Super-Heat™ 502-676 magnesium oxide (MgO) ceramic crucibles are available for use in the processing of ultrahigh-temperature refractory metals, slags and superconductor compounds to 4000°F. Applications include the processing of nickel-based superalloys, plutonium and uranium compounds and beta-alumina. Super-Heat™ 502-676 MgO is a high-density, fine grain microstructure with an open porosity of less than 1%. This ceramic is an ideal alternative to alumina because it exhibits better chemical resistance and is inert to metals, slags and superconductor compounds. It is available in both stock and custom shapes up to 7 inches in diameter x 12 inches in length with a maximum wall thickness of 0.2 inches.