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[News Script: Apartment Fire]

Description: Script from the WBAP-TV station in Fort Worth, Texas, covering a news story about a fire in a Dallas apartment building.
Date: October 15, 1957
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Item Type: Refine your search to only Script
Partner: UNT Libraries Special Collections
captions transcript

[News Clip: Hammons]

Description: Video footage from the WBAP-TV station in Fort Worth, Texas to accompany a news story about a Fort Worth man being credited with stabbing a woman while having no memory of the incident.
Date: December 22, 1957
Duration: 49 seconds
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Item Type: Refine your search to only Video
Partner: UNT Libraries Special Collections
open access

Strengthening and Toughening of Brittle Materials. Progress Report, January 31, 1973--January 31, 1974

Description: Studies were conducted on spherical particle and fibrous composites. The six reprints deal with: three-dimensional finiteelement analysis, effects of interface on mechanical properties of low aspect ratio fiber composites, reinforcement of epoxy resins with potassium titanate whiskers, mechanical properties of glass bead-filled epoxy composites, and interfacial layer effects on properties of composites. (DLC)
Date: January 1, 1974
Creator: Broutman, Lawrence J. & Mallick, P K
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Recovery of crystallinity in ground calcite

Description: Recovery processes by thermal treatment and recrystallization are examined in a calcite specimen severely disordered by ball milling. As the annealing temperature is increased, restructuring in the bulk lags behind the recovery of crystalline perfection in the surface regions. Surface reordering is significant at temperatures as low as 150 to 175/sup 0/C and is rapidly completed at 400/sup 0/C. Annealing at 600/sup 0/C is required for removal of all lattice strain. Before loss of surface can oc… more
Date: January 1, 1976
Creator: Gammage, R. B. & Glasson, D. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Whisker growth: a new mechanism for helium blistering of surfaces in complex radiation environments

Description: Implantation of helium concurrent with the generation of large numbers of displaced atoms in surface layers of materials exposed to /sup 252/Cf ..cap alpha..-particles and fission fragments produces a unique form of low temperature surface blistering. The purpose of this paper is to formulate a basis for the whisker-growth mechanism for helium blistering as an aid to the specification of conditions under which the mechanism might apply.
Date: January 1, 1978
Creator: McDonell, W.R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development of the VLS process for SiC whisker growth

Description: Our whisker work involves preparation of whisker samples, whisker characterization, and process scaleup. Sample whiskers are used for composite preparation and for whisker characterization work, while modelling of the production process is itself proving useful. The approach to scaleup recognizes the importance of a full understanding of the process variables. Hence our work in this area is proceeding with studies of the chemistry of the process gases and investigation of the growth mechanism.
Date: January 1, 1984
Creator: Hurley, G. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fabrication of SiC whiskers and composites

Description: The Los Alamos Structural Ceramics Program is a multi-faceted program with an overall objective of producing superior strength and fracture toughness in ceramic bodies for load bearing applications. One phase of the program is pursuing the development of silicon carbide whiskers which are used to prepare ceramic matrix composites. The purpose of this work is to investigate strengthening and toughening mechanisms in ceramic composites. In the following we describe some elements of the whisker de… more
Date: January 1, 1984
Creator: Hurley, G. F.; Shalek, P. D.; Gac, F. D. & Petrovic, J. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Tensile testing of SiC whiskers

Description: The room temperature tensile mechanical properties of SiC whiskers have been examined using a micro-tensile-test apparatus. SiC whiskers exhibit an average tensile strength of 8.4 GPa for a 5 mm tested length, and an average elastic modulus of 581 GPa. These results indicate that SiC whiskers possess significant potential as short-fiber reinforcement elements in ceramic matrix composites.
Date: January 1, 1984
Creator: Petrovic, J. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Silicon carbide whiskers for composites: growth and properties

