist’s dream because of the limited glass-forming ability (GFA) of these materials. Here we report the discovery of structural amorphous steels that can be cast into glasses with large cross-section sizes using conventional drop-casting methods. These new steels showed interesting physical, magnetic, and mechanical properties, along with high thermal stability. The underlying mechanisms for the superior GFA of these materials are discussed.

  9. Cobalt free maraging steel

    SciTech Connect

    Floreen, S.

    1984-04-17

    The subject invention is directed to ferrous-base alloys, particularly to a cobalt-free maraging steel of novel chemistry characterized by a desired combination of strength and toughness, notwithstanding that cobalt is non-essential.

  10. Glass Stronger than Steel

    DOE R&D Accomplishments Database

    Yarris, Lynn

    2011-03-28

    A new type of damage-tolerant metallic glass, demonstrating a strength and toughness beyond that of steel or any other known material, has been developed and tested by a collaboration of researchers from Berkeley Lab and Caltech.

  11. Fffect of heat treatment conditions on structure and properties of high-speed steel

    NASA Astrophysics Data System (ADS)

    Nikolaeva, E. P.; Vlasov, D. B.

    2017-02-01

    High-speed steels made by powder and traditional metallurgical technology have been investigated. These steels are used for manufacturing of metalworking tools. Powder high-speed steels have a large safety margin and a high level of mechanical properties. Mechanical properties and the structure of steels S390 MICROCLEAN® and Fe-9%W-4%Mo-8%Co were compared after their hardening heat treatment. The composition of the carbides was determined by x-ray phase analysis. Residual stresses of the finished cutters were determined. It was shown that the mechanical properties of steels have been determined by the phase composition and the degree of carbides dispersion. The dependence of the microstructure and the high-speed steels phase composition on heat treatment conditions was identified. The conclusion about structure control effectiveness in the adjustment of heat treatment conditions of high speed steels was made.

  12. Acoustic emission from single point machining: Part 2, Signal changes with tool wear

    SciTech Connect

    Heiple, C.R.; Carpenter, S.H.; Armentrout, D.L.; McManigle, A.P.

    1989-01-01

    Changes in acoustic emission signal characteristics with tool wear were monitored during single point machining of 4340 steel and Ti-6Al-4V heat treated to several strength levels, 606l-T6 aluminum, 304 stainless steel, 17-4PH stainless steel, 410 stainless steel, lead, and teflon. No signal characteristic changed in the same way with tool wear for all materials tested. A single change in a particular AE signal characteristic with tool wear valid for all materials probably does not exist. Nevertheless, changes in various signal characteristic with wear for a given material may be sufficient to be used to monitor tool wear.

  13. Acoustic emission from single point machining: Part 2, Signal changes with tool wear. Revised

    SciTech Connect

    Heiple, C.R.; Carpenter, S.H.; Armentrout, D.L.; McManigle, A.P.

    1989-12-31

    Changes in acoustic emission signal characteristics with tool wear were monitored during single point machining of 4340 steel and Ti-6Al-4V heat treated to several strength levels, 606l-T6 aluminum, 304 stainless steel, 17-4PH stainless steel, 410 stainless steel, lead, and teflon. No signal characteristic changed in the same way with tool wear for all materials tested. A single change in a particular AE signal characteristic with tool wear valid for all materials probably does not exist. Nevertheless, changes in various signal characteristic with wear for a given material may be sufficient to be used to monitor tool wear.

  14. Life after Steel

    ERIC Educational Resources Information Center

    Mangan, Katherine

    2013-01-01

    Bobby Curran grew up in a working-class neighborhood in Baltimore, finished high school, and followed his grandfather's steel-toed bootprints straight to Sparrows Point, a 3,000-acre sprawl of industry on the Chesapeake Bay. College was not part of the plan. A gritty but well-paying job at the RG Steel plant was Mr. Curran's ticket to a secure…

  15. Joining Steel Armor - Intermix

    DTIC Science & Technology

    1979-03-01

    TARADCOM a d ki Lk A el B~ 0el RWET0 TECHNICAL REPORT NO. 12311 JOINING STEEL ARMOR - INTERMIX March 1979 U U * S* ’ "U .by B. . A.SCEV * U...authorized documents. O "if TECHNICAL REPORT NO. 12311 JOINING STEEL ARMOR - INTERMIX BY B. A. SCHEVO March 1979 AMS: 3197..6D.4329 TARADCOM ARMOR AND...Intermix Process ...... ........ 3 Test Procedures - Intermix Armor ........ ......... 4 Mock Hull ................. ..................... 5 Results

  16. Ferrium M54 Steel

    DTIC Science & Technology

    2015-03-18

    release; distribution is unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT Bare and Zn-14% Ni alloy coated Ferrium M54 steels were studied to...Ni alloy coating appears to provide the steel some protection against hydrogen embrittlement/SCC and corrosion fatigue in aqueous 3.5% NaCl...301-342-8069 Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. Z39-18 NAWCADPAX/TIM-2014/292 ii SUMMARY Bare and Zn-14% Ni alloy

  17. Life after Steel

    ERIC Educational Resources Information Center

    Mangan, Katherine

    2013-01-01

    Bobby Curran grew up in a working-class neighborhood in Baltimore, finished high school, and followed his grandfather's steel-toed bootprints straight to Sparrows Point, a 3,000-acre sprawl of industry on the Chesapeake Bay. College was not part of the plan. A gritty but well-paying job at the RG Steel plant was Mr. Curran's ticket to a secure…

  18. Articles comprising ferritic stainless steels

    SciTech Connect

    Rakowski, James M.

    2016-06-28

    An article of manufacture comprises a ferritic stainless steel that includes a near-surface region depleted of silicon relative to a remainder of the ferritic stainless steel. The article has a reduced tendency to form an electrically resistive silica layer including silicon derived from the steel when the article is subjected to high temperature oxidizing conditions. The ferritic stainless steel is selected from the group comprising AISI Type 430 stainless steel, AISI Type 439 stainless steel, AISI Type 441 stainless steel, AISI Type 444 stainless steel, and E-BRITE.RTM. alloy, also known as UNS 44627 stainless steel. In certain embodiments, the article of manufacture is a fuel cell interconnect for a solid oxide fuel cell.

  19. Waste product profile: Steel cans

    SciTech Connect

    Miller, C.

    1996-07-01

    Steel cans are made from tinplate steel, which is produced in basic oxygen furnaces. A thin layer of tin is applied to the can`s inner and outer surfaces to prevent rusting and protect food and beverage flavors. As a result, steel cans are often called tin cans. Steel mills are the largest market for steel cans. Integrated mills use the basic oxygen process to manufacture tinplate, appliances, car bodies, and steel framing. Electric arc furnaces use 100% scrap to produce steel shapes such as railroad ties and bridge spans. Electric arc furnaces are more geographically diverse and tend to have smaller capacities than basic oxygen furnaces. Detinners remove the tin from steel cans for resale to tin using industries. Continued decreases in the amount of tin used in steel cans has lessened the importance of this market. Foundries use scrap as a raw material in making castings and molds for industrial users.

  20. SOLID STATE JOINING OF MAGNESIUM TO STEEL

    SciTech Connect

    Jana, Saumyadeep; Hovanski, Yuri; Pilli, Siva Prasad; Field, David P.; Yu, Hao; Pan, Tsung-Yu; Santella, M. L.

    2012-06-04

    Friction stir welding and ultrasonic welding techniques were applied to join automotive magnesium alloys to steel sheet. The effect of tooling and process parameters on the post-weld microstructure, texture and mechanical properties was investigated. Static and dynamic loading were utilized to investigate the joint strength of both cast and wrought magnesium alloys including their susceptibility and degradation under corrosive media. The conditions required to produce joint strengths in excess of 75% of the base metal strength were determined, and the effects of surface coatings, tooling and weld parameters on weld properties are presented.

  1. Solid State Joining of Magnesium to Steel

    NASA Astrophysics Data System (ADS)

    Jana, Saumyadeep; Hovanski, Yuri; Pilli, Siva P.; Field, David P.; Yu, Hao; Pan, Tsung-Yu; Santella, M. L.

    Friction stir welding and ultrasonic welding techniques were applied to join automotive magnesium alloys to steel sheet. The effect of tooling and process parameters on the post-weld microstructure, texture and mechanical properties was investigated. Static and dynamic loading were utilized to investigate the joint strength of both cast and wrought magnesium alloys including their susceptibility and degradation under corrosive media. The conditions required to produce joint strengths in excess of 75% of the base metal strength were determined, and the effects of surface coatings, tooling and weld parameters on weld properties are presented.

  2. Castings, Steel, Homogenization of Steel Castings

    DTIC Science & Technology

    1942-12-05

    diffraction pattern of quenched and tempered steel castings. 2. Calculations based upon known diffusion rates show: A. Practical homogenizing heat ...will be largely eliminated by either the usual heating for nuenching or a homo- genizing treatment. C. Interdendritic segregation of sulfur will...26 Appendix A - History of the Heat Treatment and Composition of Centrifugal Gun Castings at W-tertown Ar- sen-.l. ..... ..................... 2

  3. Recent developments in turning hardened steels - A review

    NASA Astrophysics Data System (ADS)

    Sivaraman, V.; Prakash, S.

    2017-05-01

    Hard materials ranging from HRC 45 - 68 such as hardened AISI H13, AISI 4340, AISI 52100, D2 STL, D3 STEEL Steel etc., need super hard tool materials to machine. Turning of these hard materials is termed as hard turning. Hard turning makes possible direct machining of the hard materials and also eliminates the lubricant requirement and thus favoring dry machining. Hard turning is a finish turning process and hence conventional grinding is not required. Development of the new advanced super hard tool materials such as ceramic inserts, Cubic Boron Nitride, Polycrystalline Cubic Boron Nitride etc. enabled the turning of these materials. PVD and CVD methods of coating have made easier the production of single and multi layered coated tool inserts. Coatings of TiN, TiAlN, TiC, Al2O3, AlCrN over cemented carbide inserts has lead to the machining of difficult to machine materials. Advancement in the process of hard machining paved way for better surface finish, long tool life, reduced tool wear, cutting force and cutting temperatures. Micro and Nano coated carbide inserts, nanocomposite coated PCBN inserts, micro and nano CBN coated carbide inserts and similar developments have made machining of hardened steels much easier and economical. In this paper, broad literature review on turning of hardened steels including optimizing process parameters, cooling requirements, different tool materials etc., are done.

  4. Profiles in garbage: Steel cans

    SciTech Connect

    Miller, C.

    1998-02-01

    Steel mills are the largest market for steel cans. Integrated mills use the basic oxygen process to manufacture tinplate, appliances, car bodies, and steel framing. Electric arc furnaces use 100% scrap to produce steel shapes such as railroad ties and bridge spans. Electric arc furnaces are more geographically diverse and tend to have smaller capacities than basic oxygen furnaces. Detinners remove the tin from steel cans for resale to tin using industries. With less tin use in steel cans, the importance of the detinning market has declined substantially. Foundries use scrap as a raw material in making castings and molds for industrial users.

  5. View northwest, wharf A, sheet steel bulkhead, steel lift tower ...

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

    View northwest, wharf A, sheet steel bulkhead, steel lift tower - U.S. Coast Guard Sandy Hook Station, Western Docking Structure, West of intersection of Canfield Road & Hartshorne Drive, Highlands, Monmouth County, NJ

  6. Surface microanalytical studies of nitrogen ion-implanted steel

    NASA Astrophysics Data System (ADS)

    Dodd, Charles G.; Meeker, G. P.; Baumann, Scott M.; Norberg, James C.; Legg, Keith O.

    1985-03-01

    Five types of industrial steels, 1018, 52100, M-2, 440C, and 304 were ion implanted with nitrogen and subjected to surface microanalysis by three independent surface techniques: AES, RBS, and SIMS. The results provided understanding for earlier observations of the properties of various types of steel after nitrogen implantation. The steels that retained the most nitrogen and that have been reported to benefit the most in improved tribological properties from ion implantation were ferritic carbon and austenitic stainless steels, such as soft 1018 and 304, respectively. Heat-treated martensitic carbon steels such as 52100 and M-2 tool steel were found to retain the least nitrogen, and they have been reported to benefit less from nitrogen implantation; however, the interaction of transition metal carbides in M-2 with nitrogen has not been clarified. The data showed that 440C steel retained as much nitrogen as 1018 and 304, but treatment benefits may be limited to improvements in properties related to toughness and impact resistance.

  7. Replacement steel windows

    SciTech Connect

    Brown, M.A.; Condren, S.J.

    1999-07-01

    This paper presents the authors experiences in the investigation, design, and installation of replacement steel windows for two renovation projects at a major university in the northeast: a student residential complex and the law school. The authors review the construction of the existing walls (cast-in-place concrete barrier wall at the student residential complex and brick and stone masonry barrier wall at the law school), and the construction and performance of the original steel windows. To maintain the appearance of these architecturally significant buildings, the university elected to install replacement steel windows. The authors discuss special design consideration for steel windows (versus the more prevalent aluminum replacement window), including available window section profiles, corrosion protection, frame fabrication, and glazing design. The authors also review window flashing concepts they employed for the barrier wall construction, which has no drainage cavity. The authors summarize lessons learned during the window selection, design, fabrication, testing, and installation phases of the projects, and present recommendations for improved durability and water penetration resistance of steel windows.

  8. Superclean steel development

    SciTech Connect

    Richman, R.H.; McNaughton, W.P. )

    1989-12-01

    The Electric Power Research Institute has actively encouraged and sponsored a number of research projects to develop a superclean 3.5NiCrMoV steel for low pressure turbine rotors. Such steel is highly resistant to temper embrittlement and will thus facilitate increased efficiency in electricity generation through the use of higher operating temperatures and improvements in design. The objective of this interim report was to integrate the results that have been generated to date worldwide in the pursuit of superclean steel. The report contains detailed findings that enable the interested utility to evaluate how the results affect utility decision making. A companion document has been written to summarize the findings from this technical report. The results indicate that steels with impurity contents typical of the superclean specification can be manufactured for production rotors with properties that equal or exceed those for conventional 3.5NiCrMoV rotors in every detail. Of particular interest are the results that the superclean steels appear to be virtually resistant to temper embrittlement to a temperature of 500 {degrees}C. 109 refs., 51 figs., 9 tabs.

  9. Trends in steel technology. [Dual phase and HSLA steels

    SciTech Connect

    Not Available

    1980-01-01

    Dual phase steels, composite products, and microalloyed steels are making inroads in the automotive industry applications for bumpers, automotive parts, bodies, mechanical parts, suspension and steering equipment and truck bumpers. New steels are also used to support solar mirrors and cells, in corrosive environments in the oil and gas industry, fusion reactors, and pressure vessels in nuclear power plants. (FS)

  10. Machinability of a Stainless Steel by Electrochemical Discharge Microdrilling

    SciTech Connect

    Coteata, Margareta; Pop, Nicolae; Slatineanu, Laurentiu; Schulze, Hans-Peter; Besliu, Irina

    2011-05-04

    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.

  11. Distribution of porosity and macrosegregation in slab steel ingot

    NASA Astrophysics Data System (ADS)

    Tkadleckova, M.; Jonsta, P.; Carbol, Z.; Susovsky, M.; Michalek, K.; Socha, L.; Sviželová, J.; Zwyrtek, J.

    2017-02-01

    The paper presents a new knowledge and experiences with verification and optimization of production technology of heavy slab ingot weighing 40 t from tool steel using the results of numerical modelling and of operational experiments at a steel plant in the company VÍTKOVICE HEAVY MACHINERY a.s. The final porosity, macrosegregation and the risk of cracks were predicted. Based on the results, the slab ingot can be used instead of the conventional heavy steel ingot. Also, the ratio, the chamfer, and the external shape of the wall of the new design of the slab ingot was improved, which enabled to reduce production costs while the internal quality of steel ingots was still maintained at very high level.

  12. Continuous steel production and apparatus

    DOEpatents

    Peaslee, Kent D.; Peter, Jorg J.; Robertson, David G. C.; Thomas, Brian G.; Zhang, Lifeng

    2009-11-17

    A process for continuous refining of steel via multiple distinct reaction vessels for melting, oxidation, reduction, and refining for delivery of steel continuously to, for example, a tundish of a continuous caster system, and associated apparatus.

  13. 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.

  14. Stainless steel tanks

    SciTech Connect

    Hagen, T.

    1995-12-31

    There is currently no recognized code or standard for the design, fabrication and construction of atmospheric and low pressure stainless steel tanks. At the present time these tanks are being designed to individual specifications, manufacturers standards or utilizing other codes and standards that may not be entirely applicable. Recognizing the need, the American Petroleum Institute will be publishing a new appendix to the API STD 650 Standard which will cover stainless steel tanks. The new Appendix was put together by a Task Group of selected individuals from the API Subcommittee of Pressure Vessels and Tanks from the Committee on Refinery Equipment. This paper deals with the development and basis of the new appendix. The new appendix will provide a much needed standard to cover the material, design, fabrication, erection and testing requirements for vertical, cylindrical, austenitic stainless steel aboveground tanks in nonrefrigerated service.

  15. A-3 steel work completed

    NASA Technical Reports Server (NTRS)

    2009-01-01

    Stennis Space Center engineers celebrated a key milestone in construction of the A-3 Test Stand on April 9 - completion of structural steel work. Workers with Lafayette (La.) Steel Erector Inc. placed the last structural steel beam atop the stand during a noon ceremony attended by more than 100 workers and guests.

  16. A-3 steel work completed

    NASA Image and Video Library

    2009-04-09

    Stennis Space Center engineers celebrated a key milestone in construction of the A-3 Test Stand on April 9 - completion of structural steel work. Workers with Lafayette (La.) Steel Erector Inc. placed the last structural steel beam atop the stand during a noon ceremony attended by more than 100 workers and guests.

  17. A-3 steel work completed

    NASA Technical Reports Server (NTRS)

    2009-01-01

    Stennis Space Center engineers celebrated a key milestone in construction of the A-3 Test Stand on April 9 - completion of structural steel work. Workers with Lafayette (La.) Steel Erector Inc. placed the last structural steel beam atop the stand during a noon ceremony attended by more than 100 workers and guests.

  18. The Effect of Different Non-Metallic Inclusions on the Machinability of Steels.

    PubMed

    Ånmark, Niclas; Karasev, Andrey; Jönsson, Pär Göran

    2015-02-16

    Considerable research has been conducted over recent decades on the role of non‑metallic inclusions and their link to the machinability of different steels. The present work reviews the mechanisms of steel fractures during different mechanical machining operations and the behavior of various non-metallic inclusions in a cutting zone. More specifically, the effects of composition, size, number and morphology of inclusions on machinability factors (such as cutting tool wear, power consumption, etc.) are discussed and summarized. Finally, some methods for modification of non-metallic inclusions in the liquid steel are considered to obtain a desired balance between mechanical properties and machinability of various steel grades.

  19. The Effect of Different Non-Metallic Inclusions on the Machinability of Steels

    PubMed Central

    Ånmark, Niclas; Karasev, Andrey; Jönsson, Pär Göran

    2015-01-01

    Considerable research has been conducted over recent decades on the role of non-metallic inclusions and their link to the machinability of different steels. The present work reviews the mechanisms of steel fractures during different mechanical machining operations and the behavior of various non-metallic inclusions in a cutting zone. More specifically, the effects of composition, size, number and morphology of inclusions on machinability factors (such as cutting tool wear, power consumption, etc.) are discussed and summarized. Finally, some methods for modification of non-metallic inclusions in the liquid steel are considered to obtain a desired balance between mechanical properties and machinability of various steel grades. PMID:28787969

  20. Thermally Stable Nanocrystalline Steel

    NASA Astrophysics Data System (ADS)

    Hulme-Smith, Christopher Neil; Ooi, Shgh Woei; Bhadeshia, Harshad K. D. H.

    2017-10-01

    Two novel nanocrystalline steels were designed to withstand elevated temperatures without catastrophic microstructural changes. In the most successful alloy, a large quantity of nickel was added to stabilize austenite and allow a reduction in the carbon content. A 50 kg cast of the novel alloy was produced and used to verify the formation of nanocrystalline bainite. Synchrotron X-ray diffractometry using in situ heating showed that austenite was able to survive more than 1 hour at 773 K (500 °C) and subsequent cooling to ambient temperature. This is the first reported nanocrystalline steel with high-temperature capability.

  1. Clean cast steel technology. Final report

    SciTech Connect

    Bates, C.E.; Griffin, J.A.

    1998-06-01

    This report documents the results obtained from the Clean Cast Steel Technology Program financially supported by the DOE Metal Casting Competitiveness Research Program and industry. The primary objective of this program is to develop technology for delivering steel free of oxide macroinclusions to mold cavities. The overall objective is to improve the quality of cast steel by developing and demonstrating the technology for substantially reducing surface and sub-surface oxide inclusions. Two approaches are discussed here. A total of 23 castings were produced by submerge pouring along with sixty conventionally poured castings. The submerged poured castings contained, on average, 96% fewer observable surface inclusions (11.9 vs 0.4) compared to the conventionally poured cast parts. The variation in the population of surface inclusions also decreased by 88% from 5.5 to 0.7. The machinability of the casting was also improved by submerged pouring. The submerge poured castings required fewer cutting tool changes and less operator intervention during machining. Subsequent to these trials, the foundry has decided to purchase more shrouds for continued experimentation on other problem castings where submerge pouring is possible. An examination of melting and pouring practices in four foundries has been carried out. Three of the four foundries showed significant improvement in casting quality by manipulating the melting practice. These melting practice variables can be grouped into two separate categories. The first category is the pouring and filling practice. The second category concerns the concentration of oxidizable elements contained in the steel. Silicon, manganese, and aluminum concentrations were important factors in all four foundries. Clean heats can consistently be produced through improved melting practice and reducing exposure of the steel to atmospheric oxygen during pouring and filling.

  2. Microbial-Influenced Corrosion of Corten Steel Compared with Carbon Steel and Stainless Steel in Oily Wastewater by Pseudomonas aeruginosa

    NASA Astrophysics Data System (ADS)

    Mansouri, Hamidreza; Alavi, Seyed Abolhasan; Fotovat, Meysam

    2015-07-01

    The microbial corrosion behavior of three important steels (carbon steel, stainless steel, and Corten steel) was investigated in semi petroleum medium. This work was done in modified nutrient broth (2 g nutrient broth in 1 L oily wastewater) in the presence of Pseudomonas aeruginosa and mixed culture (as a biotic media) and an abiotic medium for 2 weeks. The behavior of corrosion was analyzed by spectrophotometric and electrochemical methods and at the end was confirmed by scanning electron microscopy. The results show that the degree of corrosion of Corten steel in mixed culture, unlike carbon steel and stainless steel, is less than P. aeruginosa inoculated medium because some bacteria affect Corten steel less than other steels. According to the experiments, carbon steel had less resistance than Corten steel and stainless steel. Furthermore, biofilm inhibits separated particles of those steels to spread to the medium; in other words, particles get trapped between biofilm and steel.

  3. Braze alloy spreading on steel

    NASA Technical Reports Server (NTRS)

    Siewert, T. A.; Heine, R. W.; Lagally, M. G.

    1978-01-01

    Scanning electron microscopy (SEM) and Auger electron microscopy (AEM) were employed to observe elemental surface decomposition resulting from the brazing of a copper-treated steel. Two types of steel were used for the study, stainless steel (treated with a eutectic silver-copper alloy), and low-carbon steel (treated with pure copper). Attention is given to oxygen partial pressure during the processes; a low enough pressure (8 x 10 to the -5th torr) was found to totally inhibit the spreading of the filler material at a fixed heating cycle. With both types of steel, copper treatment enhanced even spreading at a decreased temperature.

  4. Sensitization of stainless steel

    NASA Technical Reports Server (NTRS)

    Nagy, James P.

    1990-01-01

    The objective of this experiment is to determine the corrosion rates of 18-8 stainless steels that have been sensitized at various temperatures and to show the application of phase diagrams. The laboratory instructor will assign each student a temperature, ranging from 550 C to 1050 C, to which the sample will be heated. Further details of the experimental procedure are detailed.

  5. Material Flow during Friction Stir Welding of HSLA 65 Steel

    NASA Astrophysics Data System (ADS)

    Young, John; Field, David; Nelson, Tracy

    2013-07-01

    Material flow during friction stir welding of HSLA-65 steel was investigated by crystallographic texture analysis. During the welding process, the steel deforms primarily by local shear deformation in the austenite phase and then transforms upon cooling. Texture data from three weld specimens were compared to theoretical textures calculated using ideal Euler angles for shear in face centered cubic (FCC) structures transformed by the Kurdjumov-Sacks (KS) relationship. These theoretical textures show similarities to the experimental textures. Texture data from the weld specimens revealed a rotation of the shear direction corresponding to the tangent of the weld tool on both the area directly under the weld tool shoulder and weld cross sections. In addition, texture data showed that while the shear plane of the area under the weld tool shoulder remained constant, the shear plane of the weld cross sections is influenced by the weld tool pin.

  6. Feasibility of Underwater Friction Stir Welding of HY-80 Steel

    DTIC Science & Technology

    2011-03-01

    control procedures. A single tool of polycrystalline cubic boron nitride (PCBN) in a Tungsten- Rhenium binder was used to conduct three bead-on-plate FSW...Tungsten- Rhenium binder was used to conduct three bead-on-plate FSW traverses, approximately 40 inches in length on 0.25 inch HY-80 steel. The

  7. Fracture behavior of bainitic chromium-tungsten and chromium-molybdenum steels

    SciTech Connect

    Klueh, R.L.; Alexander, D.J.; Maziasz, P.J.

