Method of producing high density silicon nitride sintered bodies.

摘要

A high density silicon nitride sintered body is obtained by preliminarily sintering a shaped body comprised of silicon nitride powder of at least 90% alpha phase and Y2O3 and/or Al2O3 as sintering aid before hot isostatic pressing treatment using a glass capsule. The preliminary sintering is selected to achieve a silicon nitride beta -phase forming ratio of 20-60%.