Description: Silicon carbide (SiC) whiskers have great potential as reinforcements for structural ceramic matrix composites with significantly improved fracture toughness and strength. Such whiskers, synthesized at Los Alamos by a vapor-liquid-solid (VLS) process, are single crystal fibers with diameters in the range of 0.1 to 10 ..mu..m and lengths presently as long as 100 mm. They possess superb mechanical properties, with an average strength of 8.4 GPa (1,220,000 psi) and an average elastic modules of 58… more
Date: January 1, 1985
Creator: Hurley, G. F. & Petrovic, J. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Performance of commercial and research grade SiC whiskers in a borosilicate glass matrix

Description: Dry blending of the whiskers and glass powder yielded composites of satisfactory, but not optimum, homogeneity. The whiskers inhibited composite densification, but this could be remedied by modifying the hot-pressing conditions. All types of whiskers produced improvements in the flexural strength of the composites, with the highest value achieved with the smallest diameter whiskers. The composites displayed a 4- to 5-fold increase in fracture toughness compared to that displayed by the unreinfo… more
Date: January 1, 1986
Creator: Gac, F. D.; Petrovic, J. J.; Milewski, J. V. & Shalek, P. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Assessment of ceramic composites for multimegawatt space nuclear power systems

Description: A calculational thermodynamic equilibrium analysis of the compatibility of ceramic-ceramic composites and a nonequilibrium assessment based on the literature of their use in proposed multimegawatt space nuclear power systems was performed. The five candidate composites included Al/sub 2/O/sub 3/-reinforced Al/sub 2/O/sub 3/, SiC-whisker-toughened Al/sub 2/O/sub 3/, SiC-whisker-toughened Si/sub 3/N/sub 4/, SiC-fiber-reinforced ZrC, and carbon-fiber-reinforced ZrC. The reactor concepts included B… more
Date: December 1, 1986
Creator: Besmann, T.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Whisker reinforced structural ceramics: Progress in the VLS growth and use of long silicon carbide whiskers. [Vapor-liquid-solid]

Description: A VLS (vapor-liquid-solid) whisker growth process, optimized for the production of short (approx.10 mm lengths) SiC whiskers, was modified to produce greater than or equal to 25 mm long whiskers. In conjunction with this modification, a plan was developed for incorporating an artificial-intelligence system to enhance the whisker growth process. An oriented whisker ribbon was produced from the long whiskers, as a step toward the development of a staple whisker yarn.
Date: January 1, 1987
Creator: Gac, F.D.; Shalek, P.D.; Parkinson, W.J.; Edwards, C. & Price, J.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Mechanical characterization of SiC whisker-reinforced MoSi/sub 2/

Description: The mechanical characteristics of an intermetallic matrix with two different reinforcements were studied. The matrix material was MoSi/sub 2/, with either Los Alamos VLS SiC whiskers or Huber VS SiC whiskers. The purpose of the reinforcement was to provide toughening at ambient temperature and strengthening at elevated temperatures. The VLS whiskers greatly improved the yield strength of the matrix at 1200/degree/C, and also increased the room temperature fracture toughness of the matrix. The V… more
Date: January 1, 1988
Creator: Carter, D. H.; Gibbs, W. S. & Petrovic, J. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Microwave sintering of alumina-SiC composites at 2. 45 and 60 GHz

Description: Composites of alumina-10 vol % silicon carbide whiskers were sintered to 70% of theoretical density using both 2.45 and 60 GHz microwave radiation. Further densification was inhibited by formation of a constrained network of whiskers. Alumina-10 vol % silicon carbide platelet composites were sintered to 94% of theoretical density with 2.45 GHz microwaves in less than 20 minutes. 4 refs., 11 figs.
Date: January 1, 1988
Creator: Katz, J. D.; Blake, R. D. & Petrovic, J. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Synthesis and characterization of VLS-derived silicon carbide whiskers

