Boron nitride is used in the manufacturing of crucibles for semiconductor melting, high-temperature containers for metallurgy, semiconductor heat-sinking insulating components, high-temperature bearings, thermocouple sleeves, and glass forming molds, among others.
Typically produced boron nitride is in a graphite-like structure, commonly known as white graphite. Another form is the diamond-like structure, similar to the transformation of graphite into diamond. Graphite-type boron nitride can be converted into diamond-like boron nitride under high temperatures (1800℃) and high pressures (800Mpa). This boron nitride has a B-N bond length (156pm) similar to diamond's C-C bond length (154pm), and its density is also close to that of diamond. Its hardness is comparable to diamond, and it has better thermal resistance, making it a new ultra-hard material for high-temperature applications. It is used in the manufacturing of drill bits, abrasive tools, and cutting tools.
