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Crack growth and CREEP-fatigue interaction behavior of 2 1/4 Cr--1 Mo steel

Description: Cyclic strain-controlled fatigue tests and cyclic tension-tension crack growth tests employing precracked specimens are being conducted at RT to 593$sup 0$C in various environments including air, steam, vacuum, and impure He. Fatigue and creep-fatigue data at 482 and 538$sup 0$C, effects of temperature, waveform, and hold time or strain rate of fatigue life; comparisons with linear damage rule; subcritical crack growth tests; effects of variation of min to max load ratio; and effects of environment (air, steam, He) on crack growth are given. 15 figures. (DLC)
Date: January 1, 1975
Creator: Brinkman, C.R.
Partner: UNT Libraries Government Documents Department

Creep-fatigue effects in structural materials used in advanced nuclear power generating systems

Description: Various aspects of time-dependent fatigue behavior of a number of structural alloys in use or planned for use in advanced nuclear power generating systems are reviewed. Materials included are types 304 and 316 stainless steel, Fe-2 1/4 Cr-1 Mo steel, and alloy 800H. Examples of environmental effects, including both chemical and physical interaction, are presented for a number of environments. The environments discussed are high-purity liquid sodium, high vacuum, air, impure helium, and irradiation damage, including internal helium bubble generation.
Date: January 1, 1980
Creator: Brinkman, C.R.
Partner: UNT Libraries Government Documents Department

Overview of U. S. efforts directed towards development of mechanical properties data in support of FBR development

Description: The object of U.S. Breeder Reactor Program associated with primary and secondary circuit structural materials is to develop a design data base and associated design technology on commercially available material as well as new alloys. The commercially available materials include ASIA 316 and 304. Chromium--molybdenum steels and alloy 800H. (FS)
Date: January 1, 1978
Creator: Brinkman, C.R.
Partner: UNT Libraries Government Documents Department

Progress in understanding the mechanical behavior of pressure-vessel materials at elevated temperatures

Description: Progress during the 1970's on the production of high-temperature mechanical properties data for pressure vessel materials was reviewed. The direction of the research was toward satisfying new data requirements to implement advances in high-temperature inelastic design methods. To meet these needs, servo-controlled testing machines and high-resolution extensometry were developed to gain more information on the essential behavioral features of high-temperature alloys. The similarities and differences in the mechanical response of various pressure vessel materials were identified. High-temperature pressure vessel materials that have received the most attention included Type 304 stainless steel, Type 316 stainless steel, 2 1/4 Cr-1 Mo steel, alloy 800H, and Hastelloy X.
Date: January 1, 1981
Creator: Swindeman, R.W. & Brinkman, C.R.
Partner: UNT Libraries Government Documents Department

Twin boundary cavitation in aged type 304 stainless steel

Description: A transition from grain to twin boundary cavitation was observed in aged- and-creep-tested type 304 stainless steel. Evidence of twin boundary cavitation has also been observed for unaged material under certain test conditions. This same behavior was also found in aged type 316 stainless steel. Several possible reasons have been suggested for the absence of frequently observed grain boundary cavitation. (auth)
Date: October 1, 1975
Creator: Sikka, V.K.; Swindeman, R.W. & Brinkman, C.R.
Partner: UNT Libraries Government Documents Department

Overview of the U. S. programs on properties of primary circuit materials

Description: The objective of U.S. Breeder Reactor Programs associated with primary circuit structural materials is to develop the design data base and associated design technology on existing commercially available materials as well as new alloys. This will permit economic operation of components at acceptable levels of plant availability and at up to 40-year lifetimes for inaccessible components. Long-term component reliability, elevated-temperature service within the creep range, and resistance to sodium attack and irradiation damage, along with design in compliance with ASME Codes and RDT Specifications, have required that the U.S. programs be directed toward contributing knowledge in a number of areas. These areas, relating to material deformation, failure modes, compatibility, fabrication, long-term behavior, irradiation damage, and availability will be discussed. The U.S. Structural Material Programs concerned with primary-circuit components will be reviewed, and their current and future contributions to knowledge of these areas will be explained.
Date: January 1, 1977
Creator: Brinkman, C.R.; Sikka, V.K. & Booker, M.K.
Partner: UNT Libraries Government Documents Department

Elevated-Temperature Mechanical Properties of an Advanced Type 316 Stainless Steel

