Polycrystalline transparent spinel sintered body and a method for producing the same

摘要

Polycrystalline spinel sintered body consisting mainly of Al2O3 and MgO in a molar ratio of Al2O3/MgO of ranging from 0.52/0.48 to 0.70/0.30 and containing 0.001-0.1% by weight of LiF has a high in-line transmission. The sintered body can be obtained by calcining a powdery mixture of Al2O3 and MgO in a specifically limited molar ratio, molding the calcined mixture into a shaped article together with a specifically limited amount of LiF, and firing the shaped article under a specifically limited temperature condition.