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Discussion: ''toughness variations during the tempering of a plain carbon martensitic steel'' by J. E. King, R. F. Smith and J. F. Knott. Retained austenite and transgranular tempered martensite embrittlement

Description: Discussion is presented to substantiate, clarify and reinterpret some of the results of the above authors for the existence and origin of tempered martensite embrittlement (TME) in relation to retained austenite, with reference to the experimental steels worked at LBL for the past several years.
Date: June 1, 1977
Creator: Rao, B.V.N. & Thomas, G.
Partner: UNT Libraries Government Documents Department
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The collaborative program of research in engineering sciences

Description: Research programs in the following areas are briefly described: High-Temperature Gas-Particle Reactions; Mathematical Modelling of Plasma Systems; Metal Transfer in Gas Metal-Arc Welding; Multivariable Control of Gas Metal-Arc Welding; Synthesis of Heat and Work Integration Systems for Chemical Process Plants; Parity Simulation of Dynamic Processes; Fundamentals of Elastic-Plastic Fracture: Three-Dimensional and Mechanistic Modelling; and Comminution of Energy Materials. Publications from each … more
Date: August 1, 1989
Creator: White, D.C.
Partner: UNT Libraries Government Documents Department
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Integrity of PWR pressure vessels during overcooling accidents

Description: The reactor pressure vessel in a pressurized water reactor is normally subjected to temperatures and pressures that preclude propagation of sharp, crack-like defects that might exist in the wall of the vessel. However, there is a class of postulated accidents, referred to as overcooling accidents, that can subject the pressure vessel to severe thermal shock while the pressure is substantial. As a result of such accidents vessels containing high concentrations of copper and nickel, which enhance… more
Date: January 1, 1982
Creator: Cheverton, R.D.; Iskander, S.K. & Whitman, G.D.
Partner: UNT Libraries Government Documents Department
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Investigation of joining techniques for advanced austenitic alloys

Description: Modified Alloys 316 and 800H, designed for high temperature service, have been developed at Oak Ridge National Laboratory. Assessment of the weldability of the advanced austenitic alloys has been conducted at the University of Tennessee. Four aspects of weldability of the advanced austenitic alloys were included in the investigation.
Date: May 1, 1991
Creator: Lundin, C. D.; Qiao, C. Y. P.; Kikuchi, Y.; Shi, C. & Gill, T. P. S.
Partner: UNT Libraries Government Documents Department
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Milliwatt Generator Project

Description: This report covers progress on the Milliwatt Generator Project from April 1986 through March 1988. Activities included fuel processing and characterization, production of heat sources, fabrication of pressure-burst test units, compatibility studies, impact testing, and examination of surveillance units. The major task of the Los Alamos Milliwatt Generator Project is to fabricate MC2893A heat sources (4.0 W) for MC2730A radioisotope thermoelectric generators (RTGS) and MC3599 heat sources (4.5 W… more
Date: May 1, 1992
Creator: Latimer, T.W. & Rinehart, G.H.
Partner: UNT Libraries Government Documents Department
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Low strain diameter expansion of internally pressurized Zircaloy-4 tubing at high temperatures

Description: Tests of closed-end, internally pressurized, Zircaloy-4 tubing specimens were utilized to develop low strain creep characteristics as a function of time at temperatures in the range of 1475/sup 0/F to 2000/sup 0/F (802/sup 0/C to 1093/sup 0/C) and hoop stresses in the range of 250 to 2500 psi for use in loss-of-coolant accident (LOCA) analyses. The strain rate above the start of the alpha to beta phase transformation region, approximately 1490/sup 0/F (810/sup 0/C), was found to be sensitive to… more
Date: March 1978
Creator: White, L.S. & Busby, C.C.
Partner: UNT Libraries Government Documents Department
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The rate dependence of the saturation flow stress of Cu and 1100 Al

Description: The strain-rate dependence of the saturation flow stress of OFHC Cu and 1100 Al from 10{sup {minus}3}s{sup {minus}1} to nearly to 10{sup 12}s{sup {minus}1} is examined. The flow stress above 10{sup 9}s{sup {minus}1} is estimated using Wallace's theory of overdriven shocks in metals. A transition to the power-law behavior {Psi} {approximately} {tau}{sub s}{sup 5} occurs at a strain rate of order 10{sup 5}s{sup {minus}1}. 10 refs., 2 figs.
Date: January 1, 1991
Creator: Preston, D.L.; Tonks, D.L. & Wallace, D.C.
Partner: UNT Libraries Government Documents Department
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Thermal and electrical conductivities of high purity tantalum

