SURFACE-COATED CUTTING TOOL HAVING HARD COATING LAYER EXERTING EXCELLENT CHIPPING RESISTANCE

Japanese Patent JP2020104209

A

To provide a cutting tool exerting excellent chipping resistance over a long period even when the tool is applied to high-speed intermittent cutting of alloy steels or high-carbon steels.SOLUTION: A cutting tool in this invention has a hard coating layer (Ti1-XAlX)(CYN1-Y) of NaCl type face-centered cubic structure having an average layer thickness of 1.0 to 20.0 μm and 80 area% or more. The coating layer has an average grain width W of 0.10 to 2.00 μm and an average aspect ratio A of 2.0 to 10.0; Xavg of each section divided at 0.5 μm interval satisfies 0.60≤Xavg≤0.95; Yavg of the whole layer satisfies 0.000≤Yavg≤0.005; and Xavg increases in a tool surface direction. The cutting tool satisfies Xαavg≤0.90:Xαavg+0.10≤Xβavg≤1.00, and 0.90