    1994-12-31

    Bainitic microstructures formed during continuous cooling of low-carbon alloy steels often appear different from classical upper and lower bainite developed by isothermal transformation. The kind of non-classical bainite produced during transformation determines the fracture behavior in a Charpy impact test. Quenching and normalizing treatments of a 3Cr-1.5Mo-0.25V-0.lC steel gave two different bainitic microstructures: a carbide-free acicular structure formed during quenching and a granular bainite formed during normalizing. The superior impact toughness of the quenched steel over the normalized steel was attributed to the difference in microstructure. A similar observation on microstructure was made for a 2.25Cr-2W-0.1C and a 2.25Cr-2W-0.25V-0.lC steel. These observations were used to develop new Cr-W steels with improved strength and impact toughness.

  8. Microstructure and Mechanical Properties of Dissimilar Friction Stir Spot Welding Between St37 Steel and 304 Stainless Steel

    NASA Astrophysics Data System (ADS)

    Khodadadi, Ali; Shamanian, Morteza; Karimzadeh, Fathallah

    2017-05-01

    In the present study, St37 low-carbon steel and 304 stainless steel were welded successfully, with the thickness of 2 mm, by a friction stir spot welding process carried out at the tool dwell time of 6 s and two different tool rotational speeds of 630 and 1250 rpm. Metallographic examinations revealed four different zones including SZ and HAZ areas of St37 steel and SZ and TMAZ regions of 304 stainless steel in the weld nugget, except the base metals. X-ray diffraction and energy-dispersive x-ray spectroscopy experiments were used to investigate the possible formation of such phases as chromium carbide. Based on these experiments, no chromium carbide precipitation was found. The recrystallization of the weld nugget in the 304 steel and the phase transformations of the weld regions in the St37 steel enhanced the hardness of the weld joint. Hardness changes of joint were acceptable and approximately uniform, as compared to the resistance spot weld. In this research, it was also observed that the tensile/shear strength, as a crucial factor, was increased with the rise in the tool rotational speed. The bond length along the interface between metals, as an effective parameter to increase the tensile/shear strength, was also determined. At higher tool rotational speeds, the bond length was found to be improved, resulting in the tensile/shear strength of 6682 N. Finally, two fracture modes were specified through the fracture mode analysis of samples obtained from the tensile/shear test consisting of the shear fracture mode and the mixed shear/tensile fracture mode.

  9. Novel 3D ultrasound image-based biomarkers based on a feature selection from a 2D standardized vessel wall thickness map: a tool for sensitive assessment of therapies for carotid atherosclerosis

    NASA Astrophysics Data System (ADS)

    Chiu, Bernard; Li, Bing; Chow, Tommy W. S.

    2013-09-01

    With the advent of new therapies and management strategies for carotid atherosclerosis, there is a parallel need for measurement tools or biomarkers to evaluate the efficacy of these new strategies. 3D ultrasound has been shown to provide reproducible measurements of plaque area/volume and vessel wall volume. However, since carotid atherosclerosis is a focal disease that predominantly occurs at bifurcations, biomarkers based on local plaque change may be more sensitive than global volumetric measurements in demonstrating efficacy of new therapies. The ultimate goal of this paper is to develop a biomarker that is based on the local distribution of vessel-wall-plus-plaque thickness change (VWT-Change) that has occurred during the course of a clinical study. To allow comparison between different treatment groups, the VWT-Change distribution of each subject must first be mapped to a standardized domain. In this study, we developed a technique to map the 3D VWT-Change distribution to a 2D standardized template. We then applied a feature selection technique to identify regions on the 2D standardized map on which subjects in different treatment groups exhibit greater difference in VWT-Change. The proposed algorithm was applied to analyse the VWT-Change of 20 subjects in a placebo-controlled study of the effect of atorvastatin (Lipitor). The average VWT-Change for each subject was computed (i) over all points in the 2D map and (ii) over feature points only. For the average computed over all points, 97 subjects per group would be required to detect an effect size of 25% that of atorvastatin in a six-month study. The sample size is reduced to 25 subjects if the average were computed over feature points only. The introduction of this sensitive quantification technique for carotid atherosclerosis progression/regression would allow many proof-of-principle studies to be performed before a more costly and longer study involving a larger population is held to confirm the treatment

  10. 77 FR 30589 - SteelRiver Infrastructure Partners LP, SteelRiver Infrastructure Associates LLC, SteelRiver...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-23

    ... Surface Transportation Board SteelRiver Infrastructure Partners LP, SteelRiver Infrastructure Associates LLC, SteelRiver Infrastructure Fund North America LP, and Patriot Funding LLC--Control Exemption--Patriot Rail Corp., et al. SteelRiver Infrastructure Partners LP (SRIP LP), SteelRiver...

  11. Evaluation of the tool life and fracture toughness of cutting tools boronized by the paste boriding process

    NASA Astrophysics Data System (ADS)

    Campos, I.; Farah, M.; López, N.; Bermúdez, G.; Rodríguez, G.; VillaVelázquez, C.

    2008-03-01

    The present study evaluates the tool life and the fracture toughness of AISI M2 steel cutting tools boronized by the paste boriding process. The treatment was done in selective form on the tool tips of the steels. The temperatures were set at 1173 and 1273 K with 4 h of exposure time and modifying the boron carbide paste thicknesses in 3 and 4 mm. Microindentation fracture toughness method was used on the borided tool at the temperature of 1273 K and a 4 mm paste thickness, with a 100 g load at different distances from the surface. Also, the borided cutting tools were worn by the turning process that implied the machining of AISI 1018 steel increasing the nominal cutting speed, of 55 m/min, in 10 and 25% and maintaining the feed and the depth cut constants. The tool life was evaluated by the Taylor's equation that shows the dependence of the experimental parameters of the boriding process.

  12. Ferritic steel melt and FLiBe/steel experiment : melting ferritic steel.

    SciTech Connect

    Troncosa, Kenneth P.; Smith, Brandon M.; Tanaka, Tina Joan

    2004-11-01

    In preparation for developing a Z-pinch IFE power plant, the interaction of ferritic steel with the coolant, FLiBe, must be explored. Sandia National Laboratories Fusion Technology Department was asked to drop molten ferritic steel and FLiBe in a vacuum system and determine the gas byproducts and ability to recycle the steel. We tried various methods of resistive heating of ferritic steel using available power supplies and easily obtained heaters. Although we could melt the steel, we could not cause a drop to fall. This report describes the various experiments that were performed and includes some suggestions and materials needed to be successful. Although the steel was easily melted, it was not possible to drip the molten steel into a FLiBe pool Levitation melting of the drop is likely to be more successful.

  13. Laser Welded Corrugated Steel Panels in Industrial Applications

    NASA Astrophysics Data System (ADS)

    Kananen, M.; Mäntyjärvi, K.; Keskitalo, M.; Hietala, M.; Järvenpää, A.; Holappa, K.; Saine, K.; Teiskonen, J.

    Corrugated core steel panels are an effective way to reduce weight and increase stiffness of steel structures. In numerous applications, these panels have shown very promising commercial possibilities. This study presents the design, manufacturing and commercializing process for two practical examples: Case 1) a fly wheel cover for a diesel engine and Case 2) rotationally symmetrical panel for an electric motor. Test materials of various kinds were used for corrugated cores and skin plates: conventional low-carbon steel grade EN 10130 and ferritic stainless steel grade 1.4509 with plate the thicknesses of 0.5, 0.6 and 0.75 mm. To manufacture different kinds of corrugated core steel panels, flexible manufacturing tools and cost-effective processes are needed. The most important criterion for laser welding panels was the capability of forming tools for producing high quality geometry for the core. Laser welding assembly showed that the quality of the core in both studied cases was good enough for welding the lap joints properly. Developed panels have been tested in industrial applications with excellent feedback. If thickness of a corrugated panel structure is not a limiting issue, these panels are good solution on application where stiffness and lighter weight are required as well as vibrational aspect considered.

  14. History of ultrahigh carbon steels

    SciTech Connect

    Wadsworth, J.; Sherby, O.D.

    1997-06-20

    The history and development of ultrahigh carbon steels (i.e., steels containing between 1 and 2.l percent C and now known as UHCS) are described. The early use of steel compositions containing carbon contents above the eutectoid level is found in ancient weapons from around the world. For example, both Damascus and Japanese sword steels are hypereutectoid steels. Their manufacture and processing is of interest in understanding the role of carbon content in the development of modern steels. Although sporadic examples of UHCS compositions are found in steels examined in the early part of this century, it was not until the mid-1970s that the modern study began. This study had its origin in the development of superplastic behavior in steels and the recognition that increasing the carbon content was of importance in developing that property. The compositions that were optimal for superplasticity involved the development of steels that contained higher carbon contents than conventional modern steels. It was discovered, however, that the room temperature properties of these compositions were of interest in their own right. Following this discovery, a period of intense work began on understanding their manufacture, processing, and properties for both superplastic forming and room temperature applications. The development of superplastic cast irons and iron carbides, as well as those of laminated composites containing UHCS, was an important part of this history.

  15. Galvanised steel to aluminium joining by laser and GTAW processes

    SciTech Connect

    Sierra, G.; Peyre, P.; Deschaux Beaume, F. Stuart, D.; Fras, G.

    2008-12-15

    A new means of assembling galvanised steel to aluminium involving a reaction between solid steel and liquid aluminium was developed, using laser and gas tungsten arc welding (GTAW) processes. A direct aluminium melting strategy was investigated with the laser process, whereas an aluminium-induced melting by steel heating and heat conduction through the steel was carried out with the GTAW process. The interfaces generated during the interaction were mainly composed of a 2-40 {mu}m thick intermetallic reaction layers. The linear strength of the assemblies can be as high as 250 N/mm and 190 N/mm for the assemblies produced respectively by laser and GTAW processes. The corresponding failures were located in the fusion zone of aluminium (laser assemblies), or in the reaction layer (GTAW assemblies)

  16. Jetting tool

    SciTech Connect

    Szarka, D.D.; Schwegman, S.L.

    1991-07-09

    This patent describes an apparatus for hydraulically jetting a well tool disposed in a well, the well tool having a sliding member. It comprises positioner means for operably engaging the sliding member of the well tool; and a jetting means, connected at a rotatable connection to the positioner means so that the jetting means is rotatable relative to the positioner means and the well tool, for hydraulically jetting the well tool as the jetting means is rotated relative thereto.

  17. Mechanism study on the wear of polycrystalline cubic boron nitride cutting tools

    NASA Astrophysics Data System (ADS)

    Jia, Yunhai; Li, Jiangang

    2010-12-01

    The samples of bearing steel, alloy cold-die steel, cold-harden cast iron were continuous machined by polycrystalline cubic boron nitride(PcBN) cutting tools dry turning. After the machining, the phases of cutting tools blade-edge were analyzed by X-ray diffraction analyzer and cutting tools blade-edge microstructure were observed by scanning electronic microscope. And then, the wear mechanism of PcBN cutting tools in turing process was studied. The result showed that the oxidation wear and felt wear were main invalidation factors using PcBN cutting tools dry turning bearing steel and alloy cold-die steel samples; chemical wear and oxidation wear were main invalidation factors using PcBN cutting tools dry turning cold-harden cast iron. In turning process, the granularity of cBN, the heated-stability and chemical characteristic of felt material have key function to cutting tools wear.

  18. 46 CFR 59.20-1 - Carbon-steel or alloy-steel castings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Carbon-steel or alloy-steel castings. 59.20-1 Section 59... BOILERS, PRESSURE VESSELS AND APPURTENANCES Welding Repairs to Castings § 59.20-1 Carbon-steel or alloy-steel castings. Defects in carbon-steel or alloy-steel castings may be repaired by welding. The...

  19. 46 CFR 59.20-1 - Carbon-steel or alloy-steel castings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Carbon-steel or alloy-steel castings. 59.20-1 Section 59... BOILERS, PRESSURE VESSELS AND APPURTENANCES Welding Repairs to Castings § 59.20-1 Carbon-steel or alloy-steel castings. Defects in carbon-steel or alloy-steel castings may be repaired by welding. The...

  20. 46 CFR 59.20-1 - Carbon-steel or alloy-steel castings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Carbon-steel or alloy-steel castings. 59.20-1 Section 59... BOILERS, PRESSURE VESSELS AND APPURTENANCES Welding Repairs to Castings § 59.20-1 Carbon-steel or alloy-steel castings. Defects in carbon-steel or alloy-steel castings may be repaired by welding. The...

  1. 46 CFR 59.20-1 - Carbon-steel or alloy-steel castings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Carbon-steel or alloy-steel castings. 59.20-1 Section 59... BOILERS, PRESSURE VESSELS AND APPURTENANCES Welding Repairs to Castings § 59.20-1 Carbon-steel or alloy-steel castings. Defects in carbon-steel or alloy-steel castings may be repaired by welding. The...

  2. 46 CFR 59.20-1 - Carbon-steel or alloy-steel castings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Carbon-steel or alloy-steel castings. 59.20-1 Section 59... BOILERS, PRESSURE VESSELS AND APPURTENANCES Welding Repairs to Castings § 59.20-1 Carbon-steel or alloy-steel castings. Defects in carbon-steel or alloy-steel castings may be repaired by welding. The...

  3. Coated 4340 Steel

    DTIC Science & Technology

    2013-08-26

    plasma vapor NAWCADPAX/TR-2013/252 2 deposition (reference 9), chemical vapor deposition, hot dip galvanizing, anodizing, composite coatings ...electroplating on 4340 steel. Assess the impact of substitute primer and sacrificial coating on corrosion fatigue and SCC, in particular leading ...alternative coatings qualified to MIL-PRE-23377 Class N and an electroplated zinc -nickel alloy passivated with a trivalent chromium solution which is

  4. Ultrahigh Carbon Steel.

    DTIC Science & Technology

    1984-10-01

    ferrite grains, 0.5-2 pm, containing fine spheroidized cementite particles, they have been shown not only to be super - plastic at intermediate...utilized to prepare ferrous laminated composites with super - plastic properties at intermediate temperatures’ 19 Ŗ 1 and with very high impact resistance...as an alloying addition that could alter the super - plastic properties of UHC steels because of its influence on the thermodynam- ics of the Fe-C

  5. Nanoprecipitates in Steels

    SciTech Connect

    Schneibel, Joachim H; Lu, Zhao Ping; Shim, Sang Hoon

    2007-01-01

    The creep strength of ferritic steels can be substantially improved by the incorporation of a high number density of nano-scale dispersoids. Examples for such alloys are the oxide dispersion strengthened steels MA956, MA957, and PM2000. The dispersoids in these steels contain Y and Ti, or Y and Al. They can be as small as a few nanometers in size. Processing is traditionally carried out by mechanical alloying of elemental or pre-alloyed powders mixed with Y{sub 2}O{sub 3} powder. The goal of the present research is to identify alternative ways of producing ultrafine dispersoids. One possible way is internal oxidation, in which reactive elements dissolved in a metallic matrix are selectively oxidized. Internal oxidation experiments were carried out with Fe-Y, Fe-Ti-Y, and Fe-Al-Y precursors. Microstructural analysis showed that dispersoid dimensions as small as 10 nm could be achieved. Atomized Fe-0.25 at% Y powder was internally oxidized and consolidated by hot forging. An increase in the high-temperature creep strength by {approx} 20% was observed. Since it is likely that the composition of the precursor alloys is crucial for maximizing the number density and thermal stability of the oxides, experiments allowing the rapid screening of different compositions have been initiated.

  6. Nanoprecipitates in Steels

    SciTech Connect

    Schneibel, Joachim H; Kad, Bimal

    2008-01-01

    The creep strength of ferritic steels can be substantially improved by the incorporation of a high number density of nano-scale dispersoids. Examples for such alloys are the oxide dispersion strengthened steels MA956, MA957, and PM2000. The dispersoids in these steels contain Y and Ti, or Y and Al. They can be as small as a few nanometers in size. Processing is traditionally carried out by mechanical alloying of elemental or pre-alloyed powders mixed with Y{sub 2}O{sub 3} powder. The goal of the present research is to identify alternative ways of producing ultrafine dispersoids. One possible way is internal oxidation, in which reactive elements dissolved in a metallic matrix are selectively oxidized. Internal oxidation experiments were carried out with Fe-Y, Fe-Ti-Y, and Fe-Al-Y precursors. Microstructural analysis showed that dispersoid dimensions as small as 10 nm could be achieved. Atomized Fe-0.25 at% Y powder was internally oxidized and consolidated by hot forging. An increase in the high-temperature creep strength by {approx} 20% was observed. Since it is likely that the composition of the precursor alloys is crucial for maximizing the number density and thermal stability of the oxides, experiments allowing the rapid screening of different compositions have been initiated.

  7. Stainless Steel Permeability

    SciTech Connect

    Buchenauer, Dean A.; Karnesky, Richard A.

    2015-09-01

    An understanding of the behavior of hydrogen isotopes in materials is critical to predicting tritium transport in structural metals (at high pressure), estimating tritium losses during production (fission environment), and predicting in-vessel inventory for future fusion devices (plasma driven permeation). Current models often assume equilibrium diffusivity and solubility for a class of materials (e.g. stainless steels or aluminum alloys), neglecting trapping effects or, at best, considering a single population of trapping sites. Permeation and trapping studies of the particular castings and forgings enable greater confidence and reduced margins in the models. For FY15, we have continued our investigation of the role of ferrite in permeation for steels of interest to GTS, through measurements of the duplex steel 2507. We also initiated an investigation of the permeability in work hardened materials, to follow up on earlier observations of unusual permeability in a particular region of 304L forgings. Samples were prepared and characterized for ferrite content and coated with palladium to prevent oxidation. Issues with the poor reproducibility of measurements at low permeability were overcome, although the techniques in use are tedious. Funding through TPBAR and GTS were secured for a research grade quadrupole mass spectrometer (QMS) and replacement turbo pumps, which should improve the fidelity and throughput of measurements in FY16.

  8. Phase transformations in steels: Processing, microstructure, and performance

    SciTech Connect

    Gibbs, Paul J.

    2014-04-03

    In this study, contemporary steel research is revealing new processing avenues to tailor microstructure and properties that, until recently, were only imaginable. Much of the technological versatility facilitating this development is provided by the understanding and utilization of the complex phase transformation sequences available in ferrous alloys. Today we have the opportunity to explore the diverse phenomena displayed by steels with specialized analytical and experimental tools. Advances in multi-scale characterization techniques provide a fresh perspective into microstructural relationships at the macro- and micro-scale, enabling a fundamental understanding of the role of phase transformations during processing and subsequent deformation.

  9. Computational Strategies for Polymer Coated Steel Sheet Forming Simulations

    SciTech Connect

    Owen, D. R. J.; Andrade Pires, F. M.; Dutko, M.

    2007-05-17

    This contribution discusses current issues involved in the numerical simulation of large scale industrial forming processes that employ polymer coated steel sheet. The need for rigorous consideration of both theoretical and algorithmic issues is emphasized, particularly in relation to the computational treatment of finite strain deformation of polymer coated steel sheet in the presence of internal degradation. Other issues relevant to the effective treatment of the problem, including the modelling of frictional contact between the work piece and tools, low order element technology capable of dealing with plastic incompressibility and thermo mechanical coupling, are also addressed. The suitability of the overall approach is illustrated by the solution of an industrially relevant problem.

  10. Computational Strategies for Polymer Coated Steel Sheet Forming Simulations

    NASA Astrophysics Data System (ADS)

    Owen, D. R. J.; Andrade Pires, F. M.; Dutko, M.

    2007-05-01

    This contribution discusses current issues involved in the numerical simulation of large scale industrial forming processes that employ polymer coated steel sheet. The need for rigorous consideration of both theoretical and algorithmic issues is emphasized, particularly in relation to the computational treatment of finite strain deformation of polymer coated steel sheet in the presence of internal degradation. Other issues relevant to the effective treatment of the problem, including the modelling of frictional contact between the work piece and tools, low order element technology capable of dealing with plastic incompressibility and thermo mechanical coupling, are also addressed. The suitability of the overall approach is illustrated by the solution of an industrially relevant problem.

  11. Process for dezincing galvanized steel

    DOEpatents

    Morgan, W.A.; Dudek, F.J.; Daniels, E.J.

    1998-07-14

    A process is described for removing zinc from galvanized steel. The galvanized steel is immersed in an electrolyte containing at least about 15% by weight of sodium or potassium hydroxide and having a temperature of at least about 75 C and the zinc is galvanically corroded from the surface of the galvanized steel. The material serving as the cathode is principally a material having a standard electrode potential which is intermediate of the standard electrode potentials of zinc and cadmium in the electrochemical series. The corrosion rate may be accelerated by (1) increasing the number density of corrosion sites in the galvanized steel by mechanically abrading or deforming the galvanized steel, (2) heating the galvanized steel to form an alloy of zinc on the surface of the galvanized steel, (3) mixing the galvanized steel with a material having a standard electrode potential which is intermediate of the standard electrode potentials of zinc and cadmium in the electrochemical series, or (4) moving the galvanized steel relative to itself and to the electrolyte while immersed in the electrolyte. 1 fig.

  12. Process for dezincing galvanized steel

    DOEpatents

    Morgan, William A.; Dudek, Frederick J.; Daniels, Edward J.

    1998-01-01

    A process for removing zinc from galvanized steel. The galvanized steel is immersed in an electrolyte containing at least about 15% by weight of sodium or potassium hydroxide and having a temperature of at least about 75.degree. C. and the zinc is galvanically corroded from the surface of the galvanized steel. The material serving as the cathode is principally a material having a standard electrode potential which is intermediate of the standard electrode potentials of zinc and cadmium in the electrochemical series. The corrosion rate may be accelerated by (i) increasing the number density of corrosion sites in the galvanized steel by mechanically abrading or deforming the galvanized steel, (ii) heating the galvanized steel to form an alloy of zinc on the surface of the galvanized steel, (iii) mixing the galvanized steel with a material having a standard electrode potential which is intermediate of the standard electrode potentials of zinc and cadmium in the electrochemical series, or (iv) moving the galvanized steel relative to itself and to the electrolyte while immersed in the electrolyte.

  13. Hydrogen Embrittlement of Gun Steel

    DTIC Science & Technology

    1987-11-01

    8217s HY80 and HY130 steels were checked for the critical hydrogen concentrations which were determined to be 6 ppm for HY8O steel 8 and 3 ppm for HY130...JOTC FILE COPY AD-A188 972 AD 1 TECHNICAL REPORT ARCCB-TR-87030 HYDROGEN EMBRITTLEMENT OF GUN STEEL F’ GERALD L. SPFNCER DTIC DEC 1 5 1987 NOVEMBER...PtEtIOC COVERED HYDROGEN EMBRITTLEHENT OF GUN STEEL Final OG EOTNME 6. PERFORMINGORO EOTNME 7. A*JTNOR(s) S. CONTRACT OR GRANT NUMBER(&) Gerald L

  14. High strength, tough alloy steel

    DOEpatents

    Thomas, Gareth; Rao, Bangaru V. N.

    1979-01-01

    A high strength, tough alloy steel is formed by heating the steel to a temperature in the austenite range (1000.degree.-1100.degree. C.) to form a homogeneous austenite phase and then cooling the steel to form a microstructure of uniformly dispersed dislocated martensite separated by continuous thin boundary films of stabilized retained austenite. The steel includes 0.2-0.35 weight % carbon, at least 1% and preferably 3-4.5% chromium, and at least one other substitutional alloying element, preferably manganese or nickel. The austenite film is stable to subsequent heat treatment as by tempering (below 300.degree. C.) and reforms to a stable film after austenite grain refinement.

  15. Induction heat treatment of steel

    SciTech Connect

    Semiatin, S.L.; Stutz, D.E.

    1985-01-01

    This book discusses the induction heating. After reviewing heat treating operations for steel and the principles of the heat treatment of steel, an overview of induction heat treating is provided. Next, consideration is given to equipment and equipment selection, coil design, power requirements and temperature control. A discussion of surface and through hardening of steel is provided, including information on frequency and power selection and quenching apparatus. Tempering is considered, followed by information on control of residual stresses, cracking, temper brittleness and the important metallurgical and hardness differences between induction and furnace treated steel.

  16. Tool Wear in Friction Drilling

    SciTech Connect

    Miller, Scott F; Blau, Peter Julian; Shih, Albert J.

    2007-01-01

    This study investigated the wear of carbide tools used in friction drilling, a nontraditional hole-making process. In friction drilling, a rotating conical tool uses the heat generated by friction to soften and penetrate a thin workpiece and create a bushing without generating chips. The wear of a hard tungsten carbide tool used for friction drilling a low carbon steel workpiece has been investigated. Tool wear characteristics were studied by measuring its weight change, detecting changes in its shape with a coordinate measuring machine, and making observations of wear damage using scanning electron microscopy. Energy dispersive spectroscopy was applied to analyze the change in chemical composition of the tool surface due to drilling. In addition, the thrust force and torque during drilling and the hole size were measured periodically to monitor the effects of tool wear. Results indicate that the carbide tool is durable, showing minimal tool wear after drilling 11000 holes, but observations also indicate progressively severe abrasive grooving on the tool tip.

  17. New downhole tool designed for well servicing

    SciTech Connect

    Schempf, F.J.

    1982-02-01

    Miracle Tool, Inc. is finding quite a large market for its single product line - the miracle tool. Basically, the tool is designed to perform numerous downhole operations in shallow or deep completion and workover drilling. Unlike most other tools used for cleaning out cased or open holes, the miracle tool operates in a low fluid level environment. The tool uses a method for circulating fluid downhole, without the added expense of loading the hole with pumped-down fluid. The all-stainless steel tool is designed to remove frac and, retrieve bridge plugs, drill out caved-in holes, drill out cement and hydromite plugs, and fish for small junk, including drill bit cones. The application of the miracle tool to drilling and fishing are discussed.

