| 摘要 |
Provided is an end mill that suitably maintains wear resistance in the outer peripheral section of a bottom edge and that makes it possible to enhance chip discharge properties in the vicinity of the center of rotation of the bottom edge. In the end mill, the outer periphery of the tip section of an end mill body that rotates around an axis has formed thereon a plurality of chip discharge grooves that extend from the tip of the end mill body toward the rear end thereof, an outer peripheral edge is formed on an outer peripheral-side ridge section of a wall surface of each chip discharge groove that faces the end mill rotation direction, a bottom edge that extends from the tip of the outer peripheral edges to the inner peripheral side of the end mill body is formed on the tip section of the end mill body, and a cutting edge section that comprises at least the outer peripheral edges and the bottom edge is covered by a hard coating layer. At a rake face of the bottom edge that includes the center of rotation of the end mill, the hard coating layer is removed toward the outer side of the radial direction of the end mill body across a range of 0.1-0.25D with respect to the outer diameter (D) of the end mