| 摘要 |
Disclosed herein is a hard sintered cutting tool, the tool life of which can be further increased. In this hard sintered body cutting tool, a rake face of an edge portion is formed by a major surface of a first sintered body layer containing at least 80 percent by volume and less than 98 percent by volume of diamond, while a flank of the edge portion is formed by a second sintered body layer containing at least 30 percent by volume and less than 75 percent by volume of cubic boron nitride (CBN). The first sintered body layer is formed to have a thickness of at least 0.02 mm and less than 0.1 mm, and to be in a thickness ratio of at least 1:5 to the second sintered body layer. Thus, chipping resistance of the rake face is improved by the first sintered body layer, while wear resistance of the flank is improved by the second sintered body layer. As the result, it is possible to suppress progress of local wear and chipping, whereby the life of the cutting tool is increased as compared with the prior art. |
