| 摘要 |
PROBLEM TO BE SOLVED: To provide a surface coated cutting tool with a hard coating layer which exhibits excellent chipping resistance performance in a high-speed intermittent cutting process of alloy steel or the like.SOLUTION: A surface coated cutting tool includes a base body comprising a WC-based cemented carbide, TiCN-based cermet and a cBN-based ultrahigh-pressure sintered body, and the surface of the base body is coated with at least a hard coating layer which is a compound layer produced by a chemical deposition method using a gas containing, for example, Al(CH)as a reactant gas component. The compound layer is composed of a crystal grain structure of (Ti-AI) (CYN) having a cubic-structure (wherein X, Y denote an atom ratio, and are in the range of 0.60≤X≤0.90, 0.0005≤Y≤0.005) and an amorphous phase structure. Further, the compound layer forms a grain width distribution where an average grain width gradually increases as proceeding from a base body side to a surface layer side of the compound layer. Besides, a content ratio of Al in the compound layer includes such a composition grading structure as to gradually increase as proceeding from the base body side to the surface layer side of the compound layer. |