  18. Tool Carrier

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Tool organizer accommodates a selection of hand tools on a waist or thigh belt or alternately on wall, work bench, or car trunk mountings. Tool caddy is widely used by industrial maintenance personnel, TV technicians, mechanics, artists, draftsmen, hobbyists and homeowners. Its innovative feature is rows of flexible vinyl "fingers" like the bristles of a hairbrush which mesh together to hold the tool securely in place yet allow easy insertion or withdrawal. Product is no longer commercially available.

  19. Percussion tool

    DOEpatents

    Reed, Teddy R.

    2006-11-28

    A percussion tool is described and which includes a housing mounting a tool bit; a reciprocally moveable hammer borne by the housing and which is operable to repeatedly strike the tool bit; and a reciprocally moveable piston enclosed within the hammer and which imparts reciprocal movement to the reciprocally moveable hammer.

  20. FORTRAN tools

    NASA Technical Reports Server (NTRS)

    Presser, L.

    1978-01-01

    An integrated set of FORTRAN tools that are commercially available is described. The basic purpose of various tools is summarized and their economic impact highlighted. The areas addressed by these tools include: code auditing, error detection, program portability, program instrumentation, documentation, clerical aids, and quality assurance.

  1. Reliability-based condition assessment of steel containment and liners

    SciTech Connect

    Ellingwood, B.; Bhattacharya, B.; Zheng, R.

    1996-11-01

    Steel containments and liners in nuclear power plants may be exposed to aggressive environments that may cause their strength and stiffness to decrease during the plant service life. Among the factors recognized as having the potential to cause structural deterioration are uniform, pitting or crevice corrosion; fatigue, including crack initiation and propagation to fracture; elevated temperature; and irradiation. The evaluation of steel containments and liners for continued service must provide assurance that they are able to withstand future extreme loads during the service period with a level of reliability that is sufficient for public safety. Rational methodologies to provide such assurances can be developed using modern structural reliability analysis principles that take uncertainties in loading, strength, and degradation resulting from environmental factors into account. The research described in this report is in support of the Steel Containments and Liners Program being conducted for the US Nuclear Regulatory Commission by the Oak Ridge National Laboratory. The research demonstrates the feasibility of using reliability analysis as a tool for performing condition assessments and service life predictions of steel containments and liners. Mathematical models that describe time-dependent changes in steel due to aggressive environmental factors are identified, and statistical data supporting the use of these models in time-dependent reliability analysis are summarized. The analysis of steel containment fragility is described, and simple illustrations of the impact on reliability of structural degradation are provided. The role of nondestructive evaluation in time-dependent reliability analysis, both in terms of defect detection and sizing, is examined. A Markov model provides a tool for accounting for time-dependent changes in damage condition of a structural component or system. 151 refs.

  2. The industrial ecology of steel

    SciTech Connect

    Considine, Timothy J.; Jablonowski, Christopher; Considine, Donita M.M.; Rao, Prasad G.

    2001-03-26

    This study performs an integrated assessment of new technology adoption in the steel industry. New coke, iron, and steel production technologies are discussed, and their economic and environmental characteristics are compared. Based upon detailed plant level data on cost and physical input-output relations by process, this study develops a simple mathematical optimization model of steel process choice. This model is then expanded to a life cycle context, accounting for environmental emissions generated during the production and transportation of energy and material inputs into steelmaking. This life-cycle optimization model provides a basis for evaluating the environmental impacts of existing and new iron and steel technologies. Five different plant configurations are examined, from conventional integrated steel production to completely scrap-based operations. Two cost criteria are used to evaluate technology choice: private and social cost, with the latter including the environmental damages associated with emissions. While scrap-based technologies clearly generate lower emissions in mass terms, their emissions of sulfur dioxide and nitrogen oxides are significantly higher. Using conventional damage cost estimates reported in the literature suggests that the social costs associated with scrap-based steel production are slightly higher than with integrated steel production. This suggests that adopting a life-cycle viewpoint can substantially affect environmental assessment of new technologies. Finally, this study also examines the impacts of carbon taxes on steel production costs and technology choice.

  3. MINOS Detector Steel Magnetic Measurements

    SciTech Connect

    Robert C. Trendler and Walter F. Jaskierny

    1999-03-03

    Magnetic measurements were made on one steel plate of the MINOS far detector. The conventionally used technique of measuring sense coil voltage induced by step changes in excitation current voltage was successful in providing stable, repeatable measurements. Measurements were made at several locations on the steel and the results are presented.

  4. Hydrogen Embrittlement of Structural Steels

    SciTech Connect

    Somerday, Brian P.; San Marchi, Christopher W

    2014-08-01

    Carbon-manganese steels are candidates for the structural materials in hydrogen gas pipelines; however, it is well known that these steels are susceptible to hydrogen embrittlement. Decades of research and industrial experience have established that hydrogen embrittlement compromises the structural integrity of steel components. This experience has also helped identify the failure modes that can operate in hydrogen containment structures. As a result, there are tangible ideas for managing hydrogen embrittlement in steels and quantifying safety margins for steel hydrogen containment structures. For example, fatigue crack growth aided by hydrogen embrittlement is a well-established failure mode for steel hydrogen containment structures subjected to pressure cycling. This pressure cycling represents one of the key differences in operating conditions between current hydrogen pipelines and those anticipated in a hydrogen delivery infrastructure. Applying structural integrity models in design codes coupled with measurement of relevant material properties allows quantification of the reliability/integrity of steel hydrogen pipelines subjected to pressure cycling. Furthermore, application of these structural integrity models is aided by the development of physics-based predictive models, which provide important insights such as the effects of microstructure on hydrogen-assisted fatigue crack growth. Successful implementation of these structural integrity and physics-based models enhances confidence in the design codes and enables decisions about materials selection and operating conditions for reliable and efficient steel hydrogen pipelines.

  5. Correlating tool wear, tool life, surface roughness and tool vibration in finish turning with coated carbide tools

    NASA Astrophysics Data System (ADS)

    Bonifacio, M. E. R.; Diniz, A. E.

    1994-04-01

    Experiments have been carried out in an attempt to monitor the change of workpiece surface roughness caused by the increase of tool wear, through the variation of the vibration in finish turning, under different cutting conditions. The vibration was measured by two accelerometers attached to the tool and the parameter used to make the correlation with surface roughness was the r.m.s. of the signal. The tool of one experiment was photographed at different stages of the cut in order to explain the wear formation and the behaviour of surface roughness as the cutting time elapsed. The material machined was AISI 4340 steel and the tool was coated carbide inserts. The results show that vibration of the tool can be a good way to monitor on-line the growth of surface roughness in finish turning and, therefore, it can be useful for establishing the end of tool life in these operations. Another conclusion is that, when coated tools are used, the behaviour of surface roughness as cutting time elapses is very different from that when uncoated tools are used.

  6. AISI/DOE Technology Roadmap Program: Characterization of Fatigue and Crash Performance of New Generation High Strength Steels for Automotive Applications

    SciTech Connect

    Brenda Yan; Dennis Urban

    2003-04-21

    A 2-year project (2001-2002) to generate fatigue and high strain data for a new generation of high strength steels (HSS) has been completed in December 2002. The project tested eleven steel grades, including Dual Phase (DP) steels, Transformation-Induced Plasticity (TRIP) steels, Bake Hardenable (BH) steels, and conventional High Strength Low Alloy (HSLA) steels. All of these steels are of great interest in automotive industry due to the potential benefit in weight reduction, improved fuel economy, enhanced crash energy management and total system cost savings. Fatigue behavior includes strain controlled fatigue data notch sensitivity for high strength steels. High strain rate behavior includes stress-strain data for strain rates from 0.001/s to 1000/s, which are considered the important strain rate ranges for crash event. The steels were tested in two phases, seven were tested in Phase 1 and the remaining steels were tested in Phase. In a addition to the fatigue data and high st rain rate data generated for the steels studied in the project, analyses of the testing results revealed that Advanced High Strength Steels (AHSS) exhibit significantly higher fatigue strength and crash energy absorption capability than conventional HSS. TRIP steels exhibit exceptionally better fatigue strength than steels of similar tensile strength but different microstructure, for conditions both with or without notches present

  7. Magnetoacoustic stress measurements in steel

    NASA Technical Reports Server (NTRS)

    Namkung, M.; Utrata, D.; Allison, S. G.; Heyman, J. S.

    1985-01-01

    Uniaxial stress effects on the low-field magnetoacoustic interaction have been studied using bulk compressional waves and Rayleigh surface waves in numerous steel samples having various impurity concentrations (Namkung et al., 1984). The results invariably showed that the initial slope of acoustic natural velocity variations, with respect to net induced magnetization parallel to the stress axis, is positive under tension and negative under compression. The results of current measurements in railroad rail steel having about 0.68 wt percent carbon content are typical for medium range carbon steels. The low-field natural velocity slope in this particular type of steel, which is almost zero when unstressed, becomes steeper with increased magnitude of stress in both directions. Hence, the nondestructive determination of the sign of residual stress in railroad wheels and rails is possible using this technique. This paper discusses the basic physical mechanism underlying the experimental observations and presents the results obtained in railroad rail steel.

  8. Advanced cryogenics for cutting tools. Final report

    SciTech Connect

    Lazarus, L.J.

    1996-10-01

    The purpose of the investigation was to determine if cryogenic treatment improved the life and cost effectiveness of perishable cutting tools over other treatments or coatings. Test results showed that in five of seven of the perishable cutting tools tested there was no improvement in tool life. The other two tools showed a small gain in tool life, but not as much as when switching manufacturers of the cutting tool. The following conclusions were drawn from this study: (1) titanium nitride coatings are more effective than cryogenic treatment in increasing the life of perishable cutting tools made from all cutting tool materials, (2) cryogenic treatment may increase tool life if the cutting tool is improperly heat treated during its origination, and (3) cryogenic treatment was only effective on those tools made from less sophisticated high speed tool steels. As a part of a recent detailed investigation, four cutting tool manufacturers and two cutting tool laboratories were queried and none could supply any data to substantiate cryogenic treatment of perishable cutting tools.

  9. Computational algorithms to simulate the steel continuous casting

    NASA Astrophysics Data System (ADS)

    Ramírez-López, A.; Soto-Cortés, G.; Palomar-Pardavé, M.; Romero-Romo, M. A.; Aguilar-López, R.

    2010-10-01

    Computational simulation is a very powerful tool to analyze industrial processes to reduce operating risks and improve profits from equipment. The present work describes the development of some computational algorithms based on the numerical method to create a simulator for the continuous casting process, which is the most popular method to produce steel products for metallurgical industries. The kinematics of industrial processing was computationally reproduced using subroutines logically programmed. The cast steel by each strand was calculated using an iterative method nested in the main loop. The process was repeated at each time step (Δ t) to calculate the casting time, simultaneously, the steel billets produced were counted and stored. The subroutines were used for creating a computational representation of a continuous casting plant (CCP) and displaying the simulation of the steel displacement through the CCP. These algorithms have been developed to create a simulator using the programming language C++. Algorithms for computer animation of the continuous casting process were created using a graphical user interface (GUI). Finally, the simulator functionality was shown and validated by comparing with the industrial information of the steel production of three casters.

  10. Active Site Mutations as a Suitable Tool Contributing to Explain a Mechanism of Aristolochic Acid I Nitroreduction by Cytochromes P450 1A1, 1A2 and 1B1

    PubMed Central

    Milichovský, Jan; Bárta, František; Schmeiser, Heinz H.; Arlt, Volker M.; Frei, Eva; Stiborová, Marie; Martínek, Václav

    2016-01-01

    Aristolochic acid I (AAI) is a plant drug found in Aristolochia species that causes aristolochic acid nephropathy, Balkan endemic nephropathy and their associated urothelial malignancies. AAI is activated via nitroreduction producing genotoxic N-hydroxyaristolactam, which forms DNA adducts. The major enzymes responsible for the reductive bioactivation of AAI are NAD(P)H:quinone oxidoreductase and cytochromes P450 (CYP) 1A1 and 1A2. Using site-directed mutagenesis we investigated the possible mechanisms of CYP1A1/1A2/1B1-catalyzed AAI nitroreduction. Molecular modelling predicted that the hydroxyl groups of serine122/threonine124 (Ser122/Thr124) amino acids in the CYP1A1/1A2-AAI binary complexes located near to the nitro group of AAI, are mechanistically important as they provide the proton required for the stepwise reduction reaction. In contrast, the closely related CYP1B1 with no hydroxyl group containing residues in its active site is ineffective in catalyzing AAI nitroreduction. In order to construct an experimental model, mutant forms of CYP1A1 and 1A2 were prepared, where Ser122 and Thr124 were replaced by Ala (CYP1A1-S122A) and Val (CYP1A2-T124V), respectively. Similarly, a CYP1B1 mutant was prepared in which Ala133 was replaced by Ser (CYP1B1-A133S). Site-directed mutagenesis was performed using a quickchange approach. Wild and mutated forms of these enzymes were heterologously expressed in Escherichia coli and isolated enzymes characterized using UV-vis spectroscopy to verify correct protein folding. Their catalytic activity was confirmed with CYP1A1, 1A2 and 1B1 marker substrates. Using 32P-postlabelling we determined the efficiency of wild-type and mutant forms of CYP1A1, 1A2, and 1B1 reconstituted with NADPH:CYP oxidoreductase to bioactivate AAI to reactive intermediates forming covalent DNA adducts. The S122A and T124V mutations in CYP1A1 and 1A2, respectively, abolished the efficiency of CYP1A1 and 1A2 enzymes to generate AAI-DNA adducts. In contrast

  11. Active Site Mutations as a Suitable Tool Contributing to Explain a Mechanism of Aristolochic Acid I Nitroreduction by Cytochromes P450 1A1, 1A2 and 1B1.

    PubMed

    Milichovský, Jan; Bárta, František; Schmeiser, Heinz H; Arlt, Volker M; Frei, Eva; Stiborová, Marie; Martínek, Václav

    2016-02-05

    Aristolochic acid I (AAI) is a plant drug found in Aristolochia species that causes aristolochic acid nephropathy, Balkan endemic nephropathy and their associated urothelial malignancies. AAI is activated via nitroreduction producing genotoxic N-hydroxyaristolactam, which forms DNA adducts. The major enzymes responsible for the reductive bioactivation of AAI are quinone oxidoreductase and cytochromes P450 (CYP) 1A1 and 1A2. Using site-directed mutagenesis we investigated the possible mechanisms of CYP1A1/1A2/1B1-catalyzed AAI nitroreduction. Molecular modelling predicted that the hydroxyl groups of serine122/threonine124 (Ser122/Thr124) amino acids in the CYP1A1/1A2-AAI binary complexes located near to the nitro group of AAI, are mechanistically important as they provide the proton required for the stepwise reduction reaction. In contrast, the closely related CYP1B1 with no hydroxyl group containing residues in its active site is ineffective in catalyzing AAI nitroreduction. In order to construct an experimental model, mutant forms of CYP1A1 and 1A2 were prepared, where Ser122 and Thr124 were replaced by Ala (CYP1A1-S122A) and Val (CYP1A2-T124V), respectively. Similarly, a CYP1B1 mutant was prepared in which Ala133 was replaced by Ser (CYP1B1-A133S). Site-directed mutagenesis was performed using a quickchange approach. Wild and mutated forms of these enzymes were heterologously expressed in Escherichia coli and isolated enzymes characterized using UV-vis spectroscopy to verify correct protein folding. Their catalytic activity was confirmed with CYP1A1, 1A2 and 1B1 marker substrates. Using (32)P-postlabelling we determined the efficiency of wild-type and mutant forms of CYP1A1, 1A2, and 1B1 reconstituted with NADPH:CYP oxidoreductase to bioactivate AAI to reactive intermediates forming covalent DNA adducts. The S122A and T124V mutations in CYP1A1 and 1A2, respectively, abolished the efficiency of CYP1A1 and 1A2 enzymes to generate AAI-DNA adducts. In contrast, the

  12. 2169 Steel Waveform Experiments

    NASA Astrophysics Data System (ADS)

    Furnish, M.; Alexander, C.; Reinhart, W.; Brown, J.

    2013-06-01

    In support of efforts to develop multiscale models of materials, we performed eight gas gun impact experiments on 2169 steel (21% Cr, 6% Ni, 9% Mn). These experiments provided shock, reshock and release velocimetry data, with initial shock stresses ranging from 10 to 50 GPa (particle velocities from 0.25 to 1.05 km/s). Both windowed and free-surface measurements were used, with samples 1 to 5 mm thick. The study focused on dynamic strength determination via the release/reshock paths. Reshock tests with explosively welded impactors produced clean results. The free-surface samples, which were steps on a single piece of steel, showed lower wavespeeds for thin (1 mm) samples than for thicker (2 or 4 mm) samples. A configuration used for the last three shots allowed release information to be determined from these free surface samples as well. The sample strength appears to increase with stress from ~1 GPa to ~3 GPa over this range, consistent with other recent work but about 40% above the Steinberg model. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  13. Steel forgings: Second volume

    SciTech Connect

    Nisbett, E.G.; Melilli, A.S.

    1997-12-31

    Steel is supplied in many product forms, most of which are produced in terms of basic dimensions such as width and thickness, or diameter and with length describing quantity. Forgings and castings by contrast are diverse in shape and form and are individually made for a specific purpose, either as self contained units such as crankshafts, valve bodies or turbine rotors, or as discrete components to be fabricated into a larger assembly, as for example a nozzle for a pressure vessel. The specification and testing of forgings is therefore more varied, complex, and demanding than is the case for other product forms. This is augmented by the fact that forgings are often expected to give better reliability and service performance than can be expected when the same part is fabricated from sections of other steel product forms, if this were in fact practical. Given these unique circumstances the exchange of ideas on forging manufacturing techniques and experience, materials data and service experience has been an essential driving force in developing forging techniques and applications in every industrial field. The format of the symposium was similar to that of Williamsburg, focusing on the scope of the subcommittee in the areas of pressure vessel and nuclear forgings, turbine and generator forgings, general industrial forgings, and test methods for forgings. Separate abstracts were prepared for 17 papers.

  14. Connections: Superplasticity, Damascus Steels, Laminated Steels, and Carbon Dating

    NASA Astrophysics Data System (ADS)

    Wadsworth, Jeffrey

    2016-12-01

    In this paper, a description is given of the connections that evolved from the initial development of a family of superplastic plain carbon steels that came to be known as Ultra-High Carbon Steels (UHCS). It was observed that their very high carbon contents were similar, if not identical, to those of Damascus steels. There followed a series of attempts to rediscover how the famous patterns found on Damascus steels blades were formed. At the same time, in order to improve the toughness at room temperature of the newly-developed UHCS, laminated composites were made of alternating layers of UHCS and mild steel (and subsequently other steels and other metals). This led to a study of ancient laminated composites, the motives for their manufacture, and the plausibility of some of the claims relating to the number of layers in the final blades. One apparently ancient laminated composite, recovered in 1837 from the great pyramid of Giza which was constructed in about 2750 B.C., stimulated a carbon dating study of ancient steels. The modern interest in "Bladesmithing" has connections back to many of these ancient weapons.

  15. Atom Interferometer Modeling Tool

    DTIC Science & Technology

    2011-08-08

    definition is to import conductor geometry from an outside CAD tool such as AutoCAD . This allows users to specify the more complex layouts using a...fully-featured tool of their choice, while significantly reducing the complexity of LiveAtom. Furthermore, most groups have already been using a 2D ...specifying conductor geometry LiveAtom offers the user a 3D visualization of their experiment. Once the experiment is fully specified, computing the

  16. 49 CFR 192.55 - Steel pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Steel pipe. 192.55 Section 192.55 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials § 192.55 Steel pipe. (a) New steel pipe is... in accordance with paragraph (c) or (d) of this section. (b) Used steel pipe is qualified for...

  17. 49 CFR 192.55 - Steel pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Steel pipe. 192.55 Section 192.55 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials § 192.55 Steel pipe. (a) New steel pipe is... in accordance with paragraph (c) or (d) of this section. (b) Used steel pipe is qualified for...

  18. 49 CFR 192.55 - Steel pipe.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Steel pipe. 192.55 Section 192.55 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials § 192.55 Steel pipe. (a) New steel pipe is... in accordance with paragraph (c) or (d) of this section. (b) Used steel pipe is qualified for...

  19. 49 CFR 192.55 - Steel pipe.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Steel pipe. 192.55 Section 192.55 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials § 192.55 Steel pipe. (a) New steel pipe is... in accordance with paragraph (c) or (d) of this section. (b) Used steel pipe is qualified for...

  20. 49 CFR 192.55 - Steel pipe.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Steel pipe. 192.55 Section 192.55 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials § 192.55 Steel pipe. (a) New steel pipe is... in accordance with paragraph (c) or (d) of this section. (b) Used steel pipe is qualified for...

  1. Occupational Profiles in the European Steel Industry.

    ERIC Educational Resources Information Center

    Franz, Hans-Werner; And Others

    The steel industry in Europe has faced great changes, with resulting layoffs and restructuring. Now that the most basic changes seem to be over, it has become evident that the remaining steel industry requires more highly trained workers than was the case previously. Although steel maintenance employees were always highly skilled, steel production…

  2. Improving the toughness of ultrahigh strength steel

    SciTech Connect

    Soto, Koji

    2002-01-01

    The ideal structural steel combines high strength with high fracture toughness. This dissertation discusses the toughening mechanism of the Fe/Co/Ni/Cr/Mo/C steel, AerMet 100, which has the highest toughness/strength combination among all commercial ultrahigh strength steels. The possibility of improving the toughness of this steel was examined by considering several relevant factors.

  3. Magnetic sensing for microstructural assessment of power station steels: Magnetic Barkhausen noise and minor loop measurements

    NASA Astrophysics Data System (ADS)

    Wilson, J. W.; Karimian, N.; Yin, W.; Liu, J.; Davis, C. L.; Peyton, A. J.

    2013-06-01

    There are currently no techniques available to monitor the microstructural condition of power station steel components in-service (at elevated temperatures). Electromagnetic (EM) inspection methods have the potential to provide a solution to this problem. Tests have been carried out on power generation steel (P9 and T22) samples with different microstructural states using major and minor B-H loop measurements and correlations established between EM properties and material properties such as Vickers hardness. These correlations will be used to develop a field deployable tool for the quantification of degradation in power station steels.

  4. Muon Tomography as a Tool to Detect Radioactive Source Shielding in Scrap Metal Containers

    NASA Astrophysics Data System (ADS)

    Bonomi, G.; Cambiaghi, D.; Dassa, L.; Donzella, A.; Subieta, M.; Villa, V.; Zenoni, A.; Furlan, M.; Rigoni, A.; Vanini, S.; Viesti, G.; Zumerle, G.; Benettoni, M.; Checchia, P.; Gonella, F.; Pegoraro, M.; Zanuttigh, P.; Calvagno, G.; Calvini, P.; Squarcia, S.

    2014-02-01

    Muon tomography was recently proposed as a tool to inspect large volumes with the purpose of recognizing high density materials immersed in lower density matrices. The MU-STEEL European project (RFCS-CT-2010-000033) studied the application of such a technique to detect radioactive source shielding in truck containers filled with scrap metals entering steel mill foundries. A description of the muon tomography technique, of the MU-STEEL project and of the obtained results will be presented.

  5. Dissimilar Friction Stir Welding Between UNS S31603 Austenitic Stainless Steel and UNS S32750 Superduplex Stainless Steel

    NASA Astrophysics Data System (ADS)

    Theodoro, Maria Claudia; Pereira, Victor Ferrinho; Mei, Paulo Roberto; Ramirez, Antonio Jose

    2015-02-01

    In order to verify the viability of dissimilar UNS S31603 austenitic and UNS S32750 superduplex stainless steels joined by friction stir welding, 6-mm-thick plates were welded using a PCBN-WRe tool. The welded joints were performed in position control mode at rotational speeds of 100 to 300 rpm and a feed rate of 100 mm/min. The joints performed with 150 and 200 rpm showed good appearance and no defects. The metallographic analysis of both joints showed no internal defects and that the material flow pattern is visible only in the stirred zone (SZ) of the superduplex steel. On the SZ top, these patterns are made of regions of different phases (ferrite and austenite), and on the bottom and central part of the SZ, these patterns are formed by alternated regions of different grain sizes. The ferrite grains in the superduplex steel are larger than those in the austenitic ones along the SZ and thermo-mechanically affected zone, explained by the difference between austenite and ferrite recrystallization kinetics. The amount of ferrite islands present on the austenitic steel base metal decreased near the SZ interface, caused by the dissolving of the ferrite in austenitic matrix. No other phases were found in both joints. The best weld parameters were found to be 200 rpm rotation speed, 100 mm/min feed rate, and tool position control.

  6. Friction Stir Lap Welding of Magnesium Alloy to Steel: A Preliminary Investigation

    NASA Astrophysics Data System (ADS)

    Jana, S.; Hovanski, Y.; Grant, G. J.

    2010-12-01

    An initial study was made to evaluate the feasibility of joining magnesium alloy AZ31 sheet to galvanized steel sheet in a lap configuration using friction stir welding (FSW). Two different automotive sheet steels were used for comparative evaluation of the dissimilar joining potential: a 0.8 mm thick, electrogalvanized (EG) mild steel, and a 1.5 mm thick hot-dipped galvanized (HDG) high-strength, low-alloy (HSLA) steel. These steels were joined to 2.33 mm thick AZ31B magnesium sheet. A single FSW tool design was used for both dissimilar welds, and the process parameters were kept the same. The average peak load for the AZ31-1.5 mm steel weld joint in lap shear mode was found to be 6.3 ± 1.0 kN. For the AZ31-0.8 mm steel weld, joint strength was 5.1 ± 1.5 kN. Microstructural investigation indicates melting of the Zn coating present on the steel sheets, and subsequent alloying with the Mg sheet resulted in the formation of a solidified Zn-Mg alloy layer.

  7. Friction Stir Lap Welding of Magnesium Alloy to Steel: A Preliminary Investigation

    SciTech Connect

    Jana, Saumyadeep; Hovanski, Yuri; Grant, Glenn J.