Description: The electrical resistivity and thermal conductivity of three high purity tantalum samples have been measured as functions of temperature over a temperature range of 5K to 65K. Sample purities ranged up to a resistivity ratio of 1714. The highest purity sample had a residual resistivity of .76 x 10/sup -10/OMEGA-m. The intrinsic resistivity varied as T/sup 3/./sup 9/ from 10K to 31K. The thermal conductivity of the purest sample had a maximum of 840 W/mK at 9.8K. The intrinsic thermal resistivit… more
Date: January 1, 1978
Creator: Archer, S. L.
Partner: UNT Libraries Government Documents Department
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PNL technical review of pressurized thermal-shock issues. [PWR]

Description: Pacific Northwest Laboratory (PNL) was asked to develop and recommend a regulatory position that the Nuclear Regulatory Commission (NRC) should adopt regarding the ability of reactor pressure vessels to withstand the effects of pressurized thermal shock (PTS). Licensees of eight pressurized water reactors provided NRC with estimates of remaining effective full power years before corrective actions would be required to prevent an unsafe operating condition. PNL reviewed these responses and the r… more
Date: July 1, 1982
Creator: Pedersen, L. T.; Apley, W. J.; Bian, S. H.; Defferding, L. J.; Morgenstern, M. H.; Pelto, P. J. et al.
Partner: UNT Libraries Government Documents Department
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Evaluation of weldments in Type 21-6-9 stainless steel for Compact Ignition Tokamak structural applications: Phase 1

Description: Primary design considerations for the Compact Ignition Tokamak toroidal field-coil cases are yield strength and toughness in the temperature range from 77 to 300 K. Type 21-6-9 stainless steel, also still known by its original Armco Steel Company trade name Nitronic 40, is the proposed alloy for this application. It has high yield strength and usually adequate base metal toughness, but weldments in thick sections have not been adequately characterized in terms of mechanical properties or hot-cr… more
Date: June 1, 1991
Creator: Alexander, D. J.; Goodwin, G. M. & Bloom, E. E.
Partner: UNT Libraries Government Documents Department
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Solder fatigue reduction in point focus photovoltaic concentrator modules

Description: Solder fatigue tests have been conducted on point focus photovoltaic concentration cell assemblies to identify a baseline fatigue life and to quantify the fatigue life improvements that result using a copper-molybdenum-copper low-expansion insert between the solar cell and copper heat spreader. Solder microstructural changes and fatigue crack growth were identified using cross sections and ultrasonic scans of the fatigue solder joints. The Coffin-Manson and Total Strain fatigue models for low-c… more
Date: January 1, 1991
Creator: Hund, T. D. & Burchett, S. N.
Partner: UNT Libraries Government Documents Department
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Sodium compatibility of HT-9 and Fe-9Cr-1Mo steels

Description: Ferritic steels have been receiving significant attention for possible use as steam generator tubing, and as alternate structural materials for liquid-metal heat-transport systems in commercial fast reactors, fusion reactors, etc. The materials are chosen on the basis of their high thermal conductivity, resistance to stress-corrosion-cracking in aqueous and steam environments, favorable fabricability and fairly low cost. These steels are available in several classes based on the microstructure … more
Date: November 1, 1985
Creator: Anantatmula, R. P. & Brehm, W. F.
Partner: UNT Libraries Government Documents Department
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Microstructural and solidification cracking evaluation of electron beam welds in 304L

Description: Weld hot cracking of stainless steels is a major materials-related problem in the welding industry. This present investigation evaluates the crack susceptibility of highly-constrained EB welds made in materials whose DeLong ferrite potentials range from zero to nine FN. In addition, the effect of piece part strength level on cracking is examined. This study has revealed that these deep penetration EB welds have regions that solidify as primary austenite, even when the DeLong ferrite potential i… more
Date: January 1, 1991
Creator: Sturgill, P.L.; Campbell, R.D. & Henningsen, J.L.
Partner: UNT Libraries Government Documents Department
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Advanced Gas Cooled Nuclear Reactor Materials Evaluation and Development Program. Progress report, January 1, 1980-March 31, 1980

Description: Results are presented of work performed on the Advanced Gas-Cooled Nuclear Reactor Materials Evaluation and Development Program. The objectives of this program are to evaluate candidate alloys for Very High Temperature Reactor (VHTR) Nuclear Process Heat (NPH) and Direct Cycle Helium Turbine (DCHT) applications, in terms of the effect of simulated reactor primary coolant (helium containing small amounts of various other gases), high temperatures, and long time exposures, on the mechanical prope… more
Date: June 25, 1980
Partner: UNT Libraries Government Documents Department
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Bond-Strength Studies for 1-Mil-Diameter Gold Wires Bonded to Hybrid Microcircuit Substrates

Description: Detailed studies of the failure probability for gold wires bonded to multiplexer substrates under severe acceleration in the W79 artillery shell environments were made. The studies included: the calculated resultant pull forces exerted on the bond joints due to the W79 acceleration environments; the suitability of the loop-hook pull tests and the use of the normal Gaussian distribution theory for statistical description of bond strengths; and the probability of failure for gold wires bonded to … more
Date: December 1, 1981
Creator: Kan, Y.R. & Prantil, V.C.
Partner: UNT Libraries Government Documents Department
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Assessment of lamellar tearing

