| 摘要 |
PURPOSE:To permit the exact discernment of used or unused cutting blades by providing a layer containing specific amounts of TiC, N, and O on the surface of a throw-away tip cutting blade consisting of a hard alloy base metal and alpha- alumina layer formed on the base metal through a layer of a specific metal carbide, nitride, or oxide. CONSTITUTION:The surface of a hard alloy base metal is coated with a 1-20 micron thickness of a solid solution layer composed of one or more of the carbides, nitrides, and oxides of the metals of the 4a, 5a, and 6a groups, and then with a 0.2-5 micron thickness of alpha-alumina layer. The coated hard throw-away tipped cutting blade thus obtained is further coated with a 0.01-0.5 micron thickness of a layer of TiCxNyOz(x<=0.3, y<=1.0, z<=0.1, and x+y+z=1.0), the color which is of a bright yellowish to orange color before use but turns black at high temperatures resulting from cutting work. The third coat enables one to discern the used or unused blades even inside a machine tool under insufficient illumination. |
