Chemical Properties
dark gray brittle solid; cub, a=0.46983 nm; it is not a fixed stoichiometric compound; hard, high melting carbide used in UC-fueled reactors; enthalpy of fusion 79.4kJ/mol; hardness 8+ Mohs; used as a hot pressed crucible to melt metals such as bismuth, cadmium, lead, tin and high melting point oxides such as ZrO2, and as a 99.5% pure sputtering target to produce wear-resistant and other films [KIR84] [HAW93] [CER91] [JAN71]
Chemical Properties
Zirconium carbide , nominally ZrC, is a dark gray brittle solid. It is made typically by a carbothermic reduction of zirconium oxide in a induction-heated vacuum furnace. Alternative production methods, especially for deposition on a substrate, consist of vapor-phase reaction of a volatile zirconium halide, usually ZrCl4, with a hydrocarbon in a hydrogen atmosphere at 900–1400 °C (1652–2552 °F).
Physical properties
Gray metallic solid; cubic structure; very hard, hardness > 8.0 Mohs; density 6.73 g/cm
3; melts at 3,532°C; insoluble in water; slightly soluble in concentrated sulfuric acid; soluble in hydrofluoric acid and oxidizing acids, such as nitric and perchloric acids; attacked by oxidizers.
Physical properties
Dark gray brittle solid, soluble
in HF solutions containing
nitrate or peroxide ions. UC-nuclear power reactor, crucible
container for handling molten
metals such as Bi, Cd, Pb, Sn,
Rb, and molten zirconia ZrO
2. Corroded by liquid metals Mg,
Al, Si, V, Nb, Ta, Cr, Mo, Mn, Fe,
Co, Ni, and Zn. In air oxidizes
rapidly above 500°C. Maximum
operating temperature of 2350°C
in helium.
Uses
Zirconium carbide is a refractory material. It is used in making incandescent filaments, high temperature electrical conductors, and cutting tool components.
Preparation
Zirconium carbide is prepared by heating a mixture of zirconium oxide and coke in an arc furnace.
