CPC B23B 27/145 (2013.01) [B23B 27/20 (2013.01); C01B 32/25 (2017.08); C23C 16/27 (2013.01); C30B 29/04 (2013.01); B23B 2200/201 (2013.01)] | 7 Claims |
1. A turning tool used for turning, the turning tool comprising: a holder portion; and a cutting edge portion fixed to the holder portion, wherein
the cutting edge portion is composed of a synthetic single-crystal diamond,
the synthetic single-crystal diamond is a CVD single-crystal diamond,
the CVD single-crystal diamond includes more than or equal to 1 ppm and less than or equal to 100 ppm of hydrogen,
the cutting edge portion includes a rake face, a flank face, and a cutting edge disposed at a crossing portion at which the rake face and the flank face cross each other, and the cutting edge portion has a nose curvature having a curvature radius of more than or equal to 0.1 mm and less than or equal to 1.2 mm, and
the nose curvature satisfies at least one of
a condition that a direction of a line of intersection between the rake face and a bisecting cross section of a vertex angle of the nose curvature is within ±10° relative to a <110> direction of the synthetic single-crystal diamond, and
a condition that the direction of the line of intersection between the rake face and the bisecting cross section of the vertex angle of the nose curvature is within ±10° relative to a <100> direction of the synthetic single-crystal diamond.
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