The reaction sintering and microstructural development of alumina with additions of 1-25 mol% AlN have been investigated by heating under 1-atm nitrogen gas at 1600-1800 degreesC. Sintering Al2O3 with 1 mol% AlN addition at 1750 degreesC, resulted in a ceramic with close to theoretical density of alpha -Al2O3 (3.98 g/cm(3)). For the different compositions, the sintered densities decreased with increasing AlN content. This trend was attributed to the presence of secondary phases such as AlON(9Al(2)O(3).5AlN) and phi (5Al(2)O(3).AlN) formed by reacting Al2O3 with AlN. For a given AIN addition, densification increased with sintering temperature, due to Al2O3 and/or AlON grain growth control. The stability of the individual crystalline phases depends on both sintering temperature and batch composition. (C) 2001 Published by Elsevier Science Ltd.
|Number of pages||9|
|Journal||Journal of the European Ceramic Society|
|Publication status||Published - 2001|