    2010-12-01

    An initial study was made to evaluate the feasibility of joining Magnesium alloy AZ31 sheet to galvanized steel sheet in lap configuration using friction stir welding (FSW). Two different automotive sheet steels were used for comparative evaluation of the dissimilar joining potential; a 0.8mm thick, electro galvanized (EG) mild steel, and a 1.5mm thick hot dipped galvanized (HDG) high-strength, low-alloy steel (HSLA). These steels were joined to 2.33mm thick AZ31B magnesium sheet. A single FSW tool design was used for both dissimilar welds, and process parameters were kept the same. Average peak load for the AZ31-1.5 mm steel weld joint in lap shear mode was found to be 6.3 ± 1.0 kN. For the AZ31-0.8 mm steel weld, joint strength was 5.1 ± 1.5 kN. Microstructural investigation indicates melting of the Zn coating at the interface and subsequent alloying with the Mg sheet resulting in formation of solidified Zn-Mg alloy layer at AZ31/steel interface.

  8. Failure analysis of a tool steel torque shaft

    NASA Technical Reports Server (NTRS)

    Reagan, J. R.

    1981-01-01

    A low design load drive shaft used to deliver power from an experimental exhaust heat recovery system to the crankshaft of an experimental diesel truck engine failed during highway testing. An independent testing laboratory analyzed the failure by routine metallography and attributed the failure to fatigue induced by a banded microstructure. Visual examination by NASA of the failed shaft plus the knowledge of the torsional load that it carried pointed to a 100 percent ductile failure with no evidence of fatigue. Scanning electron microscopy confirmed this. Torsional test specimens were produced from pieces of the failed shaft and torsional overload testing produced identical failures to that which had occurred in the truck engine. This pointed to a failure caused by a high overload and although the microstructure was defective it was not the cause of the failure.

  9. Comparative evaluation of the crack resistance of tool steels

    NASA Astrophysics Data System (ADS)

    Kratovich, L. F.

    1984-08-01

    It is recommended to use as parameters for calculating crack resistance the nominal stress intensity factors: KJ, determined by the method of the J-integral, taking crack growth into account, and Kδ, calculated according to the critical crack opening δc using the theoretical values of the rotational factor. The use of Kδ is preferable because of the conservativeness of the evaluation in the range of operating temperatures of heavy-duty hot-forging dies.

  10. 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.

  11. Welding tritium exposed stainless steel

    SciTech Connect

    Kanne, W.R. Jr.

    1994-11-01

    Stainless steels that are exposed to tritium become unweldable by conventional methods due to buildup of decay helium within the metal matrix. With longer service lives expected for tritium containment systems, methods for welding on tritium exposed material will become important for repair or modification of the systems. Solid-state resistance welding and low-penetration overlay welding have been shown to mitigate helium embrittlement cracking in tritium exposed 304 stainless steel. These processes can also be used on stainless steel containing helium from neutron irradiation, such as occurs in nuclear reactors.

  12. 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).

  13. Advanced steel reheat furnace

    SciTech Connect

    Moyeda, D.; Sheldon, M.; Koppang, R.; Lanyi, M.; Li, X.; Eleazer, B.

    1997-10-01

    Energy and Environmental Research Corp. (EER) under a contract from the Department of Energy is pursuing the development and demonstration of an Advanced Steel Reheating Furnace. This paper reports the results of Phase 1, Research, which has evaluated an advanced furnace concept incorporating two proven and commercialized technologies previously applied to other high temperature combustion applications: EER`s gas reburn technology (GR) for post combustion NOx control; and Air Product`s oxy-fuel enrichment air (OEA) for improved flame heat transfer in the heating zones of the furnace. The combined technologies feature greater production throughput with associated furnace efficiency improvements; lowered NOx emissions; and better control over the furnace atmosphere, whether oxidizing or reducing, leading to better control over surface finish.

  14. GRIPPING TOOL

    DOEpatents

    Sandrock, R.J.

    1961-12-12

    A self-actuated gripping tool is described for transferring fuel elements and the like into reactors and other inaccessible locations. The tool will grasp or release the load only when properly positioned for this purpose. In addition, the load cannot be released except when unsupported by the tool, so that jarring or contact will not bring about accidental release of the load. The gripping members or jaws of the device are cam-actuated by an axially slidable shaft which has two lockable positions. A spring urges the shaft into one position and a solenoid is provided to overcome the spring and move it into the other position. The weight of the tool operates a sleeve to lock the shaft in its existing position. Only when the cable supporting the tool is slack is the device capable of being actuated either to grasp or release its load. (AEC)

  15. Method for welding chromium molybdenum steels

    SciTech Connect

    Sikka, V.K.

    1986-09-16

    A process is described for welding chromium-molybdenum steels which consist of: subjecting the steel to normalization by heating to above the transformation temperature and cooling in air; subjecting the steel to a partial temper by heating to a temperature less than a full temper; welding the steel using an appropriate filler metal; subjecting the steel to a full temper by heating to a temperature sufficient to optimize strength, reduce stress, increase ductility and reduce hardness.

  16. 2169 steel waveform experiments.

    SciTech Connect

    Furnish, Michael David; Alexander, C. Scott; Reinhart, William Dodd; Brown, Justin L.

    2012-11-01

    In support of LLNL efforts to develop multiscale models of a variety of materials, we have performed a set of eight gas gun impact experiments on 2169 steel (21% Cr, 6% Ni, 9% Mn, balance predominantly Fe). These experiments provided carefully controlled shock, reshock and release velocimetry data, with initial shock stresses ranging from 10 to 50 GPa (particle velocities from 0.25 to 1.05 km/s). Both windowed and free-surface measurements were included in this experiment set to increase the utility of the data set, as were samples ranging in thickness from 1 to 5 mm. Target physical phenomena included the elastic/plastic transition (Hugoniot elastic limit), the Hugoniot, any phase transition phenomena, and the release path (windowed and free-surface). The Hugoniot was found to be nearly linear, with no indications of the Fe phase transition. Releases were non-hysteretic, and relatively consistent between 3- and 5-mmthick samples (the 3 mm samples giving slightly lower wavespeeds on release). Reshock tests with explosively welded impactors produced clean results; those with glue bonds showed transient releases prior to the arrival of the reshock, reducing their usefulness for deriving strength information. The free-surface samples, which were steps on a single piece of steel, showed lower wavespeeds for thin (1 mm) samples than for thicker (2 or 4 mm) samples. A configuration used for the last three shots allows release information to be determined from these free surface samples. The sample strength appears to increase with stress from ~1 GPa to ~ 3 GPa over this range, consistent with other recent work but about 40% above the Steinberg model.

  17. JPDR vessel steel examination

    SciTech Connect

    Corwin, W.R.; Broadhead, B.L.; Sokolov, M.A.

    1995-10-01

    There is a need to validate the results of irradiation effects research by the examination of material taken directly from the wall of a pressure vessel which has been irradiated during normal service. This task has been included with the HSSI Program to provide just such an evaluation of material from the wall of the pressure vessel from the JPDR. The JPDR was a small BWR that began operation in 1963. It operated until 1976, accumulating {approximately}17,000 h of operation, of which a little over 14,000 h were with the original 45-MWTh core, and the remaining fraction, late in life, with an upgraded 90-MWTh core. The pressure vessel of the JPDR, fabricated from A 302, grade B, modified steel with an internal weld overlay cladding of 304 stainless steel, is approximately 2 m ID and 73 mm thick. It was fabricated from two shell halves joined by longitudinal seam welds located 180{degrees} from each other. The rolling direction of the shell plates is parallel to the axis of the vessel. It operated at 273{degrees}C and reached a maximum fluence of about 2.3 x 10{sup 18} n/cm{sup 2} (> 1 MeV). The impurity contents in the base metal are 0.10 to 0.11% Cu and 0.010 to 0.017% P with a nickel content of 0.63 to 0.65%. Impurity contents of the weld metal are 0.11 to 0.14% Cu and 0.025 to 0.039% P with a nickel content of 0.59%.

  18. Omics Tools

    SciTech Connect

    Schaumberg, Andrew

    2012-12-21

    The Omics Tools package provides several small trivial tools for work in genomics. This single portable package, the “omics.jar” file, is a toolbox that works in any Java-based environment, including PCs, Macs, and supercomputers. The number of tools is expected to grow. One tool (called cmsearch.hadoop or cmsearch.local), calls the external cmsearch program to predict non-coding RNA in a genome. The cmsearch program is part of the third-party Infernal package. Omics Tools does not contain Infernal. Infernal may be installed separately. The cmsearch.hadoop subtool requires Apache Hadoop and runs on a supercomputer, though cmsearch.local does not and runs on a server. Omics Tools does not contain Hadoop. Hadoop mat be installed separartely The other tools (cmgbk, cmgff, fastats, pal, randgrp, randgrpr, randsub) do not interface with third-party tools. Omics Tools is written in Java and Scala programming languages. Invoking the “help” command shows currently available tools, as shown below: schaumbe@gpint06:~/proj/omics$ java -jar omics.jar help Known commands are: cmgbk : compare cmsearch and GenBank Infernal hits cmgff : compare hits among two GFF (version 3) files cmsearch.hadoop : find Infernal hits in a genome, on your supercomputer cmsearch.local : find Infernal hits in a genome, on your workstation fastats : FASTA stats, e.g. # bases, GC content pal : stem-loop motif detection by palindromic sequence search (code stub) randgrp : random subsample without replacement, of groups randgrpr : random subsample with replacement, of groups (fast) randsub : random subsample without replacement, of file lines For more help regarding a particular command, use: java -jar omics.jar command help Usage: java -jar omics.jar command args

  19. Rebuilding Steam Turbine Generator Reduces Costs at a Steel Mill (Bethlehem Steel Corporation (BSC))

    SciTech Connect

    1999-04-01

    Rebuilding steam turbine generator reduces costs at a steel mill. To remain competitive in the rapidly changing global marketplace, Bethlehem Steel Corporation (BSC), the second largest producer of steel in the United States, was looking for...

  20. Image analysis of corrosion pit initiation on ASTM type A240 stainless steel and ASTM type A 1008 carbon steel

    NASA Astrophysics Data System (ADS)

    Nine, H. M. Zulker

    The adversity of metallic corrosion is of growing concern to industrial engineers and scientists. Corrosion attacks metal surface and causes structural as well as direct and indirect economic losses. Multiple corrosion monitoring tools are available although those are time-consuming and costly. Due to the availability of image capturing devices in today's world, image based corrosion control technique is a unique innovation. By setting up stainless steel SS 304 and low carbon steel QD 1008 panels in distilled water, half-saturated sodium chloride and saturated sodium chloride solutions and subsequent RGB image analysis in Matlab, in this research, a simple and cost-effective corrosion measurement tool has identified and investigated. Additionally, the open circuit potential and electrochemical impedance spectroscopy results have been compared with RGB analysis to gratify the corrosion. Additionally, to understand the importance of ambiguity in crisis communication, the communication process between Union Carbide and Indian Government regarding the Bhopal incident in 1984 was analyzed.

  1. Application of high-rate cutting tools

    NASA Astrophysics Data System (ADS)

    Moriarty, John L., Jr.

    1989-03-01

    Widespread application of the newest high-rate cutting tools to the most appropriate jobs is slowed by the sheer magnitude of developments in tool types, materials, workpiece applications, and by the rapid pace of change. Therefore, a study of finishing and roughing sizes of coated carbide inserts having a variety of geometries for single point turning was completed. The cutting tools were tested for tool life, chip quality, and workpiece surface finish at various cutting conditions with medium alloy steel. An empirical wear-life data base was established, and a computer program was developed to facilitate technology transfer, assist selection of carbide insert grades, and provide machine operating parameters. A follow-on test program was implemented suitable for next generation coated carbides, rotary cutting tools, cutting fluids, and ceramic tool materials.

  2. Hydrogen embrittlement of structural steels.

    SciTech Connect

    Somerday, Brian P.

    2010-06-01

    Carbon-manganese steels are candidates for the structural materials in hydrogen gas pipelines, however it is well known that these steels are susceptible to hydrogen embrittlement. Decades of research and industrial experience have established that hydrogen embrittlement compromises the structural integrity of steel components. This experience has also helped identify the failure modes that can operate in hydrogen containment structures. As a result, there are tangible ideas for managing hydrogen embrittement in steels and quantifying safety margins for steel hydrogen containment structures. For example, fatigue crack growth aided by hydrogen embrittlement is a key failure mode for steel hydrogen containment structures subjected to pressure cycling. Applying appropriate structural integrity models coupled with measurement of relevant material properties allows quantification of safety margins against fatigue crack growth in hydrogen containment structures. Furthermore, application of these structural integrity models is aided by the development of micromechanics models, which provide important insights such as the hydrogen distribution near defects in steel structures. The principal objective of this project is to enable application of structural integrity models to steel hydrogen pipelines. The new American Society of Mechanical Engineers (ASME) B31.12 design code for hydrogen pipelines includes a fracture mechanics-based design option, which requires material property inputs such as the threshold for rapid cracking and fatigue crack growth rate under cyclic loading. Thus, one focus of this project is to measure the rapid-cracking thresholds and fatigue crack growth rates of line pipe steels in high-pressure hydrogen gas. These properties must be measured for the base materials but more importantly for the welds, which are likely to be most vulnerable to hydrogen embrittlement. The measured properties can be evaluated by predicting the performance of the pipeline

  3. Process Hood Stand Support Steel

    SciTech Connect

    VAN KATWIJK, C.

    2000-04-03

    This package is written to comply with EN-6-035-00 for upgrade dedication of commercial grade items (CGI). The SNF-5953 CGI package provides the Technical evaluation to identify the critical characteristics and the acceptance criteria associated with the safety function of the Hood Stand Support Steel. Completion of the technical and quality requirements identified in the dedication package will provide enough data to be reasonably assured that CGI Hood Stand Support Steel will perform its SC function.

  4. Analysis of plasma nitrided steels

    NASA Technical Reports Server (NTRS)

    Salik, J.; Ferrante, J.; Honecy, F.; Hoffman, R., Jr.

    1987-01-01

    The analysis of plasma nitrided steels can be divided to two main categories - structural and chemical. Structural analysis can provide information not only on the hardening mechanisms but also on the fundamental processes involved. Chemical analysis can be used to study the kinetics for the nitriding process and its mechanisms. In this paper preliminary results obtained by several techniques of both categories are presented and the applicability of those techniques to the analysis of plasma-nitrided steels is discussed.

  5. Wear of steel by rubber

    NASA Technical Reports Server (NTRS)

    Gent, A. N.; Pulford, C. T. R.

    1978-01-01

    Wear of a steel blade used as a scraper to abrade rubber surfaces has been found to take place much more rapidly on a cis-polyisoprene (natural rubber) surface than on a cis-polybutadiene surface, and much more rapidly in an inert atmosphere than in air. These observations are attributed to the direct attack upon steel of free-radical species generated by mechanical rupture of elastomer molecules during abrasion.

  6. Wear of steel by rubber

    NASA Technical Reports Server (NTRS)

    Gent, A. N.; Pulford, C. T. R.

    1978-01-01

    Wear of a steel blade used as a scraper to abrade rubber surfaces has been found to take place much more rapidly on a cis-polyisoprene (natural rubber) surface than on a cis-polybutadiene surface, and much more rapidly in an inert atmosphere than in air. These observations are attributed to the direct attack upon steel of free-radical species generated by mechanical rupture of elastomer molecules during abrasion.

  7. Efficient machining of ultra precise steel moulds with freeform surfaces

    NASA Astrophysics Data System (ADS)

    Bulla, B.; Robertson, D. J.; Dambon, O.; Klocke, F.

    2013-09-01

    Ultra precision diamond turning of hardened steel to produce optical quality surfaces can be realized by applying an ultrasonic assisted process. With this technology optical moulds used typically for injection moulding can be machined directly from steel without the requirement to overcoat the mould with a diamond machinable material such as Nickel Phosphor. This has both the advantage of increasing the mould tool lifetime and also reducing manufacture costs by dispensing with the relatively expensive plating process. This publication will present results we have obtained for generating free form moulds in hardened steel by means of ultrasonic assisted diamond turning with a vibration frequency of 80 kHz. To provide a baseline with which to characterize the system performance we perform plane cutting experiments on different steel alloys with different compositions. The baseline machining results provides us information on the surface roughness and on tool wear caused during machining and we relate these to material composition. Moving on to freeform surfaces, we will present a theoretical background to define the machine program parameters for generating free forms by applying slow slide servo machining techniques. A solution for optimal part generation is introduced which forms the basis for the freeform machining experiments. The entire process chain, from the raw material through to ultra precision machining is presented, with emphasis on maintaining surface alignment when moving a component from CNC pre-machining to final machining using ultrasonic assisted diamond turning. The free form moulds are qualified on the basis of the surface roughness measurements and a form error map comparing the machined surface with the originally defined surface. These experiments demonstrate the feasibility of efficient free form machining applying ultrasonic assisted diamond turning of hardened steel.

  8. 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.

  9. Brazing diamond grits onto a steel substrate using copper alloys as the filler metals

    NASA Astrophysics Data System (ADS)

    Chen, S.-M.; Lin, S.-T.

    1996-12-01

    Surface-set diamond tools were fabricated by an active metal brazing process, using bronze (Cu-8.9Sn) powder and 316L stainless steel powder mixed to various ratios as the braze filler metals. The diamond grits were brazed onto a steel substrate at 1050 °C for 30 min in a dry hydrogen atmosphere. After brazing practice, an intermediate layer rich in chromium formed between the braze filler metal and diamond. A braze filler metal composed of 70 wt % bronze powder and 30 wt % stainless steel powder was found to be optimum in that the diamond grits were strongly impregnated in the filler metal by both mechanical and chemical types of holding. The diamond tools thus fabricated performed better than conventional nickel-plated diamond tools. In service, the braze filler metal wore at almost the same rate as the diamond grits, and no pullout of diamond grits or peeling of the filler metal layer took place.

  10. Green Tool

    EPA Pesticide Factsheets

    The Green Tool represents infiltration-based stormwater control practices. It allows modelers to select a BMP type, channel shape and BMP unit dimensions, outflow control devices, and infiltration method. The program generates an HSPF-formatted FTABLE.

  11. Friction stir processing on high carbon steel U12

    SciTech Connect

    Tarasov, S. Yu. Rubtsov, V. E.; Melnikov, A. G.

    2015-10-27

    Friction stir processing (FSP) of high carbon steel (U12) samples has been carried out using a milling machine and tools made of cemented tungsten carbide. The FSP tool has been made in the shape of 5×5×1.5 mm. The microstructural characterization of obtained stir zone and heat affected zone has been carried out. Microhardness at the level of 700 MPa has been obtained in the stir zone with microstructure consisting of large grains and cementitte network. This high-level of microhardness is explained by bainitic reaction developing from decarburization of austenitic grains during cementite network formation.

  12. Shrinkage Prediction for the Investment Casting of Stainless Steels

    SciTech Connect

    Sabau, Adrian S

    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.

  13. The Bendability of Ultra High strength Steels

    NASA Astrophysics Data System (ADS)

    Hazra, S. K.; Efthymiadis, P.; Alamoudi, A.; Kumar, R. L. V.; Shollock, B.; Dashwood, R.

    2016-08-01

    Automotive manufacturers have been reducing the weight of their vehicles to meet increasingly stringent environmental legislation that reflects public demand. A strategy is to use higher strength materials for parts with reduced cross-sections. However, such materials are less formable than traditional grades. The frequent result is increased processing and piece costs. 3D roll forming is a novel and flexible process: it is estimated that a quarter of the structure of a vehicle can be made with a single set of tooling. Unlike stamping, this process requires material with low work hardening rates. In this paper, we present results of ultra high strength steels that have low elongation in a tension but display high formability in bending through the suppression of the necking response.

  14. Laser cleaning of steel for paint removal

    NASA Astrophysics Data System (ADS)

    Chen, G. X.; Kwee, T. J.; Tan, K. P.; Choo, Y. S.; Hong, M. H.

    2010-11-01

    Paint removal is an important part of steel processing for marine and offshore engineering. For centuries, a blasting techniques have been widely used for this surface preparation purpose. But conventional blasting always has intrinsic problems, such as noise, explosion risk, contaminant particles, vibration, and dust. In addition, processing wastes often cause environmental problems. In recent years, laser cleaning has attracted much research effort for its significant advantages, such as precise treatment, and high selectivity and flexibility in comparison with conventional cleaning techniques. In the present study, we use this environmentally friendly technique to overcome the problems of conventional blasting. Processed samples are examined with optical microscopes and other surface characterization tools. Experimental results show that laser cleaning can be a good alternative candidate to conventional blasting.

  15. Relationship between Material Properties and Local Formability of DP980 Steels

    SciTech Connect

    Choi, Kyoo Sil; Soulami, Ayoub; Li, Dongsheng; Sun, Xin; Khaleel, Mohammad A.; Xu, Le; Barlat, Frederic

    2012-04-24

    A noticeable degree of inconsistent forming behaviors has been observed for the 1st generation advanced high strength steels (AHSS) in production, and they appear to be associated with the inherent microstructural-level inhomogeneities for various AHSS. This indicates that the basic material property requirements and screening methods currently used for the mild steels and high strength low alloys (HSLA) are no longer sufficient for qualifying today’s AHSS. In order to establish more relevant material acceptance criteria for AHSS, the fundamental understandings on key mechanical properties and microstructural features influencing the local formability of AHSS need to be developed. For this purpose, in this study, DP980 was selected as model steels and eight different types of DP980 sheet steels were acquired from various steel suppliers. Various experiments were then performed on the eight different DP980 steels such as chemical composition analysis, static tensile test, hole expansion test, channel forming test. Scanning electron microscope (SEM) pictures of the DP980 steels were also obtained, and image processing tools were then adopted to those SEM pictures in order to quantify their various microstructural features. The results show that all DP980 steels show large discrepancy in their performance and that the tensile properties and hole expansion properties of these steels do not correlate with their local formability. According to the results up to date, it is not possible to correlate the microstructural features alone to the macroscopically measured deformation behaviors. In addition to image analysis, other experiments (i.e., nano-indentation test) are also planned to quantify the individual phase properties of the various DP steels.

  16. Impact behavior of reduced-activation steels irradiated to 24 dpa*1

    NASA Astrophysics Data System (ADS)

    Klueh, R. L.; Alexander, D. J.

    1996-10-01

    Charpy impact tests were previously conducted on eight chromium-tungsten steels after irradiation at 365°C to 6-8 and 15-17 dpa in the Fast Flux Test Facility. These same steels, which range in concentration from 2.25 to 12 wt% (all steels contained 0.1%C), have now been irradiated to 20-24 dpa under the same conditions. Post-irradiation Charpy impact tests after 20-24 dpa showed that the loss of impact toughness, as measured by an increase in the ductile—brittle transition temperature (DBTT) and a decrease in the upper-shelf energy, remained relatively unchanged from the values after 15-17 dpa. As before, the most irradiation-resistant steels were two 9% Cr steels: the DBTT of a 9Cr2W0.25V steel increased 59°C, and for the same composition with an addition of 0.07% Ta, the DBTT increased only 21°C. The other steels developed shifts in DBTT of 100 to 300°C. A 2.25% Cr steel with 2% W and 0.25% V was less severely affected by irradiation than 2.25% Cr steels with 0.25% V and no tungsten, 2% W and no vanadium, and with 1% W and 0.25% V. Steels with 5 and 12% Cr, 2% W, and 0.25% V had properties between those of the 2.25Cr and 9Cr steels.

  17. Numerical modelling of tool wear in turning with cemented carbide cutting tools

    SciTech Connect

    Franco, P.; Estrems, M.; Faura, F.

    2007-04-07

    A numerical model is proposed for analysing the flank and crater wear resulting from the loss of material on cutting tool surface in turning processes due to wear mechanisms of adhesion, abrasion and fracture. By means of this model, the material loss along cutting tool surface can be analysed, and the worn surface shape during the workpiece machining can be determined. The proposed model analyses the gradual degradation of cutting tool during turning operation, and tool wear can be estimated as a function of cutting time. Wear-land width (VB) and crater depth (KT) can be obtained for description of material loss on cutting tool surface, and the effects of the distinct wear mechanisms on surface shape can be studied. The parameters required for the tool wear model are obtained from bibliography and experimental observation for AISI 4340 steel turning with WC-Co cutting tools.

  18. Silica exposure in hand grinding steel castings.

    PubMed

    O'Brien, D; Froehlich, P A; Gressel, M G; Hall, R M; Clark, N J; Bost, P; Fischbach, T

    1992-01-01

    Exposure to silica dust was studied in the grinding of castings in a steel foundry that used conventional personal sampling methods and new real-time sampling techniques developed for the identification of high-exposure tasks and tools. Approximately one-third of the personal samples exceeded the National Institute for Occupational Safety and Health recommended exposure limit for crystalline silica, a fraction similar to that identified in other studies of casting cleaning. Of five tools used to clean the castings, the tools with the largest wheels, a 6-in. grinder and a 4-in. cutoff wheel, were shown to be the major sources of dust exposure. Existing dust control consisted of the use of downdraft grinding benches. The size of the casting precluded working at a distance close enough to the grates of the downdraft benches for efficient capture of the grinding dust. In addition, measurements of air recirculated from the downdraft benches indicated that less than one-half of the respirable particles were removed from the contaminated airstream. Previous studies have shown that silica exposures in the cleaning of castings can be reduced or eliminated through the use of mold coatings, which minimize sand burn-in on the casting surface; by application of high-velocity, low-volume exhaust hoods; and by the use of a nonsilica molding aggregate such as olivine. This study concluded that all these methods would be appropriate control options.

