| 摘要 |
PURPOSE:To obtain a coated sintered hard alloy coated with a thin layer with superior wear resistance by forming layers of carbides, carbonitrides and nitrides of one or more kinds of metals selected from the IVa, Va and VIa group metals on the surface of a sintered hard alloy in succession from the inside, followed by heat treatment at a predetermined temp. CONSTITUTION:A sintered hard alloy such as ISO P-30 contg. 0.03% free C precipitated is coated with the above carbides such as titanium carbide, the above carbonitrides such as titanium carbonitride and the above nitrides such as titanium nitride by chemical vapor deposition in succession. The coated alloy is then heat treated at 950-1050 deg.C for 1-5 hr in a carbide-forming atmosphere, e.g. based on CH4 or a mixt. of H2 and CH4 gas to make the C distribution in the alloy uniform. Thus, a coated sintered hard alloy is obtd. having remarkably enhanced performance as a cutting tool. |
