Structure and Properties of Aluminum Nitride and AlON Ceramics

A brief review of aluminum nitride and AlON ceramics is presented in the context of the pseudobinary aluminum nitride-aluminum oxide phase equilibrium system. AlON is the name applied to the nitrogen stabilized cubic spinel in this system, with a composition centered at 35.7 mole-percent AlN. First, the phase equilibria and crystal chemistry of these phases are presented, focusing on a constant anion oxynitride spinel model and the various phases, including polytypoids, in this system. Then, a brief summary is given on the processing and microstructures of AlN and AlON, with comparisons to other microstructures in this system. Finally, selected properties of AlN and AlON are discussed and tabulated, with special reference to alumina. A comprehensive reference list is given.