  19. Review on Cold-Formed Steel Connections

    PubMed Central

    Tan, Cher Siang; Mohammad, Shahrin; Md Tahir, Mahmood; Shek, Poi Ngian

    2014-01-01

    The concept of cold-formed light steel framing construction has been widespread after understanding its structural characteristics with massive research works over the years. Connection serves as one of the important elements for light steel framing in order to achieve its structural stability. Compared to hot-rolled steel sections, cold-formed steel connections perform dissimilarity due to the thin-walled behaviour. This paper aims to review current researches on cold-formed steel connections, particularly for screw connections, storage rack connections, welded connections, and bolted connections. The performance of these connections in the design of cold-formed steel structures is discussed. PMID:24688448

  20. Review on cold-formed steel connections.

    PubMed

    Lee, Yeong Huei; Tan, Cher Siang; Mohammad, Shahrin; Tahir, Mahmood Md; Shek, Poi Ngian

    2014-01-01

    The concept of cold-formed light steel framing construction has been widespread after understanding its structural characteristics with massive research works over the years. Connection serves as one of the important elements for light steel framing in order to achieve its structural stability. Compared to hot-rolled steel sections, cold-formed steel connections perform dissimilarity due to the thin-walled behaviour. This paper aims to review current researches on cold-formed steel connections, particularly for screw connections, storage rack connections, welded connections, and bolted connections. The performance of these connections in the design of cold-formed steel structures is discussed.

  1. 38. Photocopy of photograph. STEEL PLANT, BOILERS UNDER CONSTRUCTION IN ...

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

    38. Photocopy of photograph. STEEL PLANT, BOILERS UNDER CONSTRUCTION IN BOILER PLANT LOCATED EAST OF MAIN STEEL PLANT, 1909. (From the Bethlehem Steel Corporation collection, Seattle, WA) - Irondale Iron & Steel Plant, Port Townsend, Jefferson County, WA

  2. Choice of Heat Treatment Regimes for Welded Joints of Preliminarily Mechanically Hardened Steels

    NASA Astrophysics Data System (ADS)

    Mazukhina, E. A.; Priymak, E. Yu.; Gryzunov, V. I.; Firsova, N. V.

    2015-05-01

    Results of an evaluation of the possibility of the use of electrically welded cold-drawn pipe billets from steels 09GSF and 22GYu for making drill pipes with welded-on tool joint are presented. The structure and properties of friction-welded joints are studied in the initial condition and after annealing. The effect of the annealing on the strength characteristics of the joints is considered. The results of the study are used to recommend the steel for the production of a pilot batch of drill pipes with welded-on tool joints and field testing.

  3. Optimization and testing results of Zr-bearing ferritic steels

    SciTech Connect

    Tan, Lizhen; Yang, Ying; Tyburska-Puschel, Beata; Sridharan, K.

    2014-09-01

    The mission of the Nuclear Energy Enabling Technologies (NEET) program is to develop crosscutting technologies for nuclear energy applications. Advanced structural materials with superior performance at elevated temperatures are always desired for nuclear reactors, which can improve reactor economics, safety margins, and design flexibility. They benefit not only new reactors, including advanced light water reactors (LWRs) and fast reactors such as sodium-cooled fast reactor (SFR) that is primarily designed for management of high-level wastes, but also life extension of the existing fleet when component exchange is needed. Developing and utilizing the modern materials science tools (experimental, theoretical, and computational tools) is an important path to more efficient alloy development and process optimization. Ferritic-martensitic (FM) steels are important structural materials for nuclear reactors due to their advantages over other applicable materials like austenitic stainless steels, notably their resistance to void swelling, low thermal expansion coefficients, and higher thermal conductivity. However, traditional FM steels exhibit a noticeable yield strength reduction at elevated temperatures above ~500°C, which limits their applications in advanced nuclear reactors which target operating temperatures at 650°C or higher. Although oxide-dispersion-strengthened (ODS) ferritic steels have shown excellent high-temperature performance, their extremely high cost, limited size and fabricability of products, as well as the great difficulty with welding and joining, have limited or precluded their commercial applications. Zirconium has shown many benefits to Fe-base alloys such as grain refinement, improved phase stability, and reduced radiation-induced segregation. The ultimate goal of this project is, with the aid of computational modeling tools, to accelerate the development of a new generation of Zr-bearing ferritic alloys to be fabricated using conventional

  4. Authoring Tools

    NASA Astrophysics Data System (ADS)

    Treviranus, Jutta

    Authoring tools that are accessible and that enable authors to produce accessible Web content play a critical role in web accessibility. Widespread use of authoring tools that comply to the W3C Authoring Tool Accessibility Guidelines (ATAG) would ensure that even authors who are neither knowledgeable about nor particularly motivated to produce accessible content do so by default. The principles and techniques of ATAG are discussed. Some examples of accessible authoring tools are described including authoring tool content management components such as TinyMCE. Considerations for creating an accessible collaborative environment are also covered. As part of providing accessible content, the debate between system-based personal optimization and one universally accessible site configuration is presented. The issues and potential solutions to address the accessibility crisis presented by the advent of rich internet applications are outlined. This challenge must be met to ensure that a large segment of the population is able to participate in the move toward the web as a two-way communication mechanism.

  5. Analysis of acoustic emission signals at austempering of steels using neural networks

    NASA Astrophysics Data System (ADS)

    Łazarska, Malgorzata; Wozniak, Tadeusz Z.; Ranachowski, Zbigniew; Trafarski, Andrzej; Domek, Grzegorz

    2017-05-01

    Bearing steel 100CrMnSi6-4 and tool steel C105U were used to carry out this research with the steels being austempered to obtain a martensitic-bainitic structure. During the process quite a large number of acoustic emissions (AE) were observed. These signals were then analysed using neural networks resulting in the identification of three groups of events of: high, medium and low energy and in addition their spectral characteristics were plotted. The results were presented in the form of diagrams of AE incidence as a function of time. It was demonstrated that complex transformations of austenite into martensite and bainite occurred when austempering bearing steel at 160 °C and tool steel at 130 °C respectively. The selected temperatures of isothermal quenching of the tested steels were within the area near to MS temperature, which affected the complex course of phase transition. The high activity of AE is a typical occurrence for martensitic transformation and this is the transformation mechanism that induces the generation of AE signals of higher energy in the first stage of transition. In the second stage of transformation, the initially nucleated martensite accelerates the occurrence of the next bainitic transformation.

  6. Method of Making Steel Strapping and Strip

    SciTech Connect

    1999-12-10

    Fact sheet written for the Inventions and Innovation Program about a new method for making steel strapping and strip from rod stock produced from scrap steel. There is a large movement in the American steel industry to utilize more recycled steel. Recycled steel melted in the electric arc furnaces of mini-mills is being used as the source of raw materials for an increasing number of products, largely due to its lower price. However, conventional processes for producing steel strapping and cold-rolled strip steel restrict manufacturers from using more than 50% recycled steel. In addition, steel strapping and cold-rolled strip steel traditionally require many production steps. They are produced from primary steel that has been cast into slab, heated, rolled to achieve the desired thickness, and slit to the desired width. The slitting process produces microcracks along the edge of the strapping or strip, which reduce tensile strength. A new continuous process produces steel strapping and 1/2 inch to 6 inch strip steel from the rod and strip stock made from scrap steel in mini-mills. The new process creates steel strapping and strip with improved strength and quality due to the absence of microcracks caused by the conventional slitting process. The finished product is cheaper because of the lower cost associated with using rod ad lower conversion costs. In addition, the higher tensile strength of the product allows for thinner strapping. The process represents a new approach to producing any steel strapping used for bundling and packaging items for storage or transport. In addition, this innovative new process can be used to produce cold-rolled strip steel, a basic raw material for automobile parts, hardware, office equipment, and many other products.

  7. The microstructure of chromium-tungsten steels

    NASA Astrophysics Data System (ADS)

    Klueh, R. L.; Maziasz, P. J.

    1989-03-01

    Chromium-tungsten steels are being developed to replace the Cr-Mo steels for fusion-reactor applications. Eight experimental steels were produced and examined by optical and electron microscopy. Chromium concentrations of 2.25, 5, 9 and 12 pct were used. Steels with these chromium compositions and with 2 pct W and 0.25 pct V were produced. To determine the effect of tungsten and vanadium, three other 2.25Cr steels were produced as follows: an alloy with 2 pct W and 0 pct V and alloys with 0 and 1 pct W and 0.25 pct V. A 9Cr steel containing 2 pct W, 0.25 pct V, and 0.07 pct Ta also was studied. For all alloys, carbon was maintained at 0.1 pct. Two pct tungsten was required in the 2.25Cr steels to produce 100 pct bainite (no polygonal ferrite). The 5Cr and 9Cr steels were 100 pct martensite, but the 12Cr steel contained about 25 pct delta-ferrite. Precipitate morphology and precipitate types varied, depending on the chromium content. For the 2.25Cr steels, M3C and M7C3 were the primary precipitates; for the 9Cr and 12Cr steels, M23C6 was the primary precipitate. The 5Cr steel contained M7C3 and M23C6. All of the steels with vanadium also contained MC.

  8. A novel Mo-W interlayer approach for CVD diamond deposition on steel

    NASA Astrophysics Data System (ADS)

    Kundrát, Vojtěch; Zhang, Xiaoling; Cooke, Kevin; Sun, Hailin; Sullivan, John; Ye, Haitao

    2015-04-01

    Steel is the most widely used material in engineering for its cost/performance ratio and coatings are routinely applied on its surface to further improve its properties. Diamond coated steel parts are an option for many demanding industrial applications through prolonging the lifetime of steel parts, enhancement of tool performance as well as the reduction of wear rates. Direct deposition of diamond on steel using conventional chemical vapour deposition (CVD) processes is known to give poor results due to the preferential formation of amorphous carbon on iron, nickel and other elements as well as stresses induced from the significant difference in the thermal expansion coefficients of those materials. This article reports a novel approach of deposition of nanocrystalline diamond coatings on high-speed steel (M42) substrates using a multi-structured molybdenum (Mo) - tungsten (W) interlayer to form steel/Mo/Mo-W/W/diamond sandwich structures which overcome the adhesion problem related to direct magnetron sputtering deposition of pure tungsten. Surface, interface and tribology properties were evaluated to understand the role of such an interlayer structure. The multi-structured Mo-W interlayer has been proven to improve the adhesion between diamond films and steel substrates by acting as an effective diffusion barrier during the CVD diamond deposition.

  9. Correlation of FEA Prediction And Experiments On Dual-Phase Steel Automotive Rails

    SciTech Connect

    Du, C.; Chen, X. M.; Lim, T.; Chang, T.; Xiao, P.; Liu, S.-D.

    2007-05-17

    The North American Auto/Steel Partnership (A/SP) High-Strength Steel Forming Project Team has been studying the impact of advanced high-strength steels on stamping of structural components. Tooling was built to evaluate the effect of different grades of dual-phase steels on rail type stampings. The formed panels were laser scanned and the amount of springback was measured against the design intention. FEA simulation of the forming process was carried out to validate the numerical modeling techniques in the large and complex dual-phase steel stampings. The materials used in the study were Dual-Phase (DP) Steels DP600, DP780 and DP980. The FEA solver used was LS-Dyna version 971. The simulation results were correlated with the measurement data under various forming conditions including forming methods, trimming, binder and pad pressures. Reasonably good correlations were obtained across different grades of steels in terms of flange opening angles, wall opening angles, twist angles and dimensional deviations.

  10. A novel Mo-W interlayer approach for CVD diamond deposition on steel

    SciTech Connect

    Kundrát, Vojtěch; Sullivan, John; Ye, Haitao; Zhang, Xiaoling; Cooke, Kevin; Sun, Hailin

    2015-04-15

    Steel is the most widely used material in engineering for its cost/performance ratio and coatings are routinely applied on its surface to further improve its properties. Diamond coated steel parts are an option for many demanding industrial applications through prolonging the lifetime of steel parts, enhancement of tool performance as well as the reduction of wear rates. Direct deposition of diamond on steel using conventional chemical vapour deposition (CVD) processes is known to give poor results due to the preferential formation of amorphous carbon on iron, nickel and other elements as well as stresses induced from the significant difference in the thermal expansion coefficients of those materials. This article reports a novel approach of deposition of nanocrystalline diamond coatings on high-speed steel (M42) substrates using a multi-structured molybdenum (Mo) – tungsten (W) interlayer to form steel/Mo/Mo-W/W/diamond sandwich structures which overcome the adhesion problem related to direct magnetron sputtering deposition of pure tungsten. Surface, interface and tribology properties were evaluated to understand the role of such an interlayer structure. The multi-structured Mo-W interlayer has been proven to improve the adhesion between diamond films and steel substrates by acting as an effective diffusion barrier during the CVD diamond deposition.

  11. Influence of Various Material Design Parameters on Deformation Behaviors of TRIP Steels

    SciTech Connect

    Choi, Kyoo Sil; Soulami, Ayoub; Liu, Wenning N.; Sun, Xin; Khaleel, Mohammad A.

    2010-11-02

    In this paper, the microstructure-based finite element modeling method is used as a virtual design tool in investigating the respective influence of various material design parameters on the deformation behaviors of transformation induced plasticity (TRIP) steels. For this purpose, the separate effects of several different material design parameters, such as the volume fraction and stability of austenite phase and the strengths of the constituent phases, on the ultimate tensile strength (UTS) and ductility/formability of TRIP steels are quantitatively examined using different representative volume elements (RVEs) representing different TRIP steels. The computational results suggest that higher austenite stability is helpful in enhancing the ductility and formability of TRIP steels by delaying the martensitic transformation to a later stage, whereas increase of austenite volume fraction and/or ferrite strength alone is not beneficial to improve the performance of TRIP steels. The results in this study also indicate that various material design parameters must be adjusted concurrently to develop high performance TRIP steels. For example, the austenite strength should increase over the ferrite strength in order to induce the gradual/smooth martensitic transformation, and the strength disparity between the ferrite and the freshly-formed martensite phases should decrease in order to avoid higher stress/strain concentration along the phase boundaries. The modeling approach and results presented in this paper can be helpful in providing the deformation fundamentals for the development of high performance TRIP steels.

  12. Submerged arc fillet welds between mild steel and stainless steel

    SciTech Connect

    Kotecki, D.J.; Rajan, V.B.

    1997-02-01

    Submerged arc fillet welds between mild steel and Type 304 stainless steel, made with ER309L wire, may contain no ferrite and be at risk of hot cracking, or they may be sufficiently diluted that they transform to martensite with both hot cracking risk and low ductility. This situation is most prevalent when direct current electrode positive (DCEP) polarity is used and when the flange is the mild steel part of the T-joint. A flux that adds chromium to the weld can somewhat alleviate this tendency. Direct current electrode negative (DCEN) polarity greatly reduces this tendency by limiting dilution. Fillet weld compositions and dilutions are obtained for a number of welding conditions and fluxes.

  13. Robot Tools

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Mecanotron, now division of Robotics and Automation Corporation, developed a quick-change welding method called the Automatic Robotics Tool-change System (ARTS) under Marshall Space Flight Center and Rockwell International contracts. The ARTS system has six tool positions ranging from coarse sanding disks and abrasive wheels to cloth polishing wheels with motors of various horsepower. The system is used by fabricators of plastic body parts for the auto industry, by Texas Instruments for making radar domes, and for advanced composites at Aerospatiale in France.

  14. Management Tools

    NASA Technical Reports Server (NTRS)

    1987-01-01

    Manugistics, Inc. (formerly AVYX, Inc.) has introduced a new programming language for IBM and IBM compatible computers called TREES-pls. It is a resource management tool originating from the space shuttle, that can be used in such applications as scheduling, resource allocation project control, information management, and artificial intelligence. Manugistics, Inc. was looking for a flexible tool that can be applied to many problems with minimal adaptation. Among the non-government markets are aerospace, other manufacturing, transportation, health care, food and beverage and professional services.

  15. 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

  16. 29 CFR 1926.754 - Structural steel assembly.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 8 2013-07-01 2013-07-01 false Structural steel assembly. 1926.754 Section 1926.754 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Steel Erection § 1926.754 Structural steel...) Tripping hazards. Shear connectors (such as headed steel studs, steel bars or steel lugs), reinforcing...

  17. 29 CFR 1926.754 - Structural steel assembly.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Structural steel assembly. 1926.754 Section 1926.754 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Steel Erection § 1926.754 Structural steel...) Tripping hazards. Shear connectors (such as headed steel studs, steel bars or steel lugs), reinforcing...

  18. 29 CFR 1926.754 - Structural steel assembly.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 8 2011-07-01 2011-07-01 false Structural steel assembly. 1926.754 Section 1926.754 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Steel Erection § 1926.754 Structural steel...) Tripping hazards. Shear connectors (such as headed steel studs, steel bars or steel lugs), reinforcing...

  19. 29 CFR 1926.754 - Structural steel assembly.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 8 2012-07-01 2012-07-01 false Structural steel assembly. 1926.754 Section 1926.754 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Steel Erection § 1926.754 Structural steel...) Tripping hazards. Shear connectors (such as headed steel studs, steel bars or steel lugs), reinforcing...

  20. 29 CFR 1926.754 - Structural steel assembly.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 8 2014-07-01 2014-07-01 false Structural steel assembly. 1926.754 Section 1926.754 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Steel Erection § 1926.754 Structural steel...) Tripping hazards. Shear connectors (such as headed steel studs, steel bars or steel lugs), reinforcing...

  1. Steel erected at A-3 Test Stand

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Workers erect the first fabricated steel girders to arrive at the A-3 Test Stand at Stennis Space Center. Steel work began at the construction site Oct. 29 and is scheduled to continue into next spring.

  2. Steel erected at A-3 Test Stand

    NASA Image and Video Library

    2008-10-29

    Workers erect the first fabricated steel girders to arrive at the A-3 Test Stand at Stennis Space Center. Steel work began at the construction site Oct. 29 and is scheduled to continue into next spring.

  3. Steel erected at A-3 Test Stand

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Workers erect the first fabricated steel girders to arrive at the A-3 Test Stand at Stennis Space Center. Steel work began at the construction site Oct. 29 and is scheduled to continue into next spring.

  4. High-temperature brazing of stainless steel

    NASA Technical Reports Server (NTRS)

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

    1978-01-01

    Prevention of iron contamination of platens is eliminated by placing alumina/silica ceramic-fiber blankets between platens and carbon-steel plate. Carbon-steel plates provide rigidity and improve heat transfer.

  5. Electromechanical Surface Hardening of Tubing Steels

    NASA Astrophysics Data System (ADS)

    Fedorova, L. V.; Fedorov, S. K.; Serzhant, A. A.; Golovin, V. V.; Systerov, S. V.

    2017-07-01

    Results of metallographic studies of the structure of steels 38G2S and 37G2F and steels of group D after electromechanical surface hardening of tube specimens over the external diameter are presented.

  6. Corrosion control of steel-reinforced concrete

    NASA Astrophysics Data System (ADS)

    Chung, D. D. L.

    2000-10-01

    The methods and materials for corrosion control of steel-reinforced concrete are reviewed. The methods are steel surface treatment, the use of admixtures in concrete, surface coating on concrete, and cathodic protection.

  7. High-temperature brazing of stainless steel

    NASA Technical Reports Server (NTRS)

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

    1978-01-01

    Prevention of iron contamination of platens is eliminated by placing alumina/silica ceramic-fiber blankets between platens and carbon-steel plate. Carbon-steel plates provide rigidity and improve heat transfer.

  8. New Development of HSLA Steels in China

    NASA Astrophysics Data System (ADS)

    Zhang, Xiao-gang; Yang, Cai-fu; Shang, Cheng-jia

    During the last decade, the adjustment and upgrade of steel product structures always be very important tasks in China's iron and steel industry. Since there is a fast growth of steel production in China, a series of research achievements in the technology area of HSLA steels have been made and applied successfully in the actual production, and thereby promoted a rapid development and application of China's HSLA Steel products. However, The China's iron and steel industry is now facing the excess production capacity and under pressure from respects of resource, energy and environment, therefore, it would be an effective way to realize the sustainable development in China's iron and steel industry by strengthening the applications of HSLA steels continuously and positively.

  9. Design tools

    Treesearch

    Anton TenWolde; Mark T. Bomberg

    2009-01-01

    Overall, despite the lack of exact input data, the use of design tools, including models, is much superior to the simple following of rules of thumbs, and a moisture analysis should be standard procedure for any building envelope design. Exceptions can only be made for buildings in the same climate, similar occupancy, and similar envelope construction. This chapter...

  10. Friction Stir Brazing: a Novel Process for Fabricating Al/Steel Layered Composite and for Dissimilar Joining of Al to Steel

    NASA Astrophysics Data System (ADS)

    Zhang, Guifeng; Su, Wei; Zhang, Jianxun; Wei, Zhongxin

    2011-09-01

    A novel process of friction stir brazing (FSB) for fabricating Al/steel layered composite (by multipass) and for joining Al to steel (by single pass) was proposed to avoid the wear of pin by steel, in which a tool without pin was used. FSB of 1.8-mm-thick Al sheet to steel sheet was conducted using a cylindrical tool with 20-mm diameter but without pin and using 0.1-mm-thick zinc foil as filler metal. For the rotational speed of 1500 rpm, sound joints were reliably obtained at the medium range of traverse speed of 75 to 235 mm/min, which fractured within Al parent sheet during tensile shear test. Furthermore, for peel test on the sound joints, Al and steel parent sheets tended to crack and deform, respectively. Metallographic examination showed that most Zn was extruded and the resultant interfacial structure consisted of several Al-Fe intermetallic compounds (IMCs) with a little Zn, less than 3 at. pct. The thickness of IMCs can be controlled to be less than 10 μm by properly increasing traverse speed ( e.g., 150 mm/min). The metallurgical process of FSB was investigated by observing the microstructure of the longitudinal section of a friction stir brazed joint obtained by the suddenly stopping technique.

  11. Developments in HSLA steel products

    NASA Astrophysics Data System (ADS)

    Paules, John R.

    1991-01-01

    The technology of microalloyed steels is expanding beyond its original emphasis on low-carbon, severely control-rolled strip and plate products. A variety of economical, high-strength, tough, as-rolled or as-forged microalloyed products are replacing more expensive heat-treated steels. Recrystallization-controlled rolling is being utilized to produce very fine ferrite grain sizes and good toughness in strip, plate and bar products processed with relatively high rolling temperatures. High-strength microalloyed long products such as railroad joint bars, truck frame rails and flat bars for truck trailer construction are replacing heat-treated parts. Microalloyed, medium-carbon forging steels are used extensively for automobile engine and suspension components. Fully pearlitic high-carbon rods are being microalloyed to enhance the properties of wire and springs.

  12. ESF GROUND SUPPORT - STRUCTURAL STEEL ANALYSIS

    SciTech Connect

    T. Misiak

    1996-06-26

    The purpose and objective of this analysis are to expand the level of detail and confirm member sizes for steel sets included in the Ground Support Design Analysis, Reference 5.20. This analysis also provides bounding values and details and defines critical design attributes for alternative configurations of the steel set. One possible configuration for the steel set is presented. This analysis covers the steel set design for the Exploratory Studies Facility (ESF) entire Main Loop 25-foot diameter tunnel.

  13. Corrosion Behavior of Steel Fibrous Concrete

    DTIC Science & Technology

    1977-05-01

    Crvtaiue wi ,rerse sido it necessaty m’d Identify by block number) steel fibrous concrete corrosion cracked fibrous concrete 20 ABST RACT (Continue...dissolved gas in liq- Although chloride ions affect the rate of steel corro- uids. sion in concrete , corrosion can occur without them. Verbeck has...repcrted that steel subjected to a concrete Corrosion of steel will not occur without water. Not environment normally develops a protective oxide film

  14. Study of residual stress distribution in the machined stainless steel components

    NASA Astrophysics Data System (ADS)

    Jang, Dong Y.; Liou, J.; Cho, U.

    1994-07-01

    The demand for high quality and fully automated production, coupled with advances in alloy development, focuses attention on the surface condition of products, especially the residual stresses on the machined surface because of its effect on component performance, longevity, and reliability. Although stainless steel is an important material with wide application, it is not easy to obtain a favorable surface condition due to its sensitivity to thermal and mechanical operations. In order to obtain favorable surface conditions in a stainless steel component, it is necessary to have practical data which include information concerning tool wear, surface roughness and surface residual stress. In the research toward developing a machinability chart which can provide suitable cutting parameters for the high production rate and good quality surface, and can be used in computer controlled machining tools, surface residual stress distributions in the turning process for stainless steel were studied. Austenitic 304 stainless steel bars were selected as the workpieces and uncoated carbide tools were used in the tests. The obtained results will show residual stress conditions on the machined stainless steel components varying according to cutting conditions.

  15. Steel erected at A-3 Test Stand

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Fabricated steel began arriving by truck Oct. 24 for construction of the A-3 Test Stand that will be used to test the engine for the nation's next generation of moon rockets. Within days workers from Lafayette Steel Erector Inc. began assembling the 16 steel stages needed on the foundation and footings poured in the previous year.

  16. Recycling steel automatically - through resource recovery

    SciTech Connect

    Foley, W.J.

    1997-12-01

    Last year, more than 55 percent of all steel cans were recycled. But no matter how effective the local recycling programs may be, some steel cans and other steel products are overlooked and appear in MSW. This missed steel fraction is automatically recycled by resource recovery facilities through magnetic separation. More than three-fourths of the operating resource recovery plants magnetically separate steel cans and other discarded steel items either pre- or post-combustion. Recovering ferrous scrap clearly reduces the post-combustion material that is landfilled and heightens the facilities` environmental performance. Both the resource recovery and steel industries must heighten public awareness of the benefits of automatic steel recycling. Magnetic separation at resource recovery facilities is a simple method of diverting what would otherwise be relegated as solid waste to the landfill. It should be recognized as an increasingly important and valued part of the resource recovery and steel industries` overall recycling efforts. This paper will discuss the status of steel can recycling in the United States, describe how recovered ferrous is beneficiated before recycling by the steel industry, and make recommendations for heightening awareness of the steel recycling contribution made by resource recovery facilities.

