| 摘要 |
PURPOSE:To form coating films of an excellent adhesive state by treating a superhard alloy tool under specific conditions in a specific vacuum before coating stage and coating the same without returning the same again into the atmosphere. CONSTITUTION:A superhard alloy is put for >=5min in a vacuum atmosphere of <=5X10<-1>torr at >=1,100 deg.C just prior to coating stage, and carbides, nitrides, oxides, and borides of IVa, Va, IVa groups and compds. and mixtures of >=1 kind thereof as well as >=1 kind of Al2O3, AlN, SiC, Si3N4, SiO2, etc. are coated by CVD or the like on the surface thereof without returning the same again into the atmosphere. Much better results are obtained if the heat treatment conditions are >=1,200 deg.C and in <=10<-1>torr vacuum. Machining properties are improved by putting a small amt of. a reducing gas such as H2 or CO into this atmosphere. |
