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in subjects: "Carbides"

open access

TCT hybrid preconceptual blanket design studies

The conceptual design of a tokamak fusion-fission (hybrid) reactor, which produces electric power and fissile material, has been performed in a cooperative effort between Princeton's Plasma Physics Laboratory (PPPL) and Battelle's Pacific Northwest Laboratories (PNL). PPPL, who had overall project lead responsibility, designed the fusion driver system. Its core consists of a tokamak plasma maintained in the two-component torus (TCT) mode by both D and T beams and having a single null poloidal d… more

Date: January 1, 1978

Creator: Aase, D. T.; Bampton, M. C. C.; Doherty, T. J.; Leonard, B. R.; McCann, R. A.; Newman, D. F. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Joining of ceramics for high performance energy systems. Mid-term progress report, August 1, 1979-March 31, 1980

The subject program is primarily an exploratory and demonstration study of the use of silicate glass-based adhesives for bonding silicon-base refractory ceramics (SiC, Si/sub 3/N/sub 4/). The projected application is 1250 to 2050/sup 0/F relaxing joint service in high-performance energy conversion systems. The five program tasks and their current status are as follows. Task 1 - Long-Term Joint Stability. Time-temperature-transformation studies of candidate glass adhesives, out to 2000 hours sim… more

Date: October 6, 1980

Creator: Smeltzer, C E & Metcalfe, A G

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Interaction of noble-metal fission products with pyrolytic silicon carbide

Fuel particles for the High-Temperature Gas-Cooled Reactor (HTGR) contain layers of pyrolytic carbon and silicon carbide, which act as a miniature pressure vessel and form the primary fission product barrier. Of the many fission products formed during irradiation, the noble metals are of particular interest because they interact significantly with the SiC layer and their concentrations are somewhat higher in the low-enriched uranium fuels currently under consideration. To study fission product-… more

Date: January 1, 1982

Creator: Lauf, R. J. & Braski, D. N.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Ceramic microstructures and their elucidation by imaging, diffraction and spectroscopic methods

The development and potential utilization of ceramic materials is dependent on a systematic effort involving processing, characterization and appropriate property measurements. The methods of characterization are numerous and it is important to employ the one that is appropriate to the problem both in terms of its information content and the achievable level of resolution. With the incorporation of fine probe forming capabilities in a transmission electron microscope and the development of rela… more

Date: February 1, 1992

Creator: Kirshnan, K.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Ceramic technology for Advanced Heat Engines Project

Significant accomplishments in fabricating ceramic components for advanced heat engine programs have provided evidence that the operation of ceramic parts in high-temperature engine environments is feasible. However, these programs have also demonstrated that additional research is needed in materials and processing development, design methodology, and database and life prediction before industry will have a sufficient technology base from which to produce reliable cost-effective ceramic engine… more

Date: July 1, 1991

Creator: Johnson, D. R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Fundamental spectroscopic studies of carbenes and hydrocarbon radicals

This document details activities during this reporting period topics discussed are: The first spectroscopic identification of the HCCCO and DCCCO radicals; detection of new vibrationally excited states of the carbon chain radicals CCH and CCD and the three-membered carbene ring, cyclopropenylidene; determination of an accurate structure of the cumulene carbene H{sub 2}CCC; analysis the hyperfine structure in the SiC radical; and the undertaking of a systematic search for new sulfur bearing radi… more

Date: May 1, 1992

Creator: Thaddeus, P. & Gottlieb, C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Some Scoping Experiments for a Space Reactor

Some scoping experiments were performed to evaluate fuel performance in a lithium heat pipe reactor operating at a nominal 1500K heat pipe temperature. Fuel-coolant and fuel-coolant-clad relationships showed that once a failed heat pipe occurs temperatures can rise high enough so that large concentrations of uranium can be transported by the vapor phase. Upon condensation this uranium would be capable of penetrating heat pipes adjacent to the failed pipe. The potential for propagation of failur… more

Date: July 7, 1983

Creator: Alexander, C. A. & Ogden, J. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Creep of whisker-reinforced ceramics

