Abstract: A diamond sintered body tool (20) having superior adhesion resistance, chipping resistance and high strength includes a tool base material (22) including a diamond sintered body, and a surface layer (21) formed on a surface of the tool base material (22). The surface layer (21) includes at least one of silicon, a silicon oxide, a silicon carbide, a silicon nitride and a solid solution thereof. The tool base material (22) has an inner portion (22b) including a first content of an iron group metal, and a surface portion (22a) surrounding the inner portion (22b ) and including a second content of the iron group metal lower than the first content.

Abstract: A tool manufactured by brazing a hard sintered body such as a diamond or cBN to a tool substrate through a bonding layer comprising at least one of Ti and Zr by 15-65 wt % and Cu. Two ridges of the tool substrate on both sides each has a first ridge adjacent to and aligned with a ridge of the hard sintered body and a second ridge provided nearer to an inscribed circle of the tool than is the ridge of the hard sintered body. Also, an upright side face and a bottom of each seating groove formed in the tool substrate intersect each other at an angle smaller than the intersecting angle between a back side and a bottom of each hard sintered body.