  17. Steel erected at A-3 Test Stand

    NASA Image and Video Library

    2008-10-24

    Fabricated steel began arriving by truck Oct. 24 for construction of the A-3 Test Stand that will be used to test the engine for the nation's next generation of moon rockets. Within days workers from Lafayette Steel Erector Inc. began assembling the 16 steel stages needed on the foundation and footings poured in the previous year.

  18. Steel erected at A-3 Test Stand

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Fabricated steel began arriving by truck Oct. 24 for construction of the A-3 Test Stand that will be used to test the engine for the nation's next generation of moon rockets. Within days workers from Lafayette Steel Erector Inc. began assembling the 16 steel stages needed on the foundation and footings poured in the previous year.

  19. Steeling and Resilience in Art Education

    ERIC Educational Resources Information Center

    Heise, Donalyn

    2014-01-01

    Steel is an incredibly strong alloy of iron and carbon. Due to its incredible strength and durability, this resilient material is commonly used for constructing buildings. The transitive verb "steeling" is defined in Miriam-Webster dictionary as "to fill with resolution or determination, as in, she 'steeled herself to face the…

  20. Steeling and Resilience in Art Education

    ERIC Educational Resources Information Center

    Heise, Donalyn

    2014-01-01

    Steel is an incredibly strong alloy of iron and carbon. Due to its incredible strength and durability, this resilient material is commonly used for constructing buildings. The transitive verb "steeling" is defined in Miriam-Webster dictionary as "to fill with resolution or determination, as in, she 'steeled herself to face the…

  1. Steel: Price and Policy Issues

    DTIC Science & Technology

    2006-08-31

    semi-finished slab steel. It has no U.S. production assets, though it acquired the leading Canadian producer, Dofasco , in January 2006 and earlier was...Bloomberg.com, “Mittal Makes $22.7 Bln. Unsolicited Bid for Arcelor” (Jan. 27, 2006); Wall St. Journal, “Arcelor Transfers Dofasco Unit to Block...Stelco 56 Canada Y 4.54 4.91 Dofasco 60 Canada Y 4.19 4.99 Steel Dynamics 76 USA Y 3.28 3.15 Altos Hornos de Mexico 78 Mexico Y 3.24 3.01 Ipsco 82 USA

  2. Metallography of maraging 350 steel

    SciTech Connect

    Hutson, S.M.; Merten, C.W.

    1987-01-01

    A technique for etching maraging 350 steel with Glyceregia is described. Surface activation procedures are integral to this technique. Microstructural features revealed by this technique are compared with those obtained with Kalling's reagent, Fry's reagent, and 5% Nital, three etchants commonly used to reveal microstructures of maraging steels. Features which may be simultaneously revealed using Glyceregia include prior austenite grain boundaries, martensitic structure, precipitates, titanium carbo-nitrides, and reverted austenite. The other etchants examined in this investigation typically reveal only a few of the microstructural features detailed above at any one time. 11 refs., 10 figs., 2 tabs.

  3. Plating on stainless steel alloys

    SciTech Connect

    Dini, J.W.; Johnson, H.R.

    1981-09-11

    Quantitative adhesion data are presented for a variety of electroplated stainless steel type alloys. Results show that excellent adhesion can be obtained by using a Wood's nickel strike or a sulfamate nickel strike prior to final plating. Specimens plated after Wood's nickel striking failed in the deposit rather than at the interface between the substrate and the coating. Flyer plate quantitative tests showed that use of anodic treatment in sulfuric acid prior to Wood's nickel striking even further improved adhesion. In contrast activation of stainless steels by immersion or cathodic treatment in hydrochloric acid resulted in very reduced bond strengths with failure always occurring at the interface between the coating and substrate.

  4. Feasibility study of fluxless brazing cemented carbides to steel

    NASA Astrophysics Data System (ADS)

    Tillmann, W.; Sievers, N.

    2017-03-01

    One of the most important brazing processes is the joints between cemented carbides and steel for the tool industry such as in rotary drill hammers or saw blades. Even though this technique has already been used for several decades, defects in the joint can still occur and lead to quality loss. Mostly, the joining process is facilitated by induction heating and the use of a flux to enhance the wetting of the filler alloy on the surface of the steel and cemented carbide in an ambient atmosphere. However, although the use of flux enables successful joining, it also generates voids within the joint, which reduces the strength of the connection while the chemicals within the flux are toxic and polluting. In this feasibility study, a fluxless brazing process is used to examine the joint between cemented carbides and steel for the first time. For this, ultrasound is applied during induction heating to enable the wetting between the liquid filler metal and the surfaces of the cemented carbide and steel. The ultrasound generates cavitations within the liquid filler metal, which remove the oxides from the surface. Several filler metals such as a silver based alloy Ag449, pure Zn, and an AlSi-alloy were used to reduce the brazing temperature and to lower the thermal residual stresses within the joint. As a result, every filler metal successfully wetted both materials and led to a dense connection. The ultrasound has to be applied carefully to prevent a damage of the cemented carbide. In this regard, it was observed that single grains of the cemented carbide broke out and remained in the joint. This positive result of brazing cemented carbides to steel without a flux but using ultrasound, allows future studies to focus on the shear strength of these joints as well as the behavior of the thermally induced residual stresses.

  5. Pulmonary fibrosis and exposure to steel welding fume.

    PubMed

    Cosgrove, M P

    2015-12-01

    Arc welders who have been exposed to high concentrations of steel welding fume for prolonged periods of time may develop pulmonary fibrosis but the nature of the fibrotic changes has been debated over the last 80 years without any clear international consensus. To characterize the nature of the pulmonary fibrosis that develops in response to steel welding fume exposure and to provide a working hypothesis that would explain the findings of the existing research, to provide a platform for future research and to inform future occupational and clinical management of welders with pulmonary effects from welding fume. Review of the world literature on pulmonary fibrosis and welding of steel in all languages using PubMed, with further secondary search of references in the articles found in the primary search. Google and Reference Manager were used as further confirmatory search tools. Only case series and case reports were found but these provided consistent evidence that the consequence of exposure to steel welding fume at high levels for a prolonged period of time is a type of pulmonary fibrosis similar to, and possibly the same as, respiratory bronchiolitis which eventually develops into desquamative interstitial pneumonia with ongoing exposure. Steel welding fume may cause an occupational respiratory bronchiolitis which may develop into de squamative interstitial pneumonia with ongoing exposure. This concept may explain the difficulties in interpreting the wider literature on welding fume and lung function at lower exposures and may also explain the increased risk of lung cancer in welders. © The Author 2015. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. Teaching Steel Connections Using an Interactive Virtual Steel Sculpture

    ERIC Educational Resources Information Center

    Moaveni, Saeed; Chou, Karen C.

    2015-01-01

    Steel connections play important roles in the integrity of a structure, and many structural failures are attributed to connection failures. Connections are the glue that holds a structure together. The failures of the Hartford Coliseum in 1977, the Hyatt Regency Hotel in Kansas City in 1980, and the I-35W Bridge in Minneapolis in 2007 are all…

  7. Teaching Steel Connections Using an Interactive Virtual Steel Sculpture

    ERIC Educational Resources Information Center

    Moaveni, Saeed; Chou, Karen C.

    2015-01-01

    Steel connections play important roles in the integrity of a structure, and many structural failures are attributed to connection failures. Connections are the glue that holds a structure together. The failures of the Hartford Coliseum in 1977, the Hyatt Regency Hotel in Kansas City in 1980, and the I-35W Bridge in Minneapolis in 2007 are all…

  8. 1993 Evaluation of steel ring standards for magnetic particle inspection

    SciTech Connect

    Bates, B.; Hagemaier, D.; Petty, J.; Armstrong, C.

    1996-10-01

    The Ketos ring standard manufactured from AISI Type 01 (.90 carbon) tool steel has become part of certain US magnetic particle standards such as MIL-STD-1949. The rings are used to verify system performance and for sensitivity evaluation for magnetic particle materials. Some controversy exists concerning the use of the steel ring as a reference standard for the following reasons: inconsistencies in hole detectability have been noted between various rings caused by differences in magnetic permeability as a result of variations in annealing; the use of magnetic particle indication evaluation for ring standard certification is subject to variations in particle concentration, sensitivity, and visual subjectivity; and the proposed introduction of new materials in the manufacture of ring standards. This report describes an evaluation of rings manufactured of different materials and different annealed states. A suggested method for qualifying a newly manufactured ring as a certified reference standard is also described.

  9. Monitoring microstructural evolution in irradiated steel with second harmonic generation

    SciTech Connect

    Matlack, Kathryn H.; Kim, Jin-Yeon; Jacobs, Laurence J.; Wall, James J.; Qu, Jianmin

    2015-03-31

    Material damage in structural components is driven by microstructural evolution that occurs at low length scales and begins early in component life. In metals, these microstructural features are known to cause measurable changes in the acoustic nonlinearity parameter. Physically, the interaction of a monochromatic ultrasonic wave with microstructural features such as dislocations, precipitates, and vacancies, generates a second harmonic wave that is proportional to the acoustic nonlinearity parameter. These nonlinear ultrasonic techniques thus have the capability to evaluate initial material damage, particularly before crack initiation and propagation occur. This paper discusses how the nonlinear ultrasonic technique of second harmonic generation can be used as a nondestructive evaluation tool to monitor microstructural changes in steel, focusing on characterizing neutron radiation embrittlement in nuclear reactor pressure vessel steels. Current experimental evidence and analytical models linking microstructural evolution with changes in the acoustic nonlinearity parameter are summarized.

  10. Effect of parameters in diode laser welding of steel sheets

    NASA Astrophysics Data System (ADS)

    Kujanpaeae, Veli; Maaranen, Petteri; Kostamo, Tapio

    2003-03-01

    Austenitic stainless steel sheets and ordinary cold-rolled carbon steel sheets with variable thickness were welded with 1 kW diode laser. Different weld joints were utilized. The optimal parameters for each case were determined. The joints were examined by metallography and mechanical testing. The results show that diode laser is an optimal tool for sheet metal welding, when a considerable narrow weld is aimed. The edges prepared by mechanical sheering are acceptable as the joint preparation. The tensile strength and ductility of all the joints were acceptable and on the same level or better than that of base metal. The shielding gas seems to play a much higher role than in conventional laser welding (CO2 or Nd:YAG laser welding). When using the non-oxidizing shielding gas (nitrogen or argon), the welding speed to be reached is much slower than when welding without any shielding gas. This is probably due to the increase of absorption by oxygen.

  11. Diamond turning of aspheric steel molds for optics replication

    NASA Astrophysics Data System (ADS)

    Klocke, F.; Dambon, O.; Bulla, B.

    2010-02-01

    Diamond turning of steel parts is conventionally not possible due to the high tool wear. However this process would enable several different application with high economical innovative potential. One technology that enables the direct manufacturing of steel components with monocrystalline diamond is the ultrasonic assisted diamond turning process. This technology has been investigated over years within the Fraunhofer IPT and has proven its potential. Surface roughness in the range of Ra = 5 nm are reached and the diamond wear is reduced by a factor 100 or higher. Up to now this process has been investigated in lab conditions manufacturing only plane surfaces. In order to prove its industrial suitability, two relevant aspherical shapes, convex and concave respectively, have been defined and manufactured. The reached form accuracies and surface roughness values will be described in this paper.

  12. Isothermal superplastic boronizing of high carbon and low alloy steels

    SciTech Connect

    Xu, C.H.; Gao, W.; Xi, J.K.

    1996-02-01

    Superplasticity has been developed rapidly since the 1960`s. Superplasticity and superplastic deformation technique of steel and ferrous alloys offer a new method of forming complex parts for industrial applications, such as dies and gears. On the other hand, boronizing has long been used to improve the surface properties of dies and tools because boride has high hardness, good wear resistance, and good corrosion and oxidation resistance. Superplastic boronizing, a new technique, is the processes that combines boronizing with superplastic deformation. Because two processes become one, energy and time can be saved. In the present paper, the superplastic boronizing processes for commercial 0.9C-1Si-1Cr-Fe and 1C-1Cr-Fe steels are described first. Then, the microstructure and properties of specimens produced by using superplastic and conventional boronizing are compared. Finally, a physical model for superplastic boronizing processes is suggested.

  13. SQA(TM): Surface Quality Assured Steel Bar Program

    SciTech Connect

    Chang, Tzyy-Shuh; Shi, Jianjun; Zhou, Shiyu

    2009-03-03

    OG Technologies, Inc. (OGT) has led this SQA (Surface Quality Assured Steel Bar) program to solve the major surface quality problems plaguing the US special quality steel bars and rods industry and their customers, based on crosscutting sensors and controls technologies. Surface defects in steel formed in a hot rolling process are one of the most common quality issues faced by the American steel industry, accounting for roughly 50% of the rejects or 2.5% of the total shipment. Unlike other problems such as the mechanical properties of the steel product, most surface defects are sporadic and cannot be addressed based on sampling techniques. This issue hurts the rolling industry and their customers in their process efficiency and operational costs. The goal of this program is to develop and demonstrate an SQA prototype, with synergy of HotEye® and other innovations, that enables effective rolling process control and efficient quality control. HotEye®, OGT’s invention, delivers high definition images of workpieces at or exceeding 1,450°C while the workpieces travel at 100 m/s. The elimination of surface defect rejects will be achieved through the integration of imaging-based quality assessment, advanced signal processing, predictive process controls and the integration with other quality control tools. The SQA program team, composed of entities capable of and experienced in (1) research, (2) technology manufacturing, (3) technology sales and marketing, and (4) technology end users, is very strong. There were 5 core participants: OGT, Georgia Institute of Technology (GIT), University of Wisconsin (UW), Charter Steel (Charter) and ArcelorMittal Indiana Harbor (Inland). OGT served as the project coordinator. OGT participated in both research and commercialization. GIT and UW provided significant technical inputs to this SQA project. The steel mills provided access to their rolling lines for data collection, design of experiments, host of technology test and

  14. Downhole tool

    DOEpatents

    Hall, David R.; Muradov, Andrei; Pixton, David S.; Dahlgren, Scott Steven; Briscoe, Michael A.

    2007-03-20

    A double shouldered downhole tool connection comprises box and pin connections having mating threads intermediate mating primary and secondary shoulders. The connection further comprises a secondary shoulder component retained in the box connection intermediate a floating component and the primary shoulders. The secondary shoulder component and the pin connection cooperate to transfer a portion of makeup load to the box connection. The downhole tool may be selected from the group consisting of drill pipe, drill collars, production pipe, and reamers. The floating component may be selected from the group consisting of electronics modules, generators, gyroscopes, power sources, and stators. The secondary shoulder component may comprises an interface to the box connection selected from the group consisting of radial grooves, axial grooves, tapered grooves, radial protrusions, axial protrusions, tapered protrusions, shoulders, and threads.

  15. Spray-formed tooling for injection molding and die casting applications

    SciTech Connect

    K. M. McHugh; B. R. Wickham

    2000-06-26

    Rapid Solidification Process (RSP) Tooling{trademark} is a spray forming technology tailored for producing molds and dies. The approach combines rapid solidification processing and net-shape materials processing in a single step. The ability of the sprayed deposit to capture features of the tool pattern eliminates costly machining operations in conventional mold making and reduces turnaround time. Moreover, rapid solidification suppresses carbide precipitation and growth, allowing many ferritic tool steels to be artificially aged, an alternative to conventional heat treatment that offers unique benefits. Material properties and microstructure transformation during heat treatment of spray-formed H13 tool steel are described.

  16. Spray-formed Tooling for Injection Molding and Die Casting Applications

    SciTech Connect

    Mc Hugh, Kevin Matthew

    2000-06-01

    Rapid Solidification Process (RSP) ToolingTM is a spray forming technology tailored for producing molds and dies. The approach combines rapid solidification processing and net-shape materials processing in a single step. The ability of the sprayed deposit to capture features of the tool pattern eliminates costly machining operations in conventional mold making and reduces turnaround time. Moreover, rapid solidification suppresses carbide precipitation and growth, allowing many ferritic tool steels to be artificially aged, an alternative to conventional heat treatment that offers unique benefits. Material properties and microstructure transformation during heat treatment of spray-formed H13 tool steel are described.

  17. 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.

  18. Surface modification of SKD-61 steel by ion implantation technique

    SciTech Connect

    Wen, F. L.; Lo, Y.-L.; Yu, Y.-C.

    2007-07-15

    The purpose of this study is to investigate how ion implantation affects the surface characteristics and nitrogenizing depth of the thin film by the use of a NEC 9SDH-2 3 MV Pelletron accelerator that implants nitrogen ions into SKD-61 tool steels for surface modification. Nitrogen ions were implanted into the surface layer of materials so that the hardness of modified films could be improved. Also, the nitride film stripping problems of the traditional nitrogenizing treatment could be overcome by a new approach in surface process engineering. As nitrogen ions with high velocity impacted on the surface of the substrate, the ions were absorbed and accumulated on the surface of the substrate. The experiments were performed with two energies (i.e., 1 and 2 MeV) and different doses (i.e., 2.5x10{sup 15}, 7.5x10{sup 15}, and 1.5x10{sup 16} ions/cm{sup 2}). Nitrogen ions were incorporated into the interface and then diffused through the metal to form a nitride layer. Analysis tools included the calculation of stopping and range of ions in matter (SRIM), the detection of a secondary ion mass spectrometry (SIMS), and nanoindentation testing. Through the depth analysis of SIMS, the effects of the ion-implanted SKD-61 steels after heating at 550 deg. C in a vacuum furnace were examined. The nanoindenting results indicate the variation of hardness of SKD-61 steels with the various ion doses. It reaches two to three times the original hardness of SKD-61 steels.

  19. Bearing steels in the 21. century

    SciTech Connect

    Tsubota, Kazuichi; Sato, Toshio; Kato, Yoshiyuki; Hiraoka, Kazuhiko; Hayashi, Ryoji

    1998-12-31

    Oxygen content of bearing steel will be reduced to below 3 ppm in the year 2000 if the current trend for the reduction of oxygen in the steel continues. As a result, size of oxide inclusions will become smaller and the fatigue life will be doubled. From the viewpoint of life prediction, cleanliness evaluation methods currently used are not effective. Inclusion Rating Method by Statistics of Extreme is useful for both cleanliness evaluation and fatigue life prediction. Bearings made of suitably heat treated carbon steels or low alloy steels, which possess equivalent fatigue properties to bearing steels, will increase owing to the requirement for lower cost and better formability.

  20. Influence of Additional Electrical Current on Machinability of BN Free-Machining Steel in Turning

    NASA Astrophysics Data System (ADS)

    Tanaka, Ryutaro; Lin, Yongchuan; Hosokawa, Akira; Ueda, Takashi; Yamada, Keiji

    It is widely known that the electromotive force generated at the interface between the cutting tool and work material, during a metal cutting process, influences the cutting mechanism. Previously published papers describe the influence of the passage of electric current through the contact zone between cutting tool and work material, on tool life in cutting several work materials. However, few papers deal with the influence of this electric current on the behavior of a deposited layer called “belag”, observed in turning work materials such as calcium deoxidized steel and boron and nitrogen, BN added steel. This paper deals with the machinability of BN free-machining steel in turning with a supplied current of various values and different directions of flow. The test materials were, BN added steel based AISI 1045 which has good machinability at high cutting speed and standard AISI 1045. Turning was undertaken using one of three types of cutting tool; K10 and P30 carbide and cermet. The power source for additional current supply was a direct current source and the maximum current flowing in the circuit was 20milliamperes (mA). To investigate the influence of supplied current on the characteristics of the turning process, tool life, cutting force and cutting temperature were determined experimentally. When turning with carbide P30 the maximum crater depth in the tool was reduced drastically when the value of supplied current reached 5mA, regardless of its direction of flow, compared with depths at lower current values. This suggests that the additional electrical current promotes generation of the protective layer, on the rake face, in turning BN free-machining steel.

  1. Reduced-activation steels: Future development for improved creep strength

    NASA Astrophysics Data System (ADS)

    Klueh, R. L.

    2008-08-01

    Reduced-activation steels for fusion applications were developed in the 1980s to replace the elevated-temperature commercial steels first considered. The new steels were patterned after the commercial steels, with the objective that the new steels have yield stress and ultimate tensile strength and impact toughness in a Charpy test comparable to or better than the steels they replaced. That objective was achieved in reduced-activation steels developed in Japan, Europe, and the United States. Although tensile and impact toughness of the reduced-activation steels exceed those of the commercial steels they were patterned after, their creep-rupture properties are inferior to some commercial steels they replaced. They are even more inferior to commercial steels developed since the 1980s. In this paper, compositional differences between reduced-activation steels and new commercial steels are examined, and compositions are proposed for development of new-and-improved reduced-activation steels.

  2. Improved the microstructures and properties of M3:2 high-speed steel by spray forming and niobium alloying

    SciTech Connect

    Lu, L.; Hou, L.G.; Zhang, J.X.; Wang, H.B.; Cui, H.; Huang, J.F.; Zhang, Y.A.; Zhang, J.S.

    2016-07-15

    The microstructures and properties of spray formed (SF) high-speed steels (HSSs) with or without niobium (Nb) addition were studied. Particular emphasis was placed on the effect of Nb on the solidification microstructures, decomposition of M{sub 2}C carbides, thermal stability and mechanical properties. The results show that spray forming can refine the cell size of eutectic carbides due to the rapid cooling effect during atomization. With Nb addition, further refinement of the eutectic carbides and primary austenite grains are obtained. Moreover, the Nb addition can accelerate the decomposition of M{sub 2}C carbides and increase the thermal stability of high-speed steel, and also can improve the hardness and bending strength with slightly decrease the impact toughness. The high-speed steel made by spray forming and Nb alloying can give a better tool performance compared with powder metallurgy M3:2 and commercial AISI M2 high-speed steels. - Highlights: • Spray forming can effectively refine the microstructure of M3:2 steel. • Niobium accelerates the decomposition of M{sub 2}C carbides. • Niobium increases the hardness and bending strength of spray formed M3:2 steel. • Spray-formed niobium-containing M3:2 steel has the best tool performance.

  3. Precision machining of steel decahedrons

    NASA Technical Reports Server (NTRS)

    Abernathy, W. J.; Sealy, J. R.

    1972-01-01

    Production of highly accurate decahedron prisms from hardened stainless steel is discussed. Prism is used to check angular alignment of mounting pads of strapdown inertial guidance system. Accuracies obtainable using recommended process and details of operation are described. Photographic illustration of production device is included.

  4. Effect of nitrogen on the stabilization of austenite in a tungsten-molybdenum high-speed steel

    SciTech Connect

    Popandopulo, A.N.; Zhukova, L.T.

    1986-05-01

    A study was made of the tendency of steels R6M5 and R6Am5 to austenite stabilization after subzero treatment and high-temperature tempering in hot-rolled bars. Data indicate that in steel R6AM5 during quenching there is almost instantaneous austenite stabilization. The data was derived from a study of phase composition (exposure from a microsection in DRON-2.0 equipment in iron K /SUB alpha/ radiation), microstructure, and hardness. The authors conclude that in view of serious difficulties in metallurgical and tool production, steel R6AM5 should be supplied only at the request of the customer.

  5. Structure and properties of tungsten-free high-speed steel 8M3F3S

    NASA Astrophysics Data System (ADS)

    Smol'nikov, E. A.; Volosova, T. A.; Baranova, L. I.

    1981-07-01

    Lowering the carbon content of tungsten-free high-speed steel 8M3F3S of the 'EI277 and 'EI260 type leads to better mechanical and technological properties (the red hardness increases, the optimal range of quenching temperatures is broader) and reduces the amount of retained austenite after quenching.The addition of silicon also improves the mechanical properties and the wear resistance of tools and the grindability of the steel.

  6. STEFINS: a steel freezing integral simulation program

    SciTech Connect

    Frank, M.V.

    1980-09-01

    STEFINS (STEel Freezing INtegral Simulation) is a computer program for the calculation of the rate of solidification of molten steel on solid steel. Such computations arize when investigating core melt accidents in fast reactors. In principle this problem involves a coupled two-dimensional thermal and hydraulic approach. However, by physically reasonable assumptions a decoupled approach has been developed. The transient solidification of molten steel on a cold wall is solved in the direction normal to the molten steel flow and independent from the solution for the molten steel temperature and Nusselt number along the direction of flow. The solutions to the applicable energy equations have been programmed in cylindrical and slab geometries. Internal gamma heating of steel is included.

  7. Dendritic inhomogeneity of stainless maraging steels

    SciTech Connect

    Krasnikova, S.I.; Drobot, A.V.; Shmelev, A.Y.; Vukelich, S.B.

    1986-03-01

    The authors investigated dendritic inhomogeneity in industrial ingots 630 mm (steel I) in diameter and 500 mm (steel II) in diameter. The variation in the degree of dendritic inhomogeneity was investigated over the height of the ingots and across the sections on an MS-46 microprobe. It was established that the elements can be placed in the following order in accordance with the degree of reduction in the liquation factor: titanium, molybdenum, nickel, chromium, and cobalt. Titanium and molybdenum exhibit forward liquation in both steels, and chromium in steel II. The distribution of nickel and chromium in the steel I ingots and cobalt in the steel II ingots is unconventional. Dendritic inhomogeneity, which must be considered in assigning the heat treatment for finished articles, develops during the crystallization of stainless maraging steels.