Description: Type 316FR stainless steel is a candidate material for the Japanese Demonstration Fast Breeder Reactor Plant to be built in Japan early in the next century. Like type 316L(N), it is a low-carbon grade of stainless steel with a more closely specified nitrogen content and chemistry optimized to enhance elevated-temperature performance. Early in 1994, under sponsorship of The Japan Atomic Power Company, work was initiated at Oak Ridge National Laboratory (ORNL) aimed at obtaining an elevated-temperature mechanical-properties database on a single heat of this material. The product form was 50-mm plate manufactured by the Nippon Steel Corporation. Data include results from long-term creep-rupture tests conducted at temperatures of 500 to 600 C with test times up to nearly 40,000 h, continuous-cycle strain-controlled fatigue test results over the same temperature range, limited creep-fatigue data at 550 and 600 C, and tensile test properties from room temperature to 650 C. The ORNL data were compared with data obtained from several different heats and product forms of this material obtained at Japanese laboratories. The data were also compared with results from predictive equations developed for this material and with data available for type 316 and type 316L(N) stainless steel.
Date: August 1, 1999
Creator: Brinkman, C.R.
Partner: UNT Libraries Government Documents Department

Development of Aluminum Bridge Deck System with Reynolds Metals Company

Description: Currently, there are many structurally-deficient and obsolete bridges in the US highway system. The expected cost for repair and replacement is enormous; therefore, more cost-effective materials and construction methodology must be sought. Reynolds Metals Company formed a vertical consortium to develop and market a cost-effective, innovative, lightweight, corrosion resistant aluminum bridge deck system based on hollow aluminum shapes that could be welded together in the shop to form deck panels. Panels would be shipped to the construction sites for final assembly, which uses connections along longitudinal edges. These deck panels would replace conventional steel or concrete panels. An epoxy-gravel wearing surface would be applied to the top side of the deck to provide a durable, skid-resistant surface. However, before this deck system could be widely utilized, the overall structural integrity had to be fully demonstrated. Reynolds Metals Company and Oak Ridge National Laboratory (ORN L) entered in a Cooperative Research and Development Agreement (CRADA) to conduct a number of fundamental investigations into potentially critical technical areas over approximately a four-year period.
Date: April 1, 1999
Creator: Brinkman, C. R. & Hayden, W. H.
Partner: UNT Libraries Government Documents Department

Estimates of time-dependence fatigue behavior of type 316 stainless steel subject to irradiation damage in fast breeder and fusion power reactor systems. [Fluence 1--2. 63 x 10/sup 26/ n/m/sup 2/ (E > 0. 1 MeV/ at 593/sup 0/C]

Description: Cyclic lives obtained from strain controlled fatigue tests at 593/sup 0/C from specimens irradiated to a fluence of 1 to 2.63 x 10/sup 26/ n/m/sup 2/ (E greater than 0.1 MeV) were compared to predictions based on the method of strainrange partitioning. When appropriate tensile and creep-rupture ductilities were employed reasonably good estimates of the influence of hold periods and irradiation damage on the fully reversed fatigue life of type 316 stainless steel could be made. Ductility values for 20 percent cold-worked type 316 stainless steel specimens irradiated in a mixed spectrum fission reactor were used to estimate fusion reactor first wall lifetime. The ductility values were from irradiations that simulate the environment of the first wall of a fusion reactor. Neutron wall loadings ranging from 2 to 5 MW/m/sup 2/ were used. Results, although conjectural because of the many assumptions, tended to show that 20 percent cold-worked type 316 stainless steel could be used as a first wall material meeting a 7.5 to 8.5 MW-year/m/sup 2/ lifetime goal provided the neutron wall loading does not exceed more than about 2 MW/m/sup 2/. Results were obtained for an air environment, and it is expected that the actual vacuum environment will extend lifetime beyond 10 MW-year/m/sup 2/.
Date: July 10, 1978
Creator: Brinkman, C.R.; Liu, K.C. & Grossbeck, M.L.
Partner: UNT Libraries Government Documents Department

High-temperature low-cycle fatigue and tensile properties of Hastelloy X and alloy 617 in air and HTGR-helium

Description: Results of strain controlled fatigue and tensile tests are presented for two nickel base solution hardened alloys which are reference structural alloys for use in several high temperature gas cooled reactor concepts. These alloys, Hastelloy X Inconel 617, were tested at temperatures ranging from room temperature to 871/sup 0/C in air and impure helium. Materials were tested in the solution annealed as well as in the pre-aged condition where aging consisted of isothermal exposure at one of several temperatures for periods of up to 20,000 h. Comparisons are also given between the strain controlled fatigue lives of these alloys and several other commonly used alloys all tested at 538/sup 0/C.
Date: January 1, 1981
Creator: Strizak, J.P.; Brinkman, C.R. & Rittenhouse, P.L.
Partner: UNT Libraries Government Documents Department

Tensile creep behavior and cyclic fatigue/creep interaction of hot- isostatically pressed Si sub 3 N sub 4

