Mechanically Stimulated Low-Temperature Synthesis of Aluminium Nitride
Synthesis method is based on grinding coarse aluminium powder in the planetary centrifugal mill in the presence of a surface-active organic substance that promotes a decrease in the size of aluminium particles and coats the resulting products with a film that is impermeable for oxygen. The synthesis is carried out in the flow of high-purity nitrogen. At a temperature of 300–400 °C, the organic film is evaporated from the precursor particles, aluminium surface active toward nitriding shows up, and reaction takes place at a temperature about 750 °C. The yield of the product is about 100 %, its oxygen content is less than 0.6 mass % (the detection limit for the method used). Because of low temperatures, the resulting powder is weakly agglomerated. Particle size varies within the range 350–500 nm.