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Evaluation of tubular ceramic heat exchanger materials in acidic coal ash from coal-oil-mixture combustion. [Sialon; alumina; CVD, sintered, and siliconized SiC]

Description: Tubes of five ceramic materials were exposed to the hot combustion gases from a coal-oil-mixture (COM) fuel in the Ceramic Recuperator Analysis Facility (CRAF) at about 1200/sup 0/C for about 500 h. Siliconized SiC, sintered ..cap alpha..-SiC, and chemically vapor deposited (CVD) SiC survived the long-term exposure with no major visible degradation. The alumina and sialon tubes were cracked extensively. Acidic coal slag deposited extensively on the upstream surface of all tubes. During cooldown… more
Date: December 1, 1981
Creator: Ferber, M. K. & Tennery, V. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High-temperature corrosion of Nicalon reg sign /SiC composites

Description: The elevated-temperature stability of Nicalon{reg sign} (Nippon Carbon Company, Tokyo, Japan)/SiC composites with a graphitic carbon interface layer in oxidizing and simulated fossil fuel environments was investigated. Composite specimens with and without an external SiC surface coating were oxidizing in air and exposed to a variety of combustion environments at a temperature of 1273 K. A burner rig furnace was constructed for simulating corrosive fossil fuel environments containing water vapor… more
Date: August 1, 1991
Creator: Lowden, R. A. & James, R. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fossil Energy Advanced Research and Technology Development (AR TD) Materials Program semiannual progress report for the period ending September 30, 1991

Description: The objective of the Fossil Energy Advanced Research and Technology Development Materials Program is to conduct research and development on materials for fossil energy applications with a focus on the longer-term and generic needs of the various fossil fuel technologies. The Program includes research aimed toward a better understanding of materials behavior in fossil energy environments and the development of new materials capable of substantial enhancement of plant operations and reliability. … more
Date: April 1, 1992
Creator: Judkins, R.R. & Cole, N.C. (comps.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Downhole steam generation: material studies

Description: One enhanced oil recovery technique for extracting heavy crude from deep reservoirs by steam at the bottom of an injection well. Development of a downhole steam generator that will produce steam and inject it into formations at depths greater than 2500 feet is one objective of a Department of Energy/Sandia National Laboratories development effort - Project DEEP STEAM. Extensive material studies have been performed in support of Project DEEP STEAM; current efforts are devoted primarily to the se… more
Date: January 1, 1982
Creator: Beauchamp, E.K.; Weirick, L.J. & Muir, J.F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Formation and modification of surface alloys by excimer laser melting and resolidification

Description: The use of pulsed lasers operating in the ultra-violet for the formation and modification of metal alloys opens a range of processing techniques which offer the precision of ion beam techniques but at much higher processing rates. In addition, excimer laser surface processing offers the possibility of new surface modification technologies. Most metals have low reflectivities in the uv, so laser light is coupled strongly to the surface. The short pulse length of these lasers, along with a shallo… more
Date: January 1, 1989
Creator: Jervis, T.R.; Nastasi, M. & Hirvonen, J.P. (Los Alamos National Lab., NM (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fundamental alloy design of oxide ceramics and their composites

Description: The main research was on microstructural development of oxide ceramics. Projects were completed and the publications given. Abstracts are given on: Reactive CeO[sub 2]powders by homogeneous precipitation, SiC whisker-reinforced lithium aluminosilicate composite, solute drag on grain boundary in ionic solids (space charge effect), in-situ alumina/aluminate platelet composites, exaggerated texture and grain growth of superplastic silicon nitride (SiAlON), hot extrusion of ceramics, control of gra… more
Date: January 1, 1992
Creator: Chen, I.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Evaluation of Advanced Materials: Final Report

Description: Cemented tungsten carbides with a binder level in the range of 5 to 6 percent exhibited the best resistance to erosion for this class of materials. Other practical cermet meterials were diamond - Si/SiC, Al/sub 2/O/sub 3/-B/sub 4/C-Cr, and B/sub 4/C-Co. SiAlON exhibited erosion resistance equivalent to the best WC-cermet. The only coating system to show promise of improved erosion resistance was CVD TiB/sub 2/ on cemented TiB/sub 2/-Ni. Cracking and/or spalling of a TiC coating and a proprietar… more
Date: November 18, 1982
Creator: Wright, I. G.; Clauer, A. H.; Shetty, D. K.; Tucker, T. R. & Stropki, J. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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DOE advanced thermionic technology program, progress report No. 46, January, February, March 1981

