Cermet is the name given to a composite material made of both ceramic and metallic components. Uses for these composite materials include, among other things, various lighting applications. Cermet pins are made of aluminum oxide as the ceramic component and molybdenum or platinum as the metallic component.
This composite material has a coefficient of expansion similar to pure aluminum oxide, good electrical conductivity and a high corrosion resistance, e.g. to various halogenides found in the gas filling of metal halogen lamps. These properties make cermet a preferred material for these lamps, where they are exposed to a high thermal load in addition to the chemical influences.
