| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a cutting tool which is excellent in wear resistance, whose reduction in cutting performance caused by the wear of the tip of a cutting edge is suppressed, and whose cutting performance is kept for a larger number of cutting processes. <P>SOLUTION: Cutting edges 7, 8 are applied with a wear resistance coating 12 such as a diamond coating, the relief angle of the cutting edge is set to 15 degrees or larger, and during the cutting of a material to be cut, the edge of the coated tip of the cutting edge on a rake face 6 wears and as the wear progresses inwardly in the radial direction, the edge of the coated tip of the cutting edge on a relief face 10 is scraped by friction with the material to be cut and the base material thereunder is exposed, and furthermore, the exposed base material wears, and thereby, the relief face retreats inwardly in the radial direction and thus the cutting edge is honed and kept sharp. The cutting edge is formed so as to extend backward in the axial direction beyond a cutting edge maximum radius position RX where the diameter becomes the maximum for the first time when following the tip of the cutting edge backward in an axial direction AX from a tool tip O and the cutting edge maximum radius position retreats backward in the axial direction by friction. <P>COPYRIGHT: (C)2013,JPO&INPIT |
