METHOD OF PREPARING ALUMINUM NITRIDE POWDER THROUGH ATMOSPHERE CONTROLLED CARBON-THERMAL REDUCTION

摘要

A method of preparing aluminum nitride powder through atmosphere controlled carbon-thermal reduction. It relates to a chemical dilution method to wrap the carbon material evenly around the surface of γ-aluminum oxide (gamma phase-aluminum oxide). The method includes the following processes of: material mixing, carbonization, carbon-thermal reduction, and de-carbonization. Wherein, γ-aluminum oxide and phenolic resin are mixed to form a solution, and after the solution is baked and dried into powder, it is carbonized under nitridation atmosphere in high temperature. Then, carbon-thermal reduction is performed in a temperature of 1400° C.˜1700° C. Finally, de-carbonized is performed in air. In the process of carbon-thermal reduction, ammonia gas and hydrogen gas are added to regulate the reacting atmosphere. Also, urea is added to increase the nitridation reaction of aluminum.

主权项

1. A method of preparing aluminum nitride powder through atmosphere controlled carbon-thermal reduction, comprising following steps:
(A) providing a γ-aluminum oxide (gamma phase-aluminum oxide); (B) providing a phenolic resin; (C) pouring in chemical solution to mix with the γ-aluminum oxide and the phenolic resin, to stir them evenly, and to make phenolic resin dissolve into forming a solution; (D) putting the solution into a bake oven, to bake and dry it into powder; (E) placing the powder into a high temperature furnace in a nitridation atmosphere to perform carbonization, to form into powder; (F) grinding the carbonized powder to particles of diameter less than 2 mm; (G) adding additive into the grinded powder, to put it into the high temperature furnace of nitridation atmosphere to perform nitridation; and (H) placing the nitridated powder in air or an oxygen gas atmosphere to perform de-carbonization, to form into aluminum nitride powder.