Alumina ceramic articles having cubic spinel on surfaces and methods for preparing alumina ceramic articles and for sintering

摘要: An alumina ceramic article and a method for preparing the article. The comprises steps of: (1) Compacting mixture of first concentration particulate aluminum oxide sufficient to prevent retention zirconium alloy particles in surface predominantly tetragonal crystal structure second alloy. is secondary selected from group consisting MgO, CaO, Y2 O3, Sc2 CeO2, rare earth oxides having generally about 0.5 5 mole percent 0.1 1 15 7.0 or relative total compacting results formation blank. (2) Providing contact between blank dopant oxide. (3) Sintering with