Description: The primary long-term goal is to improve thermionic performance to the level that thermionic topping of fossil-fuel power plants becomes technically possible and economically attractive. An intermediate goal is to operate a thermionic module in a powerplant during the mid-1980's. A short-term goal is to demonstrate reliable thermionic operation in a combustion environment. Progress made during the three-month period from January through March 1981 is reported. During this period, significant ac… more
Date: January 1, 1981
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High temperature filter materials

Description: Objectives of this program are to identify the potential long-term thermal/chemical effects that advanced coal-based power generating system environments have on the stability of porous ceramic filter materials, as well as to assess the influence of these effects on filter operating performance and life. We have principally focused our efforts on developing an understanding of the stability of the alumina/mullite filter material at high temperature (i.e., 870, 980, and 1100[degrees]C) under oxi… more
Date: January 1, 1992
Creator: Alvin, M. A.; Lippert, T. E.; Bachovchin, D. M. & Tressler, R. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development of processes and equipment for the refabrication of HTGR fuels

Description: Refabrication is in the step in the HTGR thorium fuel cycle that begins with a nitrate solution containing /sup 238/U and culminates in the assembly of this material into fuel elements for use in an HTGR. Refabrication of HTGR fuel is essentially a manufacturing operation and consists of preparation of fuel kernels, application of multiple layers of pyrolytic carbon and SiC, preparation of fuel rods, and assembly of fuel rods in fuel elements. All the equipment for refabrication of /sup 238/U-c… more
Date: June 1, 1976
Creator: Sease, J. D. & Lotts, A. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tests of a Higgins contactor for the engineering-scale resin loading of uranium

Description: The loading of uranium on weak-acid ion exchange resin is a basic step in the production of fuel particles for high-temperature gas-cooled reactors (HTGRs). In the work reported here, an engineering-scale continuous resin loader (2-in.-ID Higgins contactor) was tested with existing engineering-scale process equipment. The Higgins contactor was first successfully used to convert Na/sup +/-form resin to the H/sup +/-form; then it was evaluated as a uranium loader. Results show that the 2-in.-ID H… more
Date: January 1, 1978
Creator: Spence, R. D. & Haas, P. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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(Tribology conferences and forums)

Description: The principal meeting attended during this trip was the Japan International Tribology Conference Nagoya 1990. The conference encompassed a wide range of topics, including the tribology of ceramics, the tribology in high-performance automobiles, and many aspects of lubrication technology. Associated forums were also held on the tribology of advanced ceramics, on solid lubrication, and on automotive lubricants. Presentations made during the latter forum discussed anticipated trends in engine deve… more
Date: November 30, 1990
Creator: Yust, C.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High Temperature Alkali Corrosion of Ceramics in Coal Gas

Description: High temperature alkali corrosion has been known to cause premature failure of ceramic components used in advanced high temperature coal combustion systems such as coal gasification and clean-up, coal fired gas turbines, and high efficiency heat engines. The objective of this research is to systematically evaluate the alkali corrosion resistance of the most commonly used structural ceramics including silicon carbide, silicon nitride, cordierite, mullite, alumina, aluminum titanate, zirconia, an… more
Date: May 27, 1992
Creator: Pickrell, G. R.; Sun, T. & Brown, J. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A summary of high-temperature electronics research and development

Description: Current and future needs in automative, aircraft, space, military, and well logging industries require operation of electronics at higher temperatures than today's accepted limit of 395 K. Without the availability of high-temperature electronics, many systems must operate under derated conditions or must accept severe mass penalties required by coolant systems to maintain electronic temperatures below critical levels. This paper presents ongoing research and development in the electronics commu… more
Date: October 18, 1991
Creator: Thome, F. V. & King, D. B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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DOE/JPL advanced thermionic technology program. Progress report No. 43

Description: Progress made during the three-month period from April through June 1980 is described, significant accomplishments include: 1) demonstration of over 3000 hours of stable operation (Converter No. 228: CVD Silicon Carbide No. 2) in a combustion atmosphere at a hot shell temperature of around 1650 K with a barrier index of 2.1 eV; 2) TRW analysis of the hot shell-emitter temperature of Converter No. 218 (5120 hours of flame-heated operation at emitter temperature at, or above, 1600 K) showed no li… more
Date: January 1, 1980
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Excimer laser surface modification: Process and properties

