Morphology of Platelike Abnormal Grains in Liquid‐Phase‐Sintered Alumina

Abstract

The microstructural features of platelike grains in liquid‐phase‐sintered Al 2 O 3 were investigated. The flat boundaries of platelike grains wetted with a liquid phase were basal planes. After impingement of platelike grains, flat boundaries progressively changed to curved boundaries which consisted of both basal and rhombohedral planes as microscopic facets. Second‐phase particles were observed for most doped samples. Small‐angle subgrain boundaries inside platelike grains were also observed.