Application Of Boron Nitride Ceramics

Boron nitride can be used to manufacture crucibles for melting semiconductors and high-temperature containers for metallurgy, semiconductor heat dissipation insulation parts, high-temperature bearings, thermocouple sleeves and glass forming molds, etc.
The boron nitride usually produced is a graphite-type structure, commonly known as white graphite. The other is a diamond-type, similar to the principle of graphite turning into diamond. Graphite-type boron nitride can be transformed into diamond-type boron nitride under high temperature (1800℃) and high pressure (800Mpa). The B-N bond length (156pm) in this boron nitride is similar to the C-C bond length (154pm) of diamond, and the density is also similar to that of diamond. Its hardness is comparable to that of diamond, but its heat resistance is better than that of diamond. It is a new type of high-temperature resistant superhard material used to make drill bits, grinding tools and cutting tools.