Description: Surface modification can improve materials for structural, tribological, and corrosion applications. Excimer laser light has been shown to provide a rapid means of modifying surfaces through heat treating, surface zone refining, and mixing. Laser pulses at modest power levels can easily melt the surfaces of many materials. Mixing within the molten layer or with the gas ambient may occur, if thermodynamically allowed, followed by rapid solidification. The high temperatures allow the system to ov… more
Date: January 1, 1992
Creator: Jervis, T. R.; Nastasi, M. (Los Alamos National Lab., NM (United States)) & Hirvonen, J. P. (Technical Research Institute, Espoo (Finland). Metallurgy Lab.)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Assessment of materials for use in a solar ceramic receiver for chemical process heat

Description: Candidate ceramic matrials were evaluated on the basis of two potential temperature operating regimes: 600 to 1300/sup 0/C (1100 to 2400/sup 0/F) and 1300 to 2200/sup 0/C (2400 to 4000/sup 0/F). Discussion of properties important to the proposed application includes thermal shock resistance, tensile strength, creep resistance, oxidation resistance, vaporization rate, chemical inertness to process reactants and products, cost, and fabricability. Many ceramic materials were considered for the 600… more
Date: February 1, 1979
Creator: Tennery, V. J. & Weber, G. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Ceramics for applications in fusion systems

Description: Six critical applications for ceramics in fusion systems are reviewed, and structural and electrical problem areas discussed. Fusion neutron radiation effects in ceramics are considered in relation to fission neutron studies. A number of candidate materials are proposed for further evaluation.
Date: January 1, 1979
Creator: Clinard, F.W. Jr.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High-temperature gas-cooled reactor technology development program. Annual progress report for period ending December 31, 1982

Description: During 1982 the High-Temperature Gas-Cooled Reactor (HTGR) Technology Program at Oak Ridge National Laboratory (ORNL) continued to develop experimental data required for the design and licensing of cogeneration HTGRs. The program involves fuels and materials development (including metals, graphite, ceramic, and concrete materials), HTGR chemistry studies, structural component development and testing, reactor physics and shielding studies, performance testing of the reactor core support structur… more
Date: June 1, 1983
Creator: Kasten, P. R.; Rittenhouse, P. L.; Bartine, D. E. & Sanders, J. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Advanced Researech and Technology Development fossil energy materials program: Semiannual progress report for the period ending September 30, 1988

Description: The objective of the ARandTD Fossil Energy Materials Program is to conduct research and development on materials for fossil energy applications with a focus on the longer-term and generic needs of the various fossil fuel technologies. The program includes research aimed toward a better understanding of materials behavior in fossil energy environments and the development of new materials capable of substantial enhancement of plant operations and reliability. The ORNL Fossil Energy Materials Prog… more
Date: January 1, 1989
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Radiation-disorder and Aperiodicity in Irradiated Ceramics

Description: This final technical report documents the accomplishments of the program of research entitled Radiation Disorder and Aperiodicity in Irradiated Ceramics'' for the period June 22, 1989--June 21, 1992. This research forms the latest part on an on-going program, begun at MIT in 1983 under DOE support, which has had as its objectives investigation of the responses in radiation environments of ceramics heavily-irradiated with electrons, neutrons and ions, with potential applications to fusion energy… more
Date: January 1, 1992
Creator: Hobbs, L.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Materials technology for coal-conversion processes. Eleventh quarterly report, April--June 1977

Description: Silicon-carbide refractories with various bond systems exposed to molten slag at 1500/sup 0/C for 500 h in Run 4 showed virtually no attack. The resistance of the silicon carbide to slag attack is attributed to large thermal fluxes induced by water-cooled chills applied to the cold faces. Magnesia-chromia refractories exposed to molten slag at 1500/sup 0/C for 500 h in Run 5 were somewhat less resistant to slag attack than the silicon-carbide refractories. In-situ erosive-wear measurements on t… more
Date: January 1, 1977
Creator: Ellingson, W A
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fossil Energy Materials Program conference proceedings

Description: The US Department of Energy Office of Fossil Energy has recognized the need for materials research and development to assure the adequacy of materials of construction for advanced fossil energy systems. The principal responsibility for identifying needed materials research and for establishing a program to address these needs resides within the Office of Technical Coordination. That office has established the Advanced Research and Technology Development (AR and TD) Fossil Energy Materials Progr… more
Date: August 1, 1987
Creator: Judkins, R.R. (comp.)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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