| 摘要 |
PURPOSE:To raise wear resistance and lubricity of the surface of alloy steels by the procedure in which a nitride layer, a carburized layer, etc., is formed on the surface of alloy steel by a glow discharge in a gas containing N2 or/and C, and then covered with a formed film having a solid lubricating action. CONSTITUTION:An alloy steel whose surface is coated with a lubricant, e.g., mold, tool, sliding part, etc., is put in an air-tight vessel and then evacuated. Then, a gas containing N2 or C is filled in the vessel and its pressure is regulated to 10<-1>- 10 Torr and then a 300-2000V DC voltage is applied across the vessel as anode and the alloy steel as cathode to cause a glow discharge to take place, whereupon ionized N or N and C collide with the surface of the steel to destroy oxides formed on the surface and thereby to accelerate the diffusion and impregnation of N or N and C. Then, the surface of the alloy steel thus treated is covered with a film of a phosphate or an oxalate and then with covered with a film of a sodium soap, e.g., sodium stearate, etc., or a fat. Thus, biting, etc., of tool, etc., made of alloy steels used in sliding parts or plastic processing molds can be prevented. |