Description: Information on lamellar tearing is summarized and related to proposed ASME Code requirements. Lamellar tearing is characterized as a complex phenomenon related to poor short transverse ductility and through-thickness strain. The material, welding, and design variables that affect lamellar tearing are shown to be complex and interrelated. The commonly reported tests for assessing material susceptibility are described, with the controversy over their validity being carefully detailed. Although th… more
Date: March 1, 1978
Creator: McEnerney, J.W.
Partner: UNT Libraries Government Documents Department
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Correlation of mechanical and metallurgical parameters with the acoustic emission during tensile deformation of several metals and alloys

Description: Acoustic emission was monitored during plastic deformation under dead-weight tensile loading of polycrystalline aluminum, brass, copper, and steel. The acoustic emission data, both threshold-type and frequency-analysis type, were correlated with yield strength, stored elastic energy, strain hardening parameters, loading histories, diffusion processes, slip band motion and mosaic cell size. Major results are presented under the headings discontinuous yielding (Portevin--Le Chatelier Effect), par… more
Date: December 1, 1975
Creator: Hartman, W. F.
Partner: UNT Libraries Government Documents Department
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Tensile and fracture properties of EBR-II-irradiated V-15Cr-5Ti containing helium

Description: The alloy V-15Cr-5Ti was cyclotron-implanted with 80 appM He and subsequently irradiated in the Experimental Breeder Reactor (EBR-II) to 30 dpa. The same alloy was also irradiated in the 10, 20, and 30% cold-worked conditions. Irradiation temperatures ranged from 400 to 700/sup 0/C. No significant effects of helium on mechanical properties were found in this temperature range although the neutron irradiation shifted the temperature of transition from cleavage to ductile fracture to about 625/su… more
Date: January 1, 1986
Creator: Grossbeck, M.L. & Horak, J.A.
Partner: UNT Libraries Government Documents Department
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Scale effects in sliding friction: An experimental study

Description: Solid friction is considered by some to be a fundamental property of two contacting materials, while others consider it to be a property of the larger tribosystem in which the materials are contained. A set of sliding friction experiments were designed to investigate the hypothesis that the unlubricated sliding friction between two materials is indeed a tribosystems-related property and that the relative influence of the materials properties or those of the machine on friction varies from one s… more
Date: July 24, 1991
Creator: Blau, P.J.
Partner: UNT Libraries Government Documents Department
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Advances in materials science, Metals and Ceramics Division. Triannual progress report, February-May 1980

Description: Research is reported in the magnetic fusion energy and laser fusion energy programs, aluminium-air battery and vehicle research, geothermal research, nuclear waste management, basic energy science, and chemistry and materials science. (FS)
Date: August 1, 1980
Creator: Truhan, J.J. & Gordon, K.M. (eds.)
Partner: UNT Libraries Government Documents Department
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Fatigue Crack Initiation and Propagation in Steels Exposed to Inert and Corrosive Environments. Final Report, May 1, 1977--December 31, 1977

Description: The fatigue crack initiation life of AISI 1018 steel was investigated using compact tension specimens having sharp notch root radii. The data were analyzed using two methods for predicting initiation in strain cycling experiments. Also, another approach in which initiation is related to the stress intensity factor was developed. The next phase, that of propagation, was studied using AISI 1018 steel and a new high strength steel HY-180. The crack propagation data obtained for both steels tested … more
Date: February 1, 1978
Creator: Youseffi, K. & Finnie, I.
Partner: UNT Libraries Government Documents Department
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Experimental high temperature coefficients of compressibility and expansivity of liquid sodium and other related properties

Description: The subcooled compressibility of liquid sodium was directly measured up to 200 atm between 900 K and 1867 K, utilizing a new multi-property apparatus which was previously tested with water. The experimental data were correlated by a 6-term equation with a standard deviation of 9.2 percent. The equation can be used to estimate the subcooled compressibilities and densities of liquid sodium up to 2300 K and 500 ata. The thermal expansion of liquid sodium was also measured along the isobars 1 ata, … more
Date: January 1, 1977
Creator: Das Gupta, S.
Partner: UNT Libraries Government Documents Department
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Nonlinear, distortive phenomena in solids: Martensitic, crack, and multiscale structures

Description: This ongoing program, from the beginning of the first three year grant 1988--1991 and now in the first year of the second phase 1991--1994, has been directed at developing both an understanding of the physics underlying structural transformations in real (alloy) materials as well as new theoretical methods which adequately describe the large (nonlinear) distortions which characterize such processes. We have had a particular interest in martensitic systems, first (1988--1991) in the equilibrium … more
Date: January 1, 1992
Creator: Krumhansl, J. A. & Sethna, J. P.
Partner: UNT Libraries Government Documents Department
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