Features of Carbothermal Synthesis of Aluminum Nitride under Nitrogen Pressure

Abstract

Aluminum nitride is synthesized by the carbothermal method from a mixture of aluminum oxide and carbon black under a nitrogen pressure of 0.2-0.3 MPa at 1800-1900°C and with an isothermal soaking time of 3 h. The best results are obtained with synthesis at 1800°C and a nitrogen pressure of 0.3 MPa from a charge of stoichiometric composition. Powder with an AlN content up to 99 mass% consists of isometric grains with a narrow size range (2-6 μm). Introduction of lithium carbonate into the original mixture worsens the results.