Description: Silicon carbide (SiC) whiskers have great potential, some already realized, in reinforcing ceramic matrix composites to give significant improvements in toughness and strength. Los Alamos has been developing the vapor-liquid-solid (VLS) process to grow single crystal BETA-SiC fibers having relatively few defects and diameters of from 3 to 5 ..mu..m and lengths up to 100 mm. These whiskers have superb mechanical properties-strengths up to 16 GPa (2.3 Msi) and elastic modulus of 580 GPa (84 Msi) … more
Date: January 1, 1988
Creator: Shalek, P. D.; Phillips, D. S.; Christianson, D. E.; Katz, J. D.; Parkinson, W. J. & Petrovic, J. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Theoretical and experimental analysis of the toughening behavior of whisker reinforcement in ceramic matrix composites

Description: Analytical solutions are presented describing the experimentally verified toughening of whisker reinforced ceramics. Clear insights are provided into the interrelationships of whiskers, matrices, and interfaces in the case of strong interfaces with minimized whisker pullout.
Date: January 1, 1988
Creator: Becher, P. F.; Hsueh, C. H.; Angelini, P. & Tiegs, T. N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Application of artificial intelligence control to the vapor-liquid-solid silicon carbide whisker process

Description: Silicon carbide whiskers have excellent mechanical and chemical properties, making them very desirable as a reinforcement for structural ceramic and other composite materials. Los Alamos has developed a laboratory-scale batch process for producing very high quality SiC whiskers by the vapor-liquid-solid (VLS) method which is an active candidate for technology transfer involving significant scale-up. The process, however, involves quite complex chemical/physical and parametric relationships and … more
Date: January 1, 1989
Creator: Shalek, P.D. & Parkinson, W.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Intergranular and interphase boundaries in ceramics

Description: Interfaces are of great importance in both electronic and structural ceramics. The microstructure and microchemistry of interfaces can be studied by transmission electron microscopy, both high resolution and analytical. Examples are taken from both intergranular and interphase boundaries in ceramics. The former include low angle, twin and 90/degree/ boundaries in YBa/sub 2/Cu/sub 3/O/sub 7/ superconductors. Interphase boundaries include epitactic layers of YBa/sub 2/Cu/sub 3/O/sub 7/on SrTiO/su… more
Date: January 1, 1989
Creator: Mitchell, T.E.; Roy, T. & Unal, O.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effects of filament-matrix interfaces on the mechanical properties of SiC-reinforced Si sub 3 N sub 4: A Review

Description: This report summarizes the results of a literature review of the effects of filament-matrix interfaces on the mechanical properties of ceramic composites composed of SiC-filament-reinforced Si{sub 3}N{sub 4}. A general review of the processing and mechanical properties of SiC-filament-reinforced Si{sub 3}N{sub 4} is presented with special emphasis on research pertaining to processing-related effects on filament-matrix interfaces and the resulting effects of these interfaces on fracture behavior… more
Date: September 1, 1989
Creator: Schilling, C.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Aluminum nitride-silicon carbide whisker composites: Processing, properties, and microstructural stability

Description: Aluminum nitride -- silicon carbide whisker composites with up to 20 vol % whiskers were fabricated by pressureless sintering (1750{degree}--1800{degree}C) and by hot-pressing (1700{degree}--1800{degree}C). Silicon carbide whiskers were found to degrade depending on the type of protective powder bed used during sintering. Whiskers were found to degraded in high oxygen containing samples by reaction with sintering additives. Whisker degradation was also due to the formation of silicon carbide --… more
Date: January 1, 1990
Creator: Cross, Michael Thomas
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Ceramic fabrication R D

Description: This project is separated into three tasks. The first task is a design and modeling effort to be carried out by MSE, Inc. The purpose of this task is to develop and analyze designs for various cohesive ceramic fabrication (CCF) components. This quarter, the advanced molybdenum disicilide MHD electrode design was essentially completed. Final refinements will be made after molybdenum disilicide processing results are available and the final layer compositions are established. Work involving whisk… more
Date: January 1, 1990
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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