Abstract
AlN granules, containing 5mass% Y2O3, were sintered at various conditions in a nitrogen flowing atmosphere to investigate its sinterability. The resulting microstructures were characterized as well. AlN granules sintered at 1850°C for 15min were densified to a relative density of 98%. In the granules sintered at 1600°C for 15 min, AlYO3 and Al2Y4O9 secondary phases were identified by XRD, due to the reaction between Y2O3 additive and Al2O3 impurity from AlN granules. Y2O3 was formed in the granules sintered at 1850°C for longer than 3h by the reduction reaction of AlYO3 and Al2Y4O9 with the reducing nitrogen atmosphere. Oxygen content of the granules sintered at 1850°C for 24h decreased to one third of that of dewaxed granules.