  8. Thermal Linear Expansion of Nine Selected AISI Stainless Steels

    DTIC Science & Technology

    1978-04-01

    stainless steels. The nine selected stainless steels are AISI 303, 304, 304L, 316, 317, 321, 347, 410 , and 430. The recoended values Include the...point of the stainless steels. The nine selected stainless steels are AISI 303, 304, 304L, 316, 317, 321, 347, 410 , and 430. The recommended values...Stainless Steel..................................26 8. AISI 410 Stainless Steel..................................29 9. AISI 430 Stainless Steel

  9. White Layer Formation Due to Phase Transformation to Orthogonal machine of AISI 1045 Annealed Steel

    SciTech Connect

    Han, Sangil; Melkote, Shreyes N; Haluska, Dr. Michael S; Watkins, Thomas R

    2008-01-01

    It is commonly believed that the white layer formed during machining of steels is caused primarily by a thermally induced phase transformation resulting from rapid heating and quenching. As a result, it is often assumed that if the temperature at the tool flank-workpiece interface exceeds the nominal phase transformation temperature for the steel, a white layer forms. However, no attempt has been made to actually measure the temperatures produced at the tool flank-workpiece interface and correlate it with microstructural evidence of phase transformation. This paper aims to address these limitations through suitably designed experiments and analysis. Orthogonal machining tests were performed on AISI 1045 annealed steel at different cutting speeds and tool flank wear. During machining, temperature measurements at the tool flank-workpiece interface were made using an exposed thermocouple technique. Metallographic studies of the machined sub-surface and X-ray diffraction (XRD) measurements were performed to determine the presence and depth of white layer, and the presence of the retained austenite phase in the machined surface layer, respectively. Analysis of the data shows that the white layer can form due to phase transformation at temperatures below the nominal austenitization temperature of the steel. Possible causes of this result are presented.

  10. Use of RSP Tooling to Manufacture Die Casting Dies

    SciTech Connect

    Kevin McHugh

    2004-07-01

    The technology and art used to construct die casting dies has seen many improvements over the years. However, the time lag from when a design is finalized to the time a tool is in production has remained essentially the same. The two main causes for the bottleneck are the need to qualify a part design by making prototypes (usually from an alternative process), and the production tooling lead time after the prototypes are approved. Production tooling costs are high due to the labor and equipment costs associated with transforming a forged block of tool steel into a finished tool. CNC machining, sink EDM, benching, engraving and heat treatment unit operations are typically involved. As a result, there is increasing interest in rapid tooling (RT) technologies that shorten the design-to-part cycle and reduce the cost of dies. There are currently more than 20 RT methods being developed and refined around the world (1). The "rapid" in rapid tooling suggests time compression for tool delivery, but does not address robustness as nearly all RT approaches are intended for low-volume prototype work, primarily for molding plastics. Few options exist for die casting. An RT technology suitable for production-quality tooling in the time it normally takes for prototype tooling is highly desirable. In fact, there would be no need for a distinction between prototype and production tooling. True prototype parts could be made using the same processing conditions and materials intended for production. Qualification of the prototype part would allow the manufacturer to go directly into production with the same tool. A relatively new RT technology, Rapid Solidification Process (RSP) Tooling, is capable of making production-quality tooling in an RT timeframe for die casting applications. RSP Tooling, was developed at the Idaho National Engineering and Environmental Laboratory (INEEL), and commercialized with the formation of RSP Tooling, LLC (2). This paper describes the process, and

  11. Fatigue Strength Restoration in Corrosion Pitted 4340 Alloy Steel Via Low Plasticity Burnishing

    DTIC Science & Technology

    2006-01-01

    at far lower cost7. LPB can be performed on conventional and CNC machine tools at costs and speeds comparable to those in conventional machining ...typical multi-axis CNC machining operation. Fatigue Strength Restoration in Corrosion Pitted 4340 Alloy Steel via Low Plasticity Burnishing Page -4...distribution produced. This allows application of the process at the highest practical CNC machining speeds. Figure 2 - LPB tool being used in four

  12. Tool Gear: Infrastructure for Parallel Tools

    SciTech Connect

    May, J; Gyllenhaal, J

    2003-04-17

    Tool Gear is a software infrastructure for developing performance analysis and other tools. Unlike existing integrated toolkits, which focus on providing a suite of capabilities, Tool Gear is designed to help tool developers create new tools quickly. It combines dynamic instrumentation capabilities with an efficient database and a sophisticated and extensible graphical user interface. This paper describes the design of Tool Gear and presents examples of tools that have been built with it.

  13. Comparative Structural Strength Research of Hardened Carbon Steel and Hot-Rolled Alloy Steel

    NASA Astrophysics Data System (ADS)

    Bogomolov, A. V.; Zhakupov, A. N.; Kanayev, A. T.; Sikach, I. A.; Tugumov, K. K.

    2016-08-01

    Experiments on quantitative evaluation of fatigue strength showed that St5ps and St5sp carbon steels with A400 strength class can be fully applied for erection of constructions and buildings having cyclical loads during operation. Study of corrosion resistance of hardened carbon steel in comparison with hot-rolled alloy steel consists in difference in structures and hence, difference in intensity of electric and chemical processes featuring presence of steel in concrete. Structure of St5sp steel with A400 strength class in surface area has significantly less corrosion rate than ferritic-perlitic structure of 35GS steel with A400 strength class.

  14. Graphite fiber reinforced structure for supporting machine tools

    DOEpatents

    Knight, Jr., Charles E.; Kovach, Louis; Hurst, John S.

    1978-01-01

    Machine tools utilized in precision machine operations require tool support structures which exhibit minimal deflection, thermal expansion and vibration characteristics. The tool support structure of the present invention is a graphite fiber reinforced composite in which layers of the graphite fibers or yarn are disposed in a 0/90.degree. pattern and bonded together with an epoxy resin. The finished composite possesses a low coefficient of thermal expansion and a substantially greater elastic modulus, stiffness-to-weight ratio, and damping factor than a conventional steel tool support utilized in similar machining operations.

  15. Synthesizing and Characterizing a Waterborne Polyaniline for Corrosion Protection of Steels

    NASA Astrophysics Data System (ADS)

    Pan, Tongyan; Yu, Qifeng; Miao, Tao

    2015-02-01

    This study explores the idea of synthesizing and characterizing a new intrinsically conducting polyaniline that at the molecular level carries a hydrophilic component, making the polymer highly waterborne and thereby applicable to massive production for corrosion protection of steels. The waterborne polyaniline was mixed in a water-based epoxy and then coated on SAE 1008/1010 steel samples for evaluating its anti-corrosion capacity using a powerful surface-analysis tool, Scanning Kelvin Probe Force Microscopy (SKPFM). The high resolution surface topography and corrosion potential of steel samples coated with the Polyaniline-based primer, as studied by SKPFM, show significantly lower corrosion activities than two control groups: uncoated steel samples and epoxy-only coated samples that were also subjected to SKPFM analyses under the same corrosive condition. The surface analysis results indicate that this new waterborne polyaniline is capable of protecting steels from corrosion when mixed in conventional water-based epoxies, opening the door to the development of an economical and long-life coating for corrosion protection of steel structures.

  16. Durable metal carbide layers on steels formed by ion implantation at high temperatures

    NASA Astrophysics Data System (ADS)

    Singer, I. L.; Bolster, R. N.; Sprague, J. A.; Kim, K.; Ramalingam, S.; Jeffries, R. A.; Ramseyer, G. O.

    1985-08-01

    High-power beams (4-10 W/cm2) of Ti ions have been used to heat Fe and steel substrates to 600-800 °C during high fluence (5×1017/cm2) implantation. Auger sputter depth profiles find a stoichiometric TiC surface layer, about 100 nm deep, graded continuously into both Fe and steel substrates. Secondary ion mass spectrometry of Fe and steels implanted in 13CO atmospheres indicate that the carbon originates from the bulk in carbon steels but from the atmosphere in Fe foils. Transmission electron microscopy reveals a continuous layer of fine-grained (50-100 nm) TiC crystallites in a preferred Baker-Nutting orientation relationship with respect to underlying Fe grains. Abrasive-wear measurements performed with diamond paste (1-5 μm) show the TiC layer on hardened M2 steel is 3-10 times more wear resistant than the substrate. Sliding-wear studies find an extremely durable layer that reduces friction by up to 60%, and increases by 50% the contact-stress threshold of M2 tool steel to boundary lubrication. The metallurgical processes responsible for the TiC layer will be discussed, and the advantages of this high-temperature treatment will be presented.

  17. Dissimilar Al/steel friction stir welding lap joints for automotive applications

    NASA Astrophysics Data System (ADS)

    Campanella, D.; Spena, P. Russo; Buffa, G.; Fratini, L.

    2016-10-01

    A widespread usage of aluminum alloys for the fabrication of car-body parts is conditional on the employment of appropriate welding methods, especially if dissimilar welding must be performed with automotive steel grades. Dissimilar welding of aluminum alloys and steel grades poses some issues concerning the formation of brittle intermetallic compounds, difference in physical and chemical properties of the parent metals, and poor wetting behavior of aluminum. Friction stir welding is considered to be a reasonable solution to obtain sound aluminum/steel joints. A study on the join quality of dissimilar lap joints of steel and aluminum alloy sheets after friction stir welding is proposed here. A low carbon steel is joined with AA6016 aluminum alloy to study preliminarily the feasibility to assembly car-body parts. The joints, welded with tool rotation and feed rate varying in a wide range, have been studied from a visual examination and microstructural point of view. Optical microscopy has been used to characterize the microstructure of the examined sheets in as-received and welded conditions. Micro-hardness measurements have been carried out to quantitatively analyze the local hardness of the welded joints. Set welding process parameters are identified to assemble without the presence of macroscopic defects the examined steel and aluminum welded parts.

  18. Influence of Processing and Heat Treatment on Corrosion Resistance and Properties of High Alloyed Steel Coatings

    NASA Astrophysics Data System (ADS)

    Hill, Horst; Weber, Sebastian; Raab, Ulrich; Theisen, Werner; Wagner, Lothar

    2012-09-01

    Corrosion and abrasive wear are two important aspects to be considered in numerous engineering applications. Looking at steels, high-chromium high-carbon tool steels are proper and cost-efficient materials. They can either be put into service as bulk materials or used as comparatively thin coatings to protect lower alloyed construction or heat treatable steels from wear and corrosion. In this study, two different corrosion resistant tool steels were used for the production of coatings and bulk material. They were processed by thermal spraying and super solidus liquid phase sintering as both processes can generally be applied to produce coatings on low alloyed substrates. Thermally sprayed (high velocity oxygen fuel) coatings were investigated in the as-processed state, which is the most commonly used condition for technical applications, and after a quenching and tempering treatment. In comparison, sintered steels were analyzed in the quenched and tempered condition only. Significant influence of alloy chemistry, processing route, and heat treatment on tribological properties was found. Experimental investigations were supported by computational thermodynamics aiming at an improvement of tribological and corrosive resistance.

  19. Hydraulic tool

    SciTech Connect

    Gregory, J.T.

    1988-04-05

    A hydraulic force-delivering tool including a cylinder, a piston slidable in the cylinder and a hydraulic pump to deliver fluid under pressure to the cylinder the hydraulic pump is described, comprising: a pump body; means forming a cylindrical chamber in the pump body; at least one inlet port opening into one end of the chamber from outside the body; means forming an outlet port at the other end of the chamber; a check valve in the outlet port enabling outward flow only; a pump rod plunger reciprocable through a given stroke in the chamber; inner and outer concentric cylindrical surfaces in the chamber and on the plunger, respectively; an annular shoulder on the chamber inner cylindrical surface facing toward the other end of the chamber; an annular seal member slidable along the pump rod and conditioned to seal against the shoulder; and spring means biasing the seal member toward the shoulder.

  20. Indispensable tool

    SciTech Connect

    Robinson, Arthur

    2001-08-10

    Synchrotron radiation has become an indispensable research tool for a growing number of scientists in a seemingly ever expanding number of disciplines. We can thank the European Synchrotron Research Facility (ESRF) in Grenoble for taking an innovative step toward achieving the educational goal of explaining the nature and benefits of synchrotron radiation to audiences ranging from the general public (including students) to government officials to scientists who may be unfamiliar with x-ray techniques and synchrotron radiation. ESRF is the driving force behind a new CD-ROM playable on both PCs and Macs titled Synchrotron light to explore matter. Published by Springer-Verlag, the CD contains both English and French versions of a comprehensive overview of the subject.

  1. Optical Tools

    NASA Astrophysics Data System (ADS)

    Roncali, E.; Tavitian, B.; Texier, I. E.; Peltié, P.; Perraut, F.; Boutet, J.; Cognet, L.; Lounis, B.; Marguet, D.; Thoumine, O.; Tramier, M.

    Fluorescence is a physical phenomenon described for the first time in 1852 by the British scientist George G. Stokes, famous for his work in mathematics and hydrodynamics. He observed the light emitted by a mineral after excitation (absorption of light by the mineral) by UV light. He then formulated what has become known as Stokes’ law, which says that the wavelength of fluorescence emission is longer than the excitation wavelength used to generate it. Some phenomena departing from this rule were later discovered, but do not in fact invalidate it. The possibility of visible excitation was subsequently developed, with the discovery of many fluorescing aromaticmolecules, called fluorophores. The identification of these compounds and improved control over the physical phenomenon meant that by 1930 research tools had been developed in biology, e.g., labeling certain tissues and bacteria so as to observe them by fluorescence. The optical microscope as it had existed since the nineteenth century thus gave rise to the fluorescence microscope: a reflection system to supply the light required to excite the fluorophores was added to the standard microscope, together with a suitable filtering system. Fluorescence microscopy soon became an important tool for biological analysis both in vitro and ex vivo, and other applications of light emission were also devised (light-emission phenomena of which fluorescence is a special case, described further in Sect. 7.2). It became possible to study phenomena that could not be observed by standard optical microscopy. Among other things, the location of molecules inside cells, monitoring of intracellular processes, and detection of single molecules all become feasible by means of fluorescence microscopy.

  2. [Radioactivity monitoring of steel processing in Croatian steel mills and foundries].

    PubMed

    Sofilić, Tahir; Marjanović, Tihana; Rastovcan-Mioc, Alenka

    2006-03-01

    The last twenty years have seen a number of cases of radioactive pollution in metallurgical industry. Therefore many metal producers have implemented systematic monitoring of radioactivity in their production processes, especially in steel processing, steel being the most applied construction material with the annual world output of over billion tonnes. Learning from the experience of the best known steel producers in Europe and the world Croatian steel mills have introduced radioactivity surveillance and control systems for radioactive elements in steel scrap, semi-finished and finished products. This paper argues in favour of radioactivity surveillance and control systems in steel and steel castings production in Croatia, and describes current systems and solutions available. Since we lack our own standards and regulations to control both domestic and imported steel scrap, semi-finished products (crude steel, hot and cold rolled strip) and finished products, we need to start implementing radioactivity surveillance and control systems in our steel and steel castings production applying the current international recommendations and guidelines, until we build up our own monitoring system and adopt legislation on the national level. This paper gives an overview of the basic types of radioactivity surveillance and control systems, the most frequent requirements to be met, as well as of the measurement and information flow in their application in steel and steel castings production.

  3. Investigation on the Surface Integrity and Tool Wear in Cryogenic Machining

    SciTech Connect

    Dutra Xavier, Sandro E.; Delijaicov, Sergio; Farias, Adalto de; Stipkovic Filho, Marco; Ferreira Batalha, Gilmar

    2011-01-17

    This work aimed to study the influences of cryogenic cooling on tool wear, comparing it to dry machining during on the surface integrity of test circular steel SAE 52100 hardened to 62 HRC, during the turning of the face, with the use of special PcBN, using liquid nitrogen with cooler. The surface integrity parameters analyzed were: surface roughness and white layer and tool wear. The results of the present work indicated reduction in tool wear, which enhance the tool life.

  4. Bactericidal activity of copper and niobium-alloyed austenitic stainless steel.

    PubMed

    Baena, M I; Márquez, M C; Matres, V; Botella, J; Ventosa, A

    2006-12-01

    Biofouling and microbiologically influenced corrosion are processes of material deterioration that originate from the attachment of microorganisms as quickly as the material is immersed in a nonsterile environment. Stainless steels, despite their wide use in different industries and as appliances and implant materials, do not possess inherent antimicrobial properties. Changes in hygiene legislation and increased public awareness of product quality makes it necessary to devise control methods that inhibit biofilm formation or to act at an early stage of the biofouling process and provide the release of antimicrobial compounds on a sustainable basis and at effective level. These antibacterial stainless steels may find a wide range of applications in fields, such as kitchen appliances, medical equipment, home electronics, and tools and hardware. The purpose of this study was to obtain antibacterial stainless steel and thus mitigate the microbial colonization and bacterial infection. Copper is known as an antibacterial agent; in contrast, niobium has been demonstrated to improve the antimicrobial effect of copper by stimulating the formation of precipitated copper particles and its distribution in the matrix of the stainless steel. Thus, we obtained slides of 3.8% copper and 0.1% niobium alloyed stainless steel; subjected them to three different heat treatment protocols (550 degrees C, 700 degrees C, and 800 degrees C for 100, 200, 300, and 400 hours); and determined their antimicrobial activities by using different initial bacterial cell densities and suspending solutions to apply the bacteria to the stainless steels. The bacterial strain used in these experiments was Escherichia coli CCM 4517. The best antimicrobial effects were observed in the slides of stainless steel treated at 700 degrees C and 800 degrees C using an initial cell density of approximately 10(5) cells ml(-1) and phosphate-buffered saline as the solution in which the bacteria came into contact with

  5. Steel-cased wells in 3-D controlled source EM modelling

    NASA Astrophysics Data System (ADS)

    Patzer, Cedric; Tietze, Kristina; Ritter, Oliver

    2017-05-01

    Over the last decades, electromagnetic methods have become an accepted tool for a wide range of geophysical exploration purposes and nowadays even for monitoring. Application to hydrocarbon monitoring, for example for enhanced oil recovery, is hampered by steel-cased wells, which typically exist in large numbers in producing oil fields and which distort electromagnetic fields in the subsurface. Steel casings have complex geometries as they are very thin but vertically extended; moreover, the conductivity contrast of steel to natural materials is in the range of six orders of magnitude. It is therefore computationally prohibitively costly to include such structures directly into the modelling grid, even for finite element methods. To tackle the problem we developed a method to describe steel-cased wells as series of substitute dipole sources, which effectively interact with the primary field. The new approach cannot only handle a single steel-cased well, but also an arbitrary number, and their interaction with each other. We illustrate the metal casing effect with synthetic 3-D modelling of land-based controlled source electromagnetic data. Steel casings distort electromagnetic fields even for large borehole-transmitter distances above 2 km. The effect depends not only on the distance between casing and transmitter, but also on the orientation of the transmitter to the borehole. Finally, we demonstrate how the presence of steel-cased wells can be exploited to increase the sensitivity and enhance resolution in the target region. Our results show that it is at least advisable to consider the distribution of steel-cased wells already at the planning phase of a controlled source electromagnetic field campaign.

  6. Microstructural characterisation of friction stir welding joints of mild steel to Ni-based alloy 625

    SciTech Connect

    Rodriguez, J.; Ramirez, A.J.

    2015-12-15

    In this study, 6-mm-thick mild steel and Ni-based alloy 625 plates were friction stir welded using a tool rotational speed of 300 rpm and a travel speed of 100 mm·min{sup −1}. A microstructural characterisation of the dissimilar butt joint was performed using optical microscopy, scanning and transmission electron microscopy, and energy dispersive X-ray spectroscopy (XEDS). Six different weld zones were found. In the steel, the heat-affected zone (HAZ) was divided into three zones and was composed of ferrite, pearlite colonies with different morphologies, degenerated regions of pearlite and allotriomorphic and Widmanstätten ferrite. The stir zone (SZ) of the steel showed a coarse microstructure consisting of allotriomorphic and Widmanstätten ferrite, degenerate pearlite and MA constituents. In the Ni-based alloy 625, the thermo-mechanically affected zone (TMAZ) showed deformed grains and redistribution of precipitates. In the SZ, the high deformation and temperature produced a recrystallised microstructure, as well as fracture and redistribution of MC precipitates. The M{sub 23}C{sub 6} precipitates, present in the base material, were also redistributed in the stir zone of the Ni-based alloy. TMAZ in the steel and HAZ in the Ni-based alloy could not be identified. The main restorative mechanisms were discontinuous dynamic recrystallisation in the steel, and discontinuous and continuous dynamic recrystallisation in the Ni-based alloy. The interface region between the steel and the Ni-based alloy showed a fcc microstructure with NbC carbides and an average length of 2.0 μm. - Highlights: • Comprehensive microstructural characterisation of dissimilar joints of mild steel to Ni-based alloy • Friction stir welding of joints of mild steel to Ni-based alloy 625 produces sound welds. • The interface region showed deformed and recrystallised fcc grains with NbC carbides and a length of 2.0 μm.

  7. Microstructure and Mechanical Properties of HSLA-100 Steel

    DTIC Science & Technology

    1990-12-01

    13 Figure 4. High Strength Bainite Strength Components .................... 20 Figure 5. Bainitic Steel Tempering and DBTT ...21 Figure 6. Tempered Bainite Steel Yield Stress and DBTT .................. 21 Figure 7. HSLA-100 Steel Yield Strength versus Aging...Energy at -84°C ............... 31 Figure 14. HSLA-100 Steel Lot GQH DBTT ............................ 31 Figure 15. HSLA-100 Steel Lot GQH Ductility

  8. Bond characteristics of steel fiber and deformed reinforcing steel bar embedded in steel fiber reinforced self-compacting concrete (SFRSCC)

    NASA Astrophysics Data System (ADS)

    Aslani, Farhad; Nejadi, Shami

    2012-09-01

    Steel fiber reinforced self-compacting concrete (SFRSCC) is a relatively new composite material which congregates the benefits of the self-compacting concrete (SCC) technology with the profits derived from the fiber addition to a brittle cementitious matrix. Steel fibers improve many of the properties of SCC elements including tensile strength, ductility, toughness, energy absorption capacity, fracture toughness and cracking. Although the available research regarding the influence of steel fibers on the properties of SFRSCC is limited, this paper investigates the bond characteristics between steel fiber and SCC firstly. Based on the available experimental results, the current analytical steel fiber pullout model (Dubey 1999) is modified by considering the different SCC properties and different fiber types (smooth, hooked) and inclination. In order to take into account the effect of fiber inclination in the pullout model, apparent shear strengths (τ (app)) and slip coefficient (β) are incorporated to express the variation of pullout peak load and the augmentation of peak slip as the inclined angle increases. These variables are expressed as functions of the inclined angle (ϕ). Furthurmore, steel-concrete composite floors, reinforced concrete floors supported by columns or walls and floors on an elastic foundations belong to the category of structural elements in which the conventional steel reinforcement can be partially replaced by the use of steel fibers. When discussing deformation capacity of structural elements or civil engineering structures manufactured using SFRSCC, one must be able to describe thoroughly both the behavior of the concrete matrix reinforced with steel fibers and the interaction between this composite matrix and discrete steel reinforcement of the conventional type. However, even though the knowledge on bond behavior is essential for evaluating the overall behavior of structural components containing reinforcement and steel fibers

  9. Bond characteristics of steel fiber and deformed reinforcing steel bar embedded in steel fiber reinforced self-compacting concrete (SFRSCC)

    NASA Astrophysics Data System (ADS)

    Aslani, Farhad; Nejadi, Shami

    2012-09-01

    Steel fiber reinforced self-compacting concrete (SFRSCC) is a relatively new composite material which congregates the benefits of the self-compacting concrete (SCC) technology with the profits derived from the fiber addition to a brittle cementitious matrix. Steel fibers improve many of the properties of SCC elements including tensile strength, ductility, toughness, energy absorption capacity, fracture toughness and cracking. Although the available research regarding the influence of steel fibers on the properties of SFRSCC is limited, this paper investigates the bond characteristics between steel fiber and SCC firstly. Based on the available experimental results, the current analytical steel fiber pullout model (Dubey 1999) is modified by considering the different SCC properties and different fiber types (smooth, hooked) and inclination. In order to take into account the effect of fiber inclination in the pullout model, apparent shear strengths ( τ ( app)) and slip coefficient ( β) are incorporated to express the variation of pullout peak load and the augmentation of peak slip as the inclined angle increases. These variables are expressed as functions of the inclined angle ( ϕ). Furthurmore, steel-concrete composite floors, reinforced concrete floors supported by columns or walls and floors on an elastic foundations belong to the category of structural elements in which the conventional steel reinforcement can be partially replaced by the use of steel fibers. When discussing deformation capacity of structural elements or civil engineering structures manufactured using SFRSCC, one must be able to describe thoroughly both the behavior of the concrete matrix reinforced with steel fibers and the interaction between this composite matrix and discrete steel reinforcement of the conventional type. However, even though the knowledge on bond behavior is essential for evaluating the overall behavior of structural components containing reinforcement and steel fibers

  10. Accelerated carbonation of steel slags in a landfill cover construction

    SciTech Connect

    Diener, S.; Andreas, L.; Herrmann, I.; Ecke, H.; Lagerkvist, A.

    2010-01-15

    Steel slags from high-alloyed tool steel production were used in a full scale cover construction of a municipal solid waste (MSW) landfill. In order to study the long-term stability of the steel slags within the final cover, a laboratory experiment was performed. The effect on the ageing process, due to i.e. carbonation, exerted by five different factors resembling both the material characteristics and the environmental conditions is investigated. Leaching behaviour, acid neutralization capacity and mineralogy (evaluated by means of X-ray diffraction, XRD, and thermogravimetry/differential thermal analysis, TG/DTA) are tested after different periods of ageing under different conditions. Samples aged for 3 and 10 months were evaluated in this paper. Multivariate data analysis was used for data evaluation. The results indicate that among the investigated factors, ageing time and carbon dioxide content of the atmosphere were able to exert the most relevant effect. However, further investigations are required in order to clarify the role of the temperature.

  11. Effect of Machining Parameters on Oxidation Behavior of Mild Steel

    NASA Astrophysics Data System (ADS)

    Majumdar, P.; Shekhar, S.; Mondal, K.

