| 摘要 |
A surface-coated cutting tool includes a tool substrate made of tungsten carbide-based cemented carbide or titanium carbonitride-based cermet; and a hard coating layer, which is formed by vapor-depositing in order, a lower layer (a), an intermediate layer (b), and an upper layer (c) on the surface of the tool substrate. The lower layer (a) is a Ti compound layer composed of one or more of a titanium carbide layer, a titanium nitride layer, a titanium carbonitride layer, a titanium carboxide layer, and a titanium oxycarbonitride layer, and having a total mean layer thickness of 3 to 20 µm, the intermediate layer (b) is an aluminum oxide layer having a mean layer thickness of 1 to 5 µm, and having an ±-type crystal structure in a chemically vapor-deposited state, and the upper layer (c) is an aluminum oxide layer having a mean layer thickness of 2 to 15 µm, and containing one or more kinds of elements selected from a group consisting of Ti, Y, Zr, Cr, and B having an ±-type crystal structure in a chemically vapor-deposited state. |
