| 摘要 |
PURPOSE:To obtain a siliceous nitride sintered member having improved corrosion resistance without impairing mechanical characteristic by removing a part of a surface layer formed on the surface of the siliceous nitride sintered member by machining not to damage the part of the surface layer. CONSTITUTION:A siliceous nitride sintered member is machined by grinding with a diamond grinder of about #140 count to form a surface layer having about 50mum layer changed in qualities. Then the surface layer is abraded dividedly at two stages by primary adrasion using <=50mum grinder particles and by secondary abrasion using one or more of <=15mum grinder particles and Fe2O3 powder. Then, one or more parts of the surface layer are removed up to 20mum depth from the machined surface or the surface layer part is removed up to a depth at which compression stress is at least <=50MPa. Or, the surface layer is heat-treated in a nonoxidizing atmosphere at <=1,550 deg.C to produce a siliceous nitride sintered member. |
