Carbon silicon carbide

Silicon Carbide. Silicon carbide is made by the electrofusion of silica sand and carbon. Silicon carbide is hard, abrasion resistant, and has a high thermal conductivity. It is relatively stable but has a tendency to oxidize above 1400°C. The silica thus formed affords some protection against further oxidation (see Carbides). 

Two principal mechanisms that may be responsible for mass loss from red giants are considered shock wave-driven winds and radiatively (dust)-dr iven winds. Effect of the periodic shocks accompanying nonlinear oscillations of red giants is most prominent in the outer layers of the stellar atmosphere where shocks are able not only to expel gas but also increase gas density so that some molecular components become supersaturated. In 0-rich stars the most abundant condensible species are silicon monoxide and iron, whereas in C-rich stars these are carbon, silicon carbide and iron. 

Chemical vapor infiltration (CVI) is widely used in advanced composites manufacturing to deposit carbon, silicon carbide, boron nitride and other refractory materials within porous fiber preforms. " Because vapor phase reactants are deposited on solid fiber surfaces, CVI is clearly a special case of chemical vapor deposition (CVD). The distinguishing feature of CVI is that reactant gases are intended to infiltrate a permeable medium, in part at least, prior to... 

A compound of siUcon and carbon, silicon carbide, is a major industrial abrasive. Its common name is carborundum. People who have a home workshop use silicon carbide sticks to sharpen their tools. 

Pyrolytic Carbon Silicon Carbide Porous Carbon Buffer Uranium Oxycarbide... 

JOINING AND INTEGRATION OF ADVANCED CARBON-CARBON AND CARBON-SILICON CARBIDE COMPOSITES TO METALLIC SYSTEMS... 

Joining and Integration of Carbon-Carbon and Carbon-Silicon Carbide Composites... 

The traditional TPS for launcher fairings and re-entry capsules consists of an external ablative insulation, fixed or bonded onto a metallic primary structure. Ablative materials are based on thermosets (phenolic and epoxy resins) or elastomers (ethylene-propylene and silicone rubbers) usually filled and reinforced with cork, cotton, glass, silica, quartz, carbon, silicon carbide, nylon and aramid in the form of powders, fibres, fabrics and felt (Table 2). 

Long-term oxidation protection requires multilayer protection coatings, where the car-bon/carbon or carbon/silicon carbide composite is protected for example with SiC layers and additional self-healing glass forming layers, based on oxides like mullite, alumina... 

Composites - preforms can be infiltrated using CVD techniques to produce ceramic matrix composites such as carbon-carbon, carbon-silicon carbide, and silicon carbide-silicon carbide composites. This process is sometimes called chemical vapor infiltration or CVI. 

Structures have been produced that utilize all of the above materials and even some other binders. Found in this group of materials are carbon fibers infiltrated and held together with pyrolytic carbon, silicon carbide, glassy carbon, FIFE, methyl methacrylate, epoxies, and petroleum pitches as well as combinations thereof. The structures may contain randomly oriented chopped fibers or long filaments oriented in random, 2, 3 and n dimensions. 

The technology of manufacturing sheath/core bicomponent boron/ tungsten, boron/carbon, silicon carbide/tungsten, and silicon carbide/ carbon fibers is 40 years old and the relationships between process variables, structures, and properties have been authoritatively described in important review articles. One article deals mainly with their preparation [33] another correlates process variables with structures [34], and one explores potential correlations between structures and properties [30]. 

Xu Y, ZJiang L, Three-dimensional carbon/silicon carbide composites prepared by chemical vapor infiltration, J Am Ceramic Soc, 80(7), 1897-1900, 1997. 

Figure 1.51 illustrates the results of a bend test of five specimens of three-dimensional carbon-silicon carbide compared with tension tests (Fig. 1.52) on the same material. The results of the bend test are similar to stress-strain curves however, the stress is plotted versus deflection, rather than versus strain. The results of these bend and tension tests appear in Tables 1.6 and 1.7. 

Pyrolytic carbon Silicon carbide Porous carbon buffer Uranium oxycarbide... 

IC Silicon Carbide. Abbreviation for Impregnated-Carbon Silicon Carbide it contains free carbon and silicon and the bulk density is comparatively low (2.60). ICP. Inductively Coupled Plasma. An emission spectrometry technique for the chemical analysis of ceramics. 

Pyrolithic carbon Silicon carbide barrier coating Inner pyrolithic carbon -Porous carbon buffer... 

The 6 cm spherical fuel elements of HTR-10 are made of TRISO type coated particles (CP) and graphite matrix. One CP consists of a UO2 kernel with a diameter of 0.5 mm, which is successively coated with layers of low density pyrolytical carbon, inner high density isotropic pyrolytical carbon, silicon carbide and outer high density isotropic pyrolytical carbon, with thicknesses of respectively 90, 40, 35 and 40 pm. About 8,300 coated particles are dispersed in the graphite matrix, which is 5 cm in diameter, to form the fuel zone of a fuel... 

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