White Graphite Crystal Form

(1) Hexagonal boron nitride (similar to graphite, also known as graphite boron nitride, white graphite). The relative density is 2.25. Mohs hardness is about 2. It is a white powder that melts at about 3000°C under high pressure. It has good electrical insulation, thermal conductivity, corrosion resistance and good lubricity. It has good chemical stability and does not react with water, acid or alkali at room temperature. Boil with water and slowly hydrolyze to generate boric acid and ammonia. Reacts with hot concentrated or molten alkali and hot chlorine. Can withstand high temperatures of 2000°C. Has a strong ability to attract electrons. It can be obtained by heating borax and ammonium chloride in ammonia gas flow.

(2) Cubic boron nitride (diamond type). It is black or brown granular crystals. The relative density is 3.48. The melting point is 3000°C. The hardness is comparable to diamond. The stability is better than diamond at high temperature. It can be directly synthesized with boron and nitrogen under high temperature and high pressure conditions.