| 摘要 |
PROBLEM TO BE SOLVED: To provide a surface-coated cutting tool having a hard coated layer that exhibits excellent chipping resistance in interrupted heavy-duty cutting. SOLUTION: In the surface-coated cutting tool, a hard coated layer including a CrAIN layer having an average layer thickness of 0.2-2μm (when its composition formula is represented by (Cr<SB>1-X</SB>Al<SB>X</SB>)N, X is preferably 0.10-0.70 by atomic ratio.) is formed on a tool base surface of WC-based cemented carbide by vapor deposition. In the surface-coated cutting tool, the CrAIN layer has a height equal to the average layer thickness, and comprises oblong flat plate-shaped CrAIN crystal grains grown perpendicularly to the tool base surface. When a crystal grain structure in a horizontal cross-section at the depth of 0.1μm from the surface of the CrAIN layer is observed, the area ratio of the oblong flat plate-shaped CrAIN crystal grains each having a short side of 5-100 nm and an aspect ratio of 3 or more is 30% or more of the total horizontal cross-sectional area. COPYRIGHT: (C)2011,JPO&INPIT
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