α ALUMINA SINTERED BODY FOR PRODUCTION OF SAPPHIRE SINGLE CRYSTAL

摘要

PURPOSE: Anαalumina sintered body for production of sapphire single crystal is provided to acquire high quality sapphire monocrystal by using a compact having a high mechanical strength. CONSTITUTION: A relative density of monocrystal of sapphire is over 60%. The closed porosity of the sapphire monocrystal is less than 10%. The purity of the sapphire monocrystal is more than 99.99 weight%. Each content of Si, Na, Ca, Fe, Cu, and Mg is less than 10ppm. A volume of the sapphire monocrystal is more than 1cm^3.