Oxide ceramics include alumina, zirconia, silica, aluminum silicate, magnesia and other metal oxide based materials. They are non-metallic, inorganic compounds that include oxygen, carbon, or nitrogen. Oxide ceramics have high melting points, low wear resistance, and a wide range of electrical properties. The minerals used to make these ceramic materials are crushed or ground into a fine powder that is purified by adding it to a solution and allowing a chemical precipitate to form. The precipitate is then separated from the solution and heated to form a highly pure powder. After purification, small amounts of wax are added to bind the ceramic powder. Plastics may also be added to provide pliability. The powder can then be shaped into different objects by various molding processes such as slip casting, pressure casting, injection molding, and extrusion. After oxide ceramic materials are molded, they are heated in a process known as densification to strengthen the material.
Oxide ceramics vary by maximum use temperature, thermal conductivity, modulus of rupture, modulus of elasticity, electrical resistivity, average crystal size, density, and purity. The maximum use temperature is the highest temperature to which oxide ceramic materials can be exposed without degradation. Thermal conductivity is the linear heat transfer per unit area for a given applied temperature gradient. The modulus of rupture (MOR) or cross-break strength is the maximum flexural strength that oxide ceramics can withstand before failure or fracture occurs. Young’s modulus or the modulus of elasticity is a material constant that indicates the variation of strain produced under an applied tensile load. Average crystal size measures the individual grains or crystals within the microstructure of a polycrystalline material. Density is the mass per unit of area. Purity is the percentage, by weight, of major components.
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Ceramic - Wikipedia, the free encyclopedia Clay-based ceramics are described in the article on pottery. Oxides: Alumina, zirconia Non-oxides: Carbides, borides, nitrides, silicides |
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Oxide Ceramics – Web Listings Oxide Ceramics (Alumina, Zirconia, Silicates) Information on ... Oxide ceramics include alumina, zirconia, silica, aluminum silicate, magnesia and See Business.com, Inc. Information |