Description: Tensile creep data are reported for a high-performance grade of hot isostatically pressed Si{sub 3}N{sub 4} that is currently being investigated as a candidate material for advanced heat engine applications. Specimens were tested in pure uniaxial tension at temperatures ranging from 1200 to 1370{degree}C. Creep strain was measured with an optical strain extensometer until creep rupture occurred, in some cases for periods in excess of 2000 h. To study the effects of various preloading material histories on creep behavior, specimens were prepared and tested in several conditions, i.e., unannealed, annealed, or precycled. Test results show that either treatment by thermal annealing or by precycling at 1370{degree}C can dramatically modify the initial transient creep behavior and enhance the resistance to creep deformation and hence the creep-rupture lifetime. However, the influence of the preloading histories on creep rate was diminished by high temperature exposure after about 500 h of testing. The rupture lifetime of the precycled specimen at 1370{degree}C was significantly higher than those of the unannealed and annealed specimens. In contrast, no significant extension of the creep-rupture lifetime was observed for a precycled specimen tested at 1300{degree}C. Steady-state creep was absent in some cases under certain conditions of temperature, stress, and heat treatment. Little or no tertiary creep was usually detected before specimen fracture occurred. The steady-state creep rate of this material was found to be a function of applied stress, temperature, and possibly the level of crystallinity in the intergranular phase. 9 refs., 15 figs.
Date: January 1, 1991
Creator: Liu, K.C.; Pih, H.; Stevens, C.O. & Brinkman, C.R.
Partner: UNT Libraries Government Documents Department

Tensile and cyclic fatigue behavior of SiC whisker-reinforced Al{sub 2}O{sub 3} at room and elevated temperatures

Description: Uniaxial tensile and cyclic fatigue data are reported for a commercial grade of silicon carbide whisker-reinforced alumina matrix composite (SiC{sub w}/Al{sub 2}O{sub 3}) tested at room and elevated temperatures. The data show that addition of short SiC{sub w} (30 vol%) in Al{sub 2}O{sub 3} can significantly increase room temperature tensile strength and resistance to cyclic fatigue of monolithic Al{sub 2}O{sub 3} by {approximately} 40% and {approximately} 100%, respectively, bringing the high-cycle fatigue strength (> 10{sup 5} cycle range) to {approximately} 95% of its tensile strength. These dramatic improvements in tensile and fatigue behavior were attributed to the presence of SiC{sub w} which effectively inhibited cyclic fatigue crack growth. The composite further exhibited excellent retention of tensile and cyclic fatigue strengths at elevated temperatures as high as 1,000 C for practical engineering applications.
Date: June 1, 1996
Creator: Liu, K.C.; Stevens, C.O. & Brinkman, C.R.
Partner: UNT Libraries Government Documents Department

Creep and creep-rupture behavior of a continuous strand, swirl mat reinforced polymer composite in automotive environments

Description: Creep and creep-rupture behavior of an isocyanurate based polyurethane matrix with a continuous strand, swirl mat E-glass reinforcement was investigated for automotive applications. The material under stress was exposed to various automobile service environments. Results show that environment has substantial effects on its creep and creep-rupture properties. Proposed design guide lines and stress reduction factors were developed for various automotive environments. These composites are considered candidate structural materials for light weight and fuel efficient automobiles of the future.
Date: December 31, 1998
Creator: Ren, W. & Brinkman, C.R.
Partner: UNT Libraries Government Documents Department

Development of ASTM standards in support of advanced ceramics -- continuing efforts

Description: An update is presented of the activities of the American Society for Testing and Materials (ASTM) Committee C-28 on Advanced Ceramics. Since its inception in 1986, this committee, which has five standard producing subcommittees, has written and published over 32 consensus standards. These standards are concerned with mechanical testing of monolithic and composite ceramics, nondestructive examination, statistical analysis and design, powder characterization, quantitative microscopy, fractography, and terminology. These standards ensure optimum material behavior with physical and mechanical property reproducibility, component reliability, and well-defined methods of data treatment and material analysis for both monolithic and composite materials. Committee C-28 continues to sponsor technical symposia and to cooperate in the development of international standards. An update of recent and current activities as well as possible new areas of standardization work will be presented.
Date: February 1, 1998
Creator: Brinkman, C.R.
Partner: UNT Libraries Government Documents Department

A technique to achieve uniform stress distribution in compressive creep testing of advanced ceramics at high temperatures

Description: A technique to achieve stable and uniform uniaxial compression is offered for creep testing of advanced ceramic materials at elevated temperatures, using an innovative self-aligning load-train assembly. Excellent load-train alignment is attributed to the inherent ability of a unique hydraulic universal coupler to maintain self-aligning. Details of key elements, design concept, and pricniples of operation of the self-aligning coupler are described. A method of alignment verification using a strain-gaged specimen is then discussed. Results of verification tests indicate that bending below 1.5% is routinely achievable usin the load-train system. A successful compression creep test is demonstrated using a dumbbell-shpaed Si nitride specimen tested at 1300 C for over 4000 h.
Date: May 1, 1996
Creator: Liu, K.C.; Stevens, C.O.; Brinkman, C.R. & Holshauser, N.E.
Partner: UNT Libraries Government Documents Department

