SETTER FOR HEAT TREATMENT

摘要

PURPOSE:To enable to form a heat treatment setter having excellent oxidation resistance, creep resistance and strength and reduced in the weight thereof by employing a calcined porous silicon carbide obtained by molding and calcining a raw material powder comprising alpha-type silicon carbide fine particles and alpha-type silicon carbide coarse particles in a specific ratio. CONSTITUTION:A raw material powder comprising >=20wt.% of alpha-type silicon carbide fine particles having particle sizes of <=1mum, the remaining amount of alpha-type silicon carbide coarse particles having particle sizes of 1-20mum and <=5wt.% of inevitable impurities is molded and calcined to form a porous silicon carbide calcined product. The calcination process is carried out in a vacuum or inert atmosphere at a temperature of approximately 1600-2200 deg.C. The above- mentioned setter for heat treatment may be produced only from the formed silicon carbide calcined product or by using the silicon carbide calcined product as an aggregate. For example, an alumina coating layer is formed on the surface of the silicon carbide calcined product to provide the setter.