Member for use in contact with molten nonferrous metals

摘要

The member for use in contact with molten nonferrous metals comprises a substrate made of an Fe-base alloy and a dense surface layer composed of an oxide or oxynitride. The oxide or oxynitride surface layer is formed by preheating the substrate in a non-oxidizing atmosphere such as a nitrogen gas, and then heat-treating it in an oxidizing or oxynitriding atmosphere containing steam such as a mixture of the air and an overheated steam, or in an atmosphere generating oxygen and steam such as a mixed gas comprising a hydrogen gas and a carbon dioxide gas, at a temperature of 650 DEG C and 1100 DEG C.