| 摘要 |
PURPOSE:To improve machinability in said tools having high bonding force with a base metal excellent in wear resistance by a method wherein on the base metal the inner layer is coated with a specific coating film and the outer layer is composed of a coating film of Al-carbide of a specific weight. CONSTITUTION:On a tool base metal composed of a super hard alloy, a cermet or a high speed steel is formed a coating layer composed of a single material or two or more composite materials selected from groups composed of a carbide, a nitride, an oxide, which comprise Ti, Zr, Hf, Ta and W as the inner layer. And, this is coated at a thickness of 0.5-0.10mum by a single layer or two or more layers on the base metal. The outer layer forms a coating film which is composed mainly of Al- oxide or nitric oxide and wherein 0.1-10% by weight of it is Al-carbide. The layer is of a thickness of 0.5-5mum. Thus, by increasing hardness of the inner layer itself and containing Al-carbide of 0.1-10% by weight in the outer layer, the bonding force with the inner layer is elevated and machinability also can be improved. |