Overview of ASTM standard activities in support of advanced structural ceramics development

Description: An overview is presented of the activities of ASTM Committee C-28 on Advanced Ceramics. This activity originated in 1986 when it became apparent that advanced ceramics were being considered for extensive use in applications such as advanced heat engines, heat exchangers, combustors, etc. in aerospace and energy conservation activities. These applications require optimum material behavior with physical and mechanical property reproducibility, component reliability, and well defined methods of data treatment and material analysis for both monolithic and composite ceramic materials. As new materials are introduced into the market place, these issues are best dealt with via standard methods. Therefore, a progress report is given describing activities of the five standard writing subcommittees who support the ASTM Committee C-28 effort. Accomplishments to date are given, as well as likely future activities, including a brief summary of joint cooperative efforts with international standard formulating organizations.
Date: July 1, 1995
Creator: Brinkman, C.R.; Quinn, G.D. & McClung, R.W.
Partner: UNT Libraries Government Documents Department

Fatigue crack propagation in 2 1/4 Cr-1 Mo steel

Description: The fatigue crack propagation of 2 1/4 Cr-1 Mo steel was examined in air over a wide range of experimental conditions. The fatigue crack growth rate was found to: generally increase monotonically with increasing temperature from 172/sup 0/ to 866/sup 0/K, except in the range where dynamic strain aging occurs, near 644/sup 0/K; increase with decreasing frequency at room temperatures above 783/sup 0/K - this frequency dependence was not observed below 783/sup 0/K; and increase with increases in mean stress. The results were evaluated, and a simple empirical model was developed to yield estimates of average and upper limit crack growth rates as a function of temperature, frequency, and effective stress intensity. However, the model is not applicable in the low region where threshold effects become important since insufficient data were available in that range.
Date: January 1, 1979
Creator: Corwin, W.R.; Booker, M.K.; Booker, B.L.P. & Brinkman, C.R.
Partner: UNT Libraries Government Documents Department

Low heat rejection diesel ceramic coupon tests

Description: Results are reported from studies in which several monolithic ceramic materials in the form of modulus-of-rupture bars were exposed for 100 h to the combustion conditions found in either a small single- or two-cylinder diesel engine. Fuels included a standard Phillips D-2 diesel or synthetic mixture of the Phillips D-2 and an aromatic blend. The ceramics included two commercial grades of partially stabilized zirconia (PSZ-TS and PSZ-MS), silicon nitride (GTE WESGO SNW-1000 and Norton NT-154), and (Hexoloy SA) silicon carbide. Significant reductions in postexposure four-point bend fracture strength occurred in the PSZ-TS material irrespective of whether it was exposed in the single- or two-cylinder engine. Only a small decrease in fracture strength occurred in the PSZ-MS material, and essentially no decrease in fracture strength occurred in the silicon nitride (GTE WESGO SNW-1000) when tested at room temperature. The Norton NT-154 silicon nitride was tested at both room temperature and at 700{degree}C over several strain rates ranging from 1 {times} 10{sup {minus}4} to 1 {times} 10{sup {minus}7}s{sup {minus}1}. Room temperature tests indicated that the engine exposed bars actually showed a slight increase in average strength, 830 MPa, versus 771 MPa for the unexposed material. Elevated temperature strength comparisons showed no reduction in strength due to previous engine exposure. Hexoloy SA silicon carbide showed no reduction in fracture strength when tested at 700{degree}C. 4 refs., 12 figs., 1 tab.
Date: January 1, 1991
Creator: Brinkman, C.R.; Liu, K.C.; Graves, R.L. & West, B.H.
Partner: UNT Libraries Government Documents Department

Creep and creep-rupture behavior of Alloy 718

Description: Data obtained from creep and creep-rupture tests conducted on 18 heats of Alloy 718 were used to formulate models for predicting high temperature time dependent behavior of this alloy. Creep tests were conducted on specimens taken from a number of commercial product forms including plate, bar, and forgoing material that had been procured and heat treated in accordance with ASTM specifications B-670 or B-637. Data were obtained over the temperature range of 427 to 760{degree}C ad at test times to about 87,000 h. Comparisons are given between experimental data and the analytical models. The analytical models for creep-rupture included one based on lot-centering regression analysis and two based on the Minimum Commitment Method. A master'' curve approach was used to develop and equation for estimating creep deformation up to the onset of tertiary creep. 11 refs., 13 figs.
Date: January 1, 1991
Creator: Brinkman, C.R.; Booker, M.K. & Ding, J.L.
Partner: UNT Libraries Government Documents Department