Use of melamine in the nitridation of aluminum oxide to aluminum nitride

Abstract

By using melamine as a nitridizing reagent, aluminum nitride (AlN) powders were prepared from δ- and α-alumina (Al₂O₃) powders which had not been mixed with carbon. The hydrogen cyanide (HCN) formed by thermal decomposition of melamine was involved in the nitridation of Al₂O₃ to AlN. The nitridation process of alumina to AlN was monitored by powder X-ray diffraction patterns and ²⁷Al magic-angle spinning nuclear magnetic resonance spectroscopy. δ-Al₂O₃ began to be converted to AlN at 1050°C without δ-α alumina transformation. The nitridation rate of δ-Al₂O₃ was much higher than that of α-Al₂O₃.