US 11,938,547 B2
Turning tool
Akihiko Ueda, Itami (JP); Takuya Nohara, Itami (JP); and Yutaka Kobayashi, Itami (JP)
Assigned to SUMITOMO ELECTRIC HARDMETAL CORP., Itami (JP)
Appl. No. 16/768,142
Filed by SUMITOMO ELECTRIC HARDMETAL CORP., Itami (JP)
PCT Filed Aug. 2, 2019, PCT No. PCT/JP2019/030411
§ 371(c)(1), (2) Date May 29, 2020,
PCT Pub. No. WO2020/031871, PCT Pub. Date Feb. 13, 2020.
Claims priority of application No. 2018-147806 (JP), filed on Aug. 6, 2018.
Prior Publication US 2020/0316691 A1, Oct. 8, 2020
Int. Cl. B23B 27/20 (2006.01); B23B 27/14 (2006.01); C01B 32/25 (2017.01); C23C 16/27 (2006.01); C30B 29/04 (2006.01)
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
OG exemplary drawing
 
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.