    2015-01-01

    This study aims to find out a correlation between machining parameters, resultant microstructure, and isothermal oxidation behavior of lathe-machined mild steel in the temperature range of 660-710 °C. The tool rake angles "α" used were +20°, 0°, and -20°, and cutting speeds used were 41, 232, and 541 mm/s. Under isothermal conditions, non-machined and machined mild steel samples follow parabolic oxidation kinetics with activation energy of 181 and ~400 kJ/mol, respectively. Exaggerated grain growth of the machined surface was observed, whereas, the center part of the machined sample showed minimal grain growth during oxidation at higher temperatures. Grain growth on the surface was attributed to the reduction of strain energy at high temperature oxidation, which was accumulated on the sub-region of the machined surface during machining. It was also observed that characteristic surface oxide controlled the oxidation behavior of the machined samples. This study clearly demonstrates the effect of equivalent strain, roughness, and grain size due to machining, and subsequent grain growth on the oxidation behavior of the mild steel.

  12. Direct diamond turning of steel molds for optical replication

    NASA Astrophysics Data System (ADS)

    Klocke, Fritz; Dambon, Olaf; Bulla, Benjamin; Heselhaus, Michael

    2009-05-01

    In this paper the most recent investigations in ultrasonic assisted diamond machining of hardened steel at the Fraunhofer IPT is presented. The goal of this technology is to unify the outrageous specifications of diamond machining process with steel material. The focus lies on the kinematic influence of the discrete frequencies 40 kHz and 60 kHz. Special interest is given to the reachable surface roughness depending on process parameters. The machined steel (1.2083, X40Cr14, STAVAX ESU) is a common mold die material for optical replication processes.Results of the accomplished investigations show the potential of the ultrasonic assisted process and recent developments. By increasing the frequency from 40 kHz to 60 kHz the overall process stability is increased. This makes the process less vulnerable towards feed rate variation or towards the variation of machined material hardness. Furthermore no tool wear is detected at high material removal rates or high cutting distances during component machining.

  13. A mortality study among mild steel and stainless steel welders.

    PubMed Central

    Moulin, J J; Wild, P; Haguenoer, J M; Faucon, D; De Gaudemaris, R; Mur, J M; Mereau, M; Gary, Y; Toamain, J P; Birembaut, Y

    1993-01-01

    A mortality study was carried out in conjunction with the European mortality study among welders coordinated by the International Agency for Research on Cancer (IARC). The study was aimed at assessing risks for lung cancer in relation to exposure to asbestos, welding fumes containing chromium and nickel, and tobacco smoke. The study included a cohort of 2721 welders and an internal comparison group of 6683 manual workers employed in 13 factories in France. The mortality of the two cohorts was studied from 1975 to 1988 by the historical prospective method. Job histories of welders were traced including welding processes used, metals welded, and proportion of worktime spent in welding. Data on smoking habits were collected from medical records. The observed number of deaths were compared with those expected (standardised mortality ratio (SMR)) based on national rates with adjustments for age, sex, and calendar time. The smoking habits of 87% of the whole study population were known. The distribution of welders and controls according to smoking was not statistically different. The overall mortality was slightly higher for welders (SMR = 1.02, 95% confidence interval (95% CI) 0.89-1.18) than for controls (SMR = 0.91, 95% CI 0.84-0.99). For lung cancer, the SMR was 1.24 (95% CI 0.75-1.94) for welders, whereas the corresponding value was lower for controls (SMR = 0.94, 95% CI 0.68-1.26). The SMR for lung cancer was 1.59 among non-shipyard mild steel welders (95% CI 0.73-3.02). This contrasted with the results for all stainless steel welders (SMR = 0.92, 95% CI 0.19-2.69), and for stainless steel welders predominantly exposed to chromium VI (SMR = 1.03, 95% CI 0.12-3.71). Moreover, SMRs for lung cancer for mild steel welders tended to increase with duration of exposure and time since first exposure, leading to significant excesses for duration > or = 20 years and latency > or = 20 years. Such a pattern was not found for stainless steel welders. PMID:8457490

  14. Niobium in Microalloyed Rail Steels

    NASA Astrophysics Data System (ADS)

    Ray, A.; Bhadeshia, H. K. D. H.

    Rails generally do not have a homogeneous austenite grain structure across their sections because the degree of plastic strain achieved during hot-rolling depends on location. Here we explore a philosophy in which niobium microalloying may be introduced in order to thermomechanically process the material so that pancaked and refined austenite grains may eventually be achieved in the critical regions of the rail. The essential principle in alloy design involves the avoidance of coarse niobium carbide precipitates in the regions of the steel that contain chemical segregation caused by non-equilibrium solidification. Both pearlitic and cementite-free bainitic rails have been studied. The work is of generic value to the design of high-carbon microalloyed steels.

  15. Longer Life for Steel Structures

    NASA Technical Reports Server (NTRS)

    1990-01-01

    IC 531 is a coating manufactured and marketed by Inorganic Coatings, Inc. The coating was developed by Goddard to protect structures at Kennedy Space Center. It is a high ratio potassium silicate formula. The coating is water based, nontoxic, and nonflammable. It generates no volatile organic compounds nor hazardous chemical waste, and bonds to steel in 30 minutes. At the present time, no one can say for sure how long IC 531's effective lifetime is. Some of the original Goddard test applications of 1976 are still going strong after lengthy exposure to the Sun, salt and moisture. Says IC in company literature: 'IC 531 offers virtually permanent protection for steel. We predict it will protect structures for well beyond 25 years. If necessary, it is infinitely maintainable; if damaged, it can easily be touched up with more IC 531.'

  16. Light microscopy of carbon steels

    SciTech Connect

    Samuels, L.E.

    1998-12-31

    Containing over 1,200 representative micrographs and the information and explanatory text that makes them really useful: composition, condition, etchant, and magnification, and more than 100 graphs and tables, this how to book not only gives everyday working examples, but also discusses the relationship between the constitution, metallurgy, and microstructure of various carbon steel products. Written by a renowned expert in metallography, this definitive work is a must for all those working in this area. Contents include: nomenclature of phases and constituents; phase transformations; low-carbon irons and steels; annealing and normalizing; spheroidization and graphitization; austenitization; transformation of austenite; tempering of martensite; welding; surface oxidation, decarburation; and oxidation scaling; glossary of terms; etching methods; conversion tables.

  17. Underwater wet welding of steel

    SciTech Connect

    Ibarra, S.; Liu, S.; Olson, D.L.

    1995-05-01

    Underwater wet welding is conducted directly in water with the shielded metal arc (SMA) and flux cored arc (FCA) welding processes. Underwater wet welding has been demonstrated as an acceptable repair technique down to 100 meters (325 ft.) in depth, but wet welds have been attempted on carbon steel structures down to 200 meters (650 ft.). The primary purpose of this interpretive report is to document and evaluate current understanding of metallurgical behavior of underwater wet welds so that new welding consumables can be designed and new welding practices can be developed for fabrication and repair of high strength steel structures at greater depths. First the pyrometallurgical and physical metallurgy behaviors of underwater weldments are discussed. Second, modifications of the welding consumables and processes are suggested to enhance the ability to apply wet welding techniques.

  18. Steel Industry Energy Bandwidth Study

    SciTech Connect

    none,

    2004-10-01

    ITP conducted a study on energy use and potential savings, or "bandwidth" study, in major steelmaking processes. Intended to provide a realistic estimate of the potential amount of energy that can be saved in an industrial process, the "bandwidth" refers to the difference between the amount of energy that would be consumed in a process using commercially available technology versus the minimum amount of energy needed to achieve those same results based on the 2nd law of thermodynamics. The Steel Industry Energy Bandwidth Study (PDF 133 KB) also estimates steel industry energy use in the year 2010, and uses that value as a basis for comparison against the minimum requirements. This energy savings opportunity for 2010 will aid focus on longer term R&D.

  19. Existing Steel Railway Bridges Evaluation

    NASA Astrophysics Data System (ADS)

    Vičan, Josef; Gocál, Jozef; Odrobiňák, Jaroslav; Koteš, Peter

    2016-12-01

    The article describes general principles and basis of evaluation of existing railway bridges based on the concept of load-carrying capacity determination. Compared to the design of a new bridge, the modified reliability level for existing bridges evaluation should be considered due to implementation of the additional data related to bridge condition and behaviour obtained from regular inspections. Based on those data respecting the bridge remaining lifetime, a modification of partial safety factors for actions and materials could be respected in the bridge evaluation process. A great attention is also paid to the specific problems of determination of load-caring capacity of steel railway bridges in service. Recommendation for global analysis and methodology for existing steel bridge superstructure load-carrying capacity determination are described too.

  20. Welding of high chromium steels

    NASA Technical Reports Server (NTRS)

    Miller, W B

    1928-01-01

    A brief description is given of different groups of high chromium steels (rustless iron and stainless steels) according to their composition and more generally accepted names. The welding procedure for a given group will be much the same regardless of the slight variations in chemical composition which may exist within a certain group. Information is given for the tensile properties (yield point and ultimate strength) of metal sheets and welds before and after annealing on coupons one and one-half inches wide. Since welds in rustless iron containing 16 to 18 percent chromium and 7 to 12 percent nickel show the best combination of strength and ductility in the 'as welded' or annealed condition, it is considered the best alloy to use for welded construction.

  1. Residual stresses and microstructure of H13 steel formed by combining two different direct fabrication methods

    SciTech Connect

    Maziasz, P.J.; Payzant, E.A.; Schlienger, M.E.; McHugh, K.M.

    1998-10-13

    Direct fabrication (DF) of tool and die steels by rapid solidification techniques can produce near-net-shape parts and components with unique properties, and without the distortions caused by conventional normalizing and tempering heat-treatments. When combined with sophisticated 3-dimensional computer control to build complex solid metallic shapes, one has the capability of using DF for rapid prototyping. Spray forming using a circular converging/diverging atomizer is a DF process being developed at the Idaho National Engineering and Environmental Laboratory (INEEL) for rapid manufacturing of tool and die steels like H-13. Laser Engineered Net Shaping (LENS{trademark}) is a DF process being developed at Sandia National laboratory (SNL). LENS involves laser-processing fine powder metal sprays into complex, fully-dense 3-dimensional shapes with fine-detail control that would allow rapid prototyping of tools or dies. One logical combination of the two processes is to combine spray forming to replicate most of the die surface and backing, and then t o build other die-surface fine-features with LENS. Premium H-13 steel was used because it belongs to the widely used group of hot-work steels that have good resistance to heat, pressure and abrasion for metal-forging and aluminum die-casting applications. The microstructure and residual stresses that exist across the interface of a composite metal produced by these two DF methods are critical parameters in producing crack-free components with functional properties. The purpose of this work is to combine unique neutron-diffraction facilities at the Oak Ridge National Laboratory (ORNL) for measuring bulk residual stresses with these two different DF processes to characterize LENS deposits of H-13 steel made on a spray-formed base of that same steel.

  2. Inductive resistivity logging in steel-cased boreholes. SBIR Phase 2 progress report

    SciTech Connect

    Wilt, M.

    1999-07-01

    SBIR Phase 2 project 40145-97-I calls for the design and construction of a prototype inductive logging device to measure formation resistivity from within a steel-cased borehole. The SCIL (Steel Casing Induction Logger) tool is intended for reservoir characterization and process monitoring in an oil field environment. This report summarizes findings from the initial project period. In this phase, bench model measurements were made to test casing compensation schemes, numerical models were calculated to optimize the tool configuration and associated formation sensitivity and the preliminary design of the tool was completed. The bench tests constitute fundamental research on determining the characteristics of steel well casing and on developing means of separating the effects of the casing and the formation. This technology is crucial to the success of the project and significant progress has been made towards the goal of recovering the formation resistivity from inside the casing. Next, a series of sensitivity and tool configuration studies have been completed through partner Dr. David Alumbaugh at Sandia National Laboratories. These numerical results help to optimize the tool configuration and allow one to calculate the expected formation sensitivity. These models are preliminary to data interpretation software to be developed in the next project period. The initial hardware design of the tool has been completed, and ordering parts has begun for later manufacture and assembly. The tool, which is designed for maximum flexibility of deployment, will have a powerful transmitter, an array of three component sensors and sufficient dynamic range to operate in standard oil field steel-cased boreholes.

  3. Effect of Cryogenic Treatment on Tool Life of HSS Tool (S400) and Surface Finish of the Material in Turning of SS304

    NASA Astrophysics Data System (ADS)

    Pradeep, A. V.; Prasad, S. V. Satya; Suryam, L. V.; Kesava Rao, Y.; Kesava, D.

    2016-09-01

    Tool steels are the most widely used components for the single point cutting tool in the turning process. Therefore the characterization of the properties of these tool materials has a great significance when turning is carried out. Alteration and improvement of the properties of these tool steels will enhance the machining process. The present work explores the effect of cryogenic treatment done on a single point cutting tool (HSS) which helps in machining different tool materials with a better surface finish and increased tool life. Turning operation is done on commercial grade material SS304 by using both cryogenically treated and non-treated HSS tool bits at three different speeds (180, 300 & 530 rpm) with the time interval of 3 minutes until the nose fracture is observed. The graphs were plotted between the tool wear and time interval for each speed comparing both the tool lives and it is found that the cryogenically treated tool has sustained for more time than non-cryogenically treated tool at any given speeds standing with more tool life. Also the forces generated during the operation were observed by tool force dynamometer and found to be more in NTT than CTT and even the surface finish of the work piece got enhanced when CT tool is used at any given speeds.

  4. Nano-composite stainless steel

    DOEpatents

    Dehoff, Ryan R.; Blue, Craig A.; Peter, William H.; Chen, Wei; Aprigliano, Louis F.

    2015-07-14

    A composite stainless steel composition is composed essentially of, in terms of wt. % ranges: 25 to 28 Cr; 11 to 13 Ni; 7 to 8 W; 3.5 to 4 Mo; 3 to 3.5 B; 2 to 2.5 Mn; 1 to 1.5 Si; 0.3 to 1.7 C; up to 2 O; balance Fe. The composition has an austenitic matrix phase and a particulate, crystalline dispersed phase.

  5. Steel Industry Marginal Opportunity Analysis

    SciTech Connect

    none,

    2005-09-01

    The Steel Industry Marginal Opportunity Analysis (PDF 347 KB) identifies opportunities for developing advanced technologies and estimates both the necessary funding and the potential payoff. This analysis determines what portion of the energy bandwidth can be captured through the adoption of state-of-the-art technology and practices. R&D opportunities for addressing the remainder of the bandwidth are characterized and plotted on a marginal opportunity curve.

  6. Powder Processing of Trip Steel

    DTIC Science & Technology

    1977-04-01

    60, 1967, p. 252-259. 2. AZRIN, M ., OLSON, G. B., and GAGNE, R. A. Inhomogeneous Deformation and Strain-Rate Effects in High-Strength TRIP Steels...Mat. Sci. Eng., v. 23, May 1976, p. 33^1. 3. ANTOLOVICH , S. D., and SINGH, B. On the Toughness Increment Associated with the Austenite to Martensite...1 ATTN: SCCR-2 Naval Research Laboratory, Washington, D. C. 20375 1 ATTN: Dr. J. M . Krafft - Code 8430 Chief of Naval Research, Arlington

  7. A study of Damascus steel

    SciTech Connect

    Berge, P.

    1995-02-16

    The Damascus sword has been an article of fascination for many years to blade collectors and metallurgists alike. The blades were given their name by Europeans who encountered these blades which originated from Damascus, Syria. They are best known for the appearance of the blade face. Genuine Damascus blades show swirling patterns of alternating light and dark regions which are due to the microstructure of the steel. The microstructure consists of arrays of well rounded cementite patterns in a matrix of either pearlite, bainite, or martensite. When this structure is etched the matrix will turn dark leaving the cementite particles light. Although many blades were produced over the centuries, while some of the process is known the making of a genuine Damascus blade today is generally considered a lost art. Many scientists have studied the subject in an attempt to understand the complex process by which the clustered arrays of cementite particles develop in the steel blades. The most prominent theories to date are presented in the General Introduction to this thesis. The thesis is divided into four main parts. In the first part, four proposed mechanisms of cementite cluster sheet formation as they relate to the banding theory are introduced. Experiments to investigate these mechanisms are presented. In Part II, collaborative research focused on the methodology of the reconstructed process for making Damascus steel is presented. In the third part, a study into the graphitization of the reconstructed blades is presented. In Part IV, experimental attempts at producing Damascus steel ingots in the laboratory are presented.

  8. Preparation and characterization of 304 stainless steel/Q235 carbon steel composite material

    NASA Astrophysics Data System (ADS)

    Shen, Wenning; Feng, Lajun; Feng, Hui; Cao, Ying; Liu, Lei; Cao, Mo; Ge, Yanfeng

    The composite material of 304 stainless steel reinforced Q235 carbon steel has been prepared by modified hot-rolling process. The resulted material was characterized by scanning electron microscope, three-electrode method, fault current impact method, electrochemical potentiodynamic polarization curve measurement and electrochemical impedance spectroscopy. The results showed that metallurgical bond between the stainless steel layer and carbon steel substrate has been formed. The composite material exhibited good electrical conductivity and thermal stability. The average grounding resistance of the composite material was about 13/20 of dip galvanized steel. There has no surface crack and bubbling formed after fault current impact. The composite material led to a significant decrease in the corrosion current density in soil solution, compared with that of hot dip galvanized steel and bare carbon steel. On the basis polarization curve and EIS analyses, it can be concluded that the composite material showed improved anti-corrosion property than hot-dip galvanized steel.

  9. Effect of Zinc Coatings on Joint Properties and Interfacial Reactions in Aluminum to Steel Ultrasonic Spot Welding

    NASA Astrophysics Data System (ADS)

    Haddadi, F.; Strong, D.; Prangnell, P. B.

    2012-03-01

    Dissimilar joining of aluminum to steel sheet in multimaterial automotive structures is an important potential application of ultrasonic spot welding (USW). Here, the weldability of different zinc-coated steels with aluminum is discussed, using a 2.5-kW USW welder. Results show that soft hot-dipped zinc (DX56-Z)-coated steel results in better weld performance than hard (galv-annealed) zinc coatings (DX53-ZF). For Al to hard galv-annealed-coated steel welds, lap shear strengths reached a maximum of ~80% of the strength of an Al-Al joint after a 1.0 s welding time. In comparison, welds between Al6111-T4 and hot dipped soft zinc-coated steel took longer to achieve the same maximum strength, but nearly matched the Al-Al joint properties. The reasons for these different behaviors are discussed in terms of the interfacial reactions between the weld members.

  10. 77 FR 67400 - RG Steel Wheeling, LLC, a Division of RG Steel, LLC, Doing Business as Wheeling Corrugating...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-09

    ... Employment and Training Administration RG Steel Wheeling, LLC, a Division of RG Steel, LLC, Doing Business as..., 2012, applicable to workers of RG Steel Wheeling, LLC, a division of RG Steel, LLC, doing business as... RG Steel, LLC, doing business as Wheeling Corrugating Company, Beech Bottom, West Virginia,...

  11. Utilization of structural steel in buildings.

    PubMed

    Moynihan, Muiris C; Allwood, Julian M

    2014-08-08

    Over one-quarter of steel produced annually is used in the construction of buildings. Making this steel causes carbon dioxide emissions, which climate change experts recommend be reduced by half in the next 37 years. One option to achieve this is to design and build more efficiently, still delivering the same service from buildings but using less steel to do so. To estimate how much steel could be saved from this option, 23 steel-framed building designs are studied, sourced from leading UK engineering firms. The utilization of each beam is found and buildings are analysed to find patterns. The results for over 10 000 beams show that average utilization is below 50% of their capacity. The primary reason for this low value is 'rationalization'-providing extra material to reduce labour costs. By designing for minimum material rather than minimum cost, steel use in buildings could be drastically reduced, leading to an equivalent reduction in 'embodied' carbon emissions.

  12. Short-term hot hardness characteristics of rolling-element steels

    NASA Technical Reports Server (NTRS)

    Chevalier, J. L.; Dietrich, M. W.; Zaretsky, E. V.

    1972-01-01

    Short-term hot hardness studies were performed with five vacuum-melted steels at temperatures from 294 to 887 K (70 to 1140 F). Based upon a minimum Rockwell C hardness of 58, the temperature limitation on all materials studied was dependent on the initial room temperature hardness and the tempering temperature of each material. For the same room temperature hardness, the short-term hot hardness characteristics were identical and independent of material composition. An equation was developed to predict the short-term hardness at temperature as a function of initial room temperature hardness for AISI 52100, as well as the high-speed tool steels.

  13. RESIDUAL STRESS IN HARDENED STEEL CYLINDERS

    DTIC Science & Technology

    ultimate strength of the steel and in some instances caused cracking, and (4) stress patterns of interrupted quench specimens were not consistent enough to warrant a conclusion. (Author)...A study was conducted to (1) measure residual stress in hardened steel solid cylinders, (2) correlate the stress values with heat treatments, and (3...develop a dissolution technique. Residual stress patterns for 12 solid cylinders of 4160 steel, heat treated by various methods, were determined

  14. Cadmium Alternatives for High-Strength Steel

    DTIC Science & Technology

    2011-09-22

    FINAL REPORT Cadmium Alternatives for High-Strength Steel WP-200022 Steven A. Brown Naval Air Warfare Center Aircraft Division Patuxent...ESTCP WP-0022 Final Report “Cadmium Alternatives for High-Strength Steel ” 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Steven...SUPPLEMENTARY NOTES 14. ABSTRACT Testing was conducted for cadmium alternative coating systems IAW the “High Strength Steel Joint Test Protocol for

  15. Evaluation of the Benefits of HSLA Steels

    DTIC Science & Technology

    1989-03-01

    quenched and tempered steels , such as HY80 and HY1OO, require preheat and interpass temperature controls during welding of plates thicker than 1/2 inch...interpass tempera- tures and heat input limitations. Strict adherence to these requirements is mandatory to avoid cracking in hydrogen- sensitive steels ...requirement and excellent weldability of this steel will probably lower produc- tion costs and cracking -related repairs enough to overcome the slight

  16. Solidification Based Grain Refinement in Steels

    DTIC Science & Technology

    2011-09-27

    Please complete the Award Information section below so that technical information can be related to a specific award. Please save the file using the...Technology, Vol. 21, No. 3, pp. 325-333, 2005. 4. Peter. J., Peaslee, K. D.. and Panda , D. "Thermomechanical processing of HSLA wide-flange steel beams...niobium precipitates in HSLA steel". Steel Research International, Vol. 75, No. 1 Lpp. 753-758. 2004. 20. Peter, Joerg; Peaslee, Kent D.; Panda Dhiren

  17. Recycling steel. Conducting a waste audit.

    PubMed

    Crawford, G

    1996-01-01

    This is the second in a series of three articles regarding steel can recycling from foodservice operations of healthcare facilities. This article highlights the basic methods of recycling steel cans, and includes information on conducting a waste audit and negotiating with a hauler regarding the benefits of recycling. The previous article discussed how steel is recycled across the country. The next article will convey a case history of actual foodservice recycling practice from a healthcare facility.

  18. Nonmetallic Inclusions in HSLA Steel Weldments

    DTIC Science & Technology

    1989-12-01

    lowering the DBTT . Nickel prevents the hot shortness phenomenon often observed in copper-bearing steels . Nickel is also an austenite stabilizer. By lowering... STEEL WELDMENTS by Brent A. Douglas December, 1989 Thesis Advisor Alan G. Fox Approved for public release; distribution is unlimited. 90 ,-. S...ACCESSION NO. II. TITLE (Incude Security Claw fication) Nonmetallic Inclusions In HSLA Steel Weldments IZ. PERSONAL AUTHOR(S) Douglas, Brent A. 138

  19. Long-term hot-hardness characteristics of five through-hardened bearing steels

    NASA Technical Reports Server (NTRS)

    Anderson, N. E.

    1978-01-01

    Five vacuum-melted bearing steels tempered to various room temperature hardnesses: AISI 52100 and the tool steels AISI M-1, AISI M-50, Halmo, and WB-49 were studied. Hardness measurements were taken on AISI 52100 at room temperature and at elevated temperatures after soaking it at temperatures to 478 K (400 F) for as long as 1000 hours. Hardness measurements were also taken on the tool steels after soaking them at temperatures to 700 K (800 F) for as long at 1000 hours. None of the tool steel tempered during soaking and AISI 52100 did not temper when soaked at 366 K (200 F) for 1000 hours. However, AISI 52100 that was initially hardened to room temperature hardness of 62.5 or 64.5 lost hardness during the first 500 hours of the 1000-hour soak tests at temperatures greater than 394 K (250 F), but it maintained its hardness during the final 500 hours of soaking. Similarly, AISI 52100 initially hardened to room temperature hardness of 60.5 lost hardness during the first 500 hours of the 1000-hour soaking at temperatures greater than 422 K (300 F), but it maintained its hardness during the final 500 hours of soaking.

  20. Angular dependence of magnetic properties of 2% silicon electrical steel

    NASA Astrophysics Data System (ADS)

    Emura, M.; de Campos, M. F.; Landgraf, F. J. G.; Teixeira, J. C.

    2001-05-01

    In this work, we studied the anisotropy of the magnetic properties of a 2% silicon steel. Permeability, core losses, remanence and coercivity were analyzed in Epstein strips cut at 0°, 15°, 30°, 45°, 60°, 75° and 90° from the rolling direction. Coercive force monotonically increased from 0° to 90°, accompanied with a remanence decrease. On the other hand, a minimum in B50 and B25 was observed between 45 o and 60 o. This behavior can be explained by the steel sheet crystallographic texture, that shows a strong (1 1 0) [0 0 1] component, which develops the best properties in rolling direction (0 0 1) and is worse at 54°, where <1 1 1> lies. Losses behavior is more complex.