The results of high-temperature creep of various ceramic composites will be reviewed. In particular, creep results for Al{sub 2}O{sub 3} and Si{sub 3}N{sub 4} matrices reinforced with SiC whiskers will be emphasized. For a given temperature, stress and grain size, the creep rate of the Al{sub 2}O{sub 3} composite is usually lower than that of the ceramic matrix. In general, creep at low stresses occurs by grain boundary sliding accommodated by diffusion, whereas higher stresses lead to damage a… more

Date: January 1, 1991

Creator: Routbort, J.L; Goretta, K.C. (Argonne National Lab., IL (United States)); Dominguez-Rodriguez, A. & de Arellano-Lopez, A.R. (Seville Univ. (Spain))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Effect of irradiation-induced defects on fusion reactor ceramics

Structural, thermal, and electrical properties critical to performance of ceramics in a fusion environment can be profoundly altered by irradiation effects. Neutron damage may cause swelling, reduction of thermal conductivity, increase in dielectric loss, and either reduction or enhancement of strength depending on the crystal structure and defect content of the material. Absorption of ionizing energy inevitably leads to degradation of insulating properties, but these changes can be reduced by … more

Date: January 1, 1986

Creator: Clinard, F.W. Jr.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Fossil Energy Advanced Research and Technology Development (AR TD) Materials Program semiannual progress report for the period ending September 30, 1991

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: Report

Partner: UNT Libraries Government Documents Department

open access

Thermal strains in titanium aluminide and nickel aluminide composites

Neutron diffraction was used to measure residual thermal strains developed during postfabrication cooling in titanium aluminide and nickel aluminide intermetallic matrix composites. Silicon carbide /Ti 14Al-21Nb, tungsten and sapphire/NiAl, and sapphire and SiC-coated sapphire/NiAl{sub 25}Fe{sub 10} composites were investigated. The thermal expansion coefficient of the matrix is usually greater than that of the fibers. As such, during cooldown, compressive residual strains are generated in the … more

Date: January 1, 1992

Creator: Saigal, A. (Tufts Univ., Medford, MA (United States). Dept. of Mechanical Engineering) & Kupperman, D.S. (Argonne National Lab., IL (United States))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Corrosion of SiC and oxide-composite ceramics by a simulated steam-reformer atmosphere

To achieve higher process efficiency by using pressurized reactants and/or heat transfer fluids, the US DOE is promoting development of high-pressure heat exchanger systems under cost-sharing agreements with industrial contractors. The steam reformer would contain more than 600 tubes. Because the combination of high temperature and pressure differential of 12.7 kg/cm{sup 2} (180 psig) across the tube wall is too severe for metallic tubes, ceramic materials are being considered for reformer tube… more

Date: September 1, 1991

Creator: Federer, J.I.; Kim, H.E. & Moorhead, A.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Monitoring instrument field experiments at Oregon Institute of Technology

The field tests were conducted under reducing and oxidizing conditions. Corrosion rates with zero oxygen were about 1.1 mils per year (mpy) for both copper and steel coupons, which is quite low for carbon steel. There was a problem controlling the oxygen level in the oxygenated experiments; however, it was found that corrosion rates increased with the presence of oxygen. Corrosion rates for the steel and copper coupons were 4 and 2 mpy, respectively; copper coupled to cast iron corroded at 8 mp… more

Date: September 1, 1980

Creator: Danielson, M. J. & Smith, R. P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Mechanical properties of chemical vapor deposited coatings for fusion reactor application

Chemical vapor deposited coatings of TiB/sub 2/, TiC and boron on graphite substrates are being developed for application as limiter materials in magnetic confinement fusion reactors. In this application severe thermal shock conditions exist and to do effective thermo-mechanical modelling of the material response it is necessary to acquire elastic moduli, fracture strength and strain to fracture data for the coatings. Four point flexure tests have been conducted from room temperature to 2000/su… more

Date: January 1, 1980

Creator: Mullendore, A. W.; Whitley, J. B.; Pierson, H. O. & Mattox, D. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Superconductivity in solid solutions of transition metal carbides. [NbC-TaC]

No Description Available.

Date: June 10, 1964

Creator: Wells, M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Sb interactions with TaC precipitates and Cu in ion-implanted. cap alpha. -Fe

The interactions of Sb with the other species implanted into Fe to form Fe-Ta-C-Sb and Fe-Cu-Sb alloys have been examined with transmission electron microscopy and Rutherford backscattering following annealing at 873/sup 0/K. Trapping of Sb at TaC precipitates is observed in the former alloy just as was previously observed in Fe-Ti-C-Sb. In Fe-Cu-Sb, Sb interactions are governed by the atomic ratio of Sb to Cu. For ratios between 0.2 to 0.4, the compound ..beta..-Cu/sub 3/Sb was observed to for… more

Date: January 1, 1980

Creator: Follstaedt, D. M. & Myers, S. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Dispersion aspects of silicon carbide gelcasting

The principal objective of this research was to increase the solid loading of silicon carbide (SiC) powder, in an appropriate liquid medium, to a level that is useful for gelcasting technology. A number of factors that determine the maximum concentration of silicon carbide that can be incorporated into a pourable ceramic suspension have been identified. The pH of the system is the most critical processing parameter. Its proper adjustment (pH 11 to 13) allows SiC concentrations exceeding 50%, ba… more

Date: September 1, 1991

Creator: Bleier, A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Advanced Fuel Systems Program. ERDA-RRD briefing, October 14, 1976

No Description Available.

Date: January 1, 1976

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Performance potential of (Th,U) carbide and (Th,U) nitride fuel in 1200 MWe LMFBR's

An evaluation of the performance potential of thorium-uranium carbide and nitride fuel in 1200 MW(e) homogeneous and heterogeneous LMFBR's has been completed. Comparisons were done with 9.40 mm outer diameter, 0.38 mm cladding fuel pins at a selected peak (3 sigma) linear power of 98.4 kW/m for all cores. Breeding ratios for the homogeneous (Th,U)C and (Th,U)N cores are 1.12 and 1.16, respectively. In the heterogeneous cores the breeding ratios are 0.08 to 0.09 greater. A comparative breeding r… more

Date: April 1, 1978

Creator: Caspersson, S. A. & Kulwich, M. R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Interim design report: fuel particle crushing. [Double-roll crusher]

The double-roll fuel particle crusher was developed to fracture the silicon carbide coatings of Fort St. Vrain (FSV) fertile and fissile and large high-temperature gas-cooled reactor (LHTGR) fissile fuel particles. The report details the design task for the fuel particle crusher, including historical test information on double-roll crushers for carbide-coated fuels and the design approach selected for the cold pilot plant crusher, and shows how the design addresses the equipment goals and opera… more

Date: November 1, 1977

Creator: Baer, J. W.; Strand, J. B.; Cook, E. J. & Miller, C. M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Tests of a Higgins contactor for the engineering-scale resin loading of uranium

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: Report

Partner: UNT Libraries Government Documents Department

open access

Fuel systems for compact fast space reactors

About 200 refractory metal clad ceramic fuel pins have been irradiated in thermal reactors under the 1200 K to 1550 K cladding temperature conditions of primary relevance to space reactors. This paper reviews performance with respect to fissile atom density, operating temperatures, fuel swelling, fission gas release, fuel-cladding compatibility, and consequences of failure. It was concluded that UO/sub 2/ and UN fuels show approximately equal performance potential and that UC fuel has lesser po… more

Date: December 1, 1983

Creator: Cox, C.M.; Dutt, D.S. & Karnesky, R.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Mine roof drill bits that save money

Sandia National Laboratories, Albuquerque, NM, has developed advanced technology roof bolt drill bits which have demonstrated longer life, higher penetration rates at lower thrust and torque, and lower specific energy than conventional roof bolt drill bits. This is achieved through use of advanced technology cutting materials and novel bit body designs. These bits have received extensive laboratory and mine testing. Their performance has been evaluated and estimates of their value in reducing c… more

Date: April 1, 1982

Creator: Ford, L.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Compact nuclear power systems based on particle bed reactors

Compact, low cost nuclear power systems with an extremely low radioactive inventory are described. These systems use the Particle Bed Reactor (PBR), in which HTGR particle fuel is contained in packed beds that are changed daily. The small diameter particle fuel (500 ..mu..m) is directly cooled utilizing the large heat transfer area available (7.8 m/sup 2//liter), thus allowing high bed power densities (MW/liter).

Date: January 1, 1986

Creator: Horn, F. L.; Powell, J. R.; Steinberg, M. & Takahashi, H.

Item Type: Article

Partner: UNT Libraries Government Documents Department