CERAMICS, AND CARBON-GRAPHITE

The various sections in the book cover selected categories of corrosion resistant materials, such as synthetic resins and polymers rubbers and elastomers cements, mortars, and asphalt ferrous alloys nonferrous metals and alloys and glass, ceramics, and carbon-graphite. A separate section presents a group of 13 tables which compare the anticorrosive merits of a cross section of commercial engineering and construction materials essential to industry. The tables in the book represent selections taken directly from manufacturers literature made at no cost to, nor influence from, the makers or distributors of these materials. 

Development of highly durable catalyst supports, such as carbon with more graphitic components, ceramic, and carbon-ceramic composite materials, which could survive in a high-temperature enviromnent. 

Refractories, Glass, Ceramic Materials Carbon and Graphite Products," ASTM Annual Book ofASTM Standards, Vol. 15.01, ASTM, Philadelphia, Pa., 1992. 

A hard, mst-resistant shaft of at least 0.25 micrometer finish is usually required. Common shaft surfaces are hardened tool steel, chrome plate, high strength bronze, and carbide and ceramic overlays. Test results over a broad speed range from 0.05 to 47 m/s (10 to 9200 fpm) iadicate that a coefficient of friction of 0.16—0.20 and a wear factor of 14 X 10 m /N(70x 10 ° in. min/ft-lb-h) are typical for dry operation of weU appHed grades of carbon—graphite (29). 

Historically, polymer-matrix composite materials such as boron-epoxy and graphite-epoxy first found favor in applications, followed by metal-matrix materials such as boron-aluminum. Ceramic-matrix and carbon-matrix materials are still under development at this writing, but carbon-matrix materials have been applied in the relatively limited areas of reentry vehicle nosetips, rocket nozzles, and the Space Shuttle since the early 1970s. 

Acid resistant metals and alloys) pp 1534-36(Acid resistant carbon, graphite, cement, mortar, putty, ceramics and plastics)... 

Si3N4 ceramics have been, and sometimes still are, sintered in a powder bed to prevent the decomposition and interaction with carbon and/or graphite... 

This chapter describes the preparation and examination of ceramic matrix composites realized by the addition of different carbon polymorphs (carbon black nanograins, graphite micrograins, carbon fibers and carbon nanotubes) to silicon nitride matrices. In the following sections, structural, morphological and mechanical characteristics of carbon-containing silicon nitride ceramics are presented. 

Electrode materials Pt. platinum PG. pyrographite AC, active carbon GC. glasslike carbon CF. carbon fiber. CCEs, ceramic carbon electrodes CPE. carbon (graphite) paste electrode Soim e-. Refs. 12, 201. and 206-221... 

Advanced waste form work is also being carried out in the Ceramics and Graphite Section at PNL, where high temperature gas-cooled reactor fuel technology is applied to waste solidification. Waste particles are coated with pyrolytic carbon followed by a cover coat of silicon carbide. These coated particles would then be placed in a matrix of inert material contained in a canister of yet another material. 

Carbide powder is manufaetured by carburization of the metal, metal oxide or metal hydride with nuclear-pure graphite at ca. 2000°C. Carbide powder pellets (see Section 5.5.5.1.5) or beads up to 0.6 mm in diameter are formed and sintered using ceramic process technology. Reaction sintering is commonly used for the manufacture of uranium earbide fuel beads, in whieh uranium oxide and carbon are first mixed then annealed to form the carbide and then are sintered to 90 to 95% of the theoretical density. An... 

Ceramic materials, graphite and carbon bricks which are high temperature resistant surround the reactor core. 

A) Spillover to chemically inert supports, including the ceramic oxides (AI2O3, Si02, MgO etc), acidic oxides (including zeolites), and carbon (activated charcoal, graphite etc). 

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