| 摘要 |
The present invention provides a cutting tool that achieves cutting with high precision. The cutting tool of the present invention includes a cutting edge composed of a polycrystalline body including high-pressure-phase hard grains that contain one or more elements selected from the group consisting of boron, carbon, and nitrogen, the polycrystalline body being formed by subjecting a non-diamond carbon material and/or boron nitride, serving as a starting material, to direct conversion sintering under ultra-high pressure and high temperature without adding a sintering aid or a catalyst, in which letting the radius of curvature of the nose of the cutting edge of the cutting tool be R1, the sintered grains constituting the polycrystalline body have an average grain size of 1.2×R1 or less and a maximum grain size of 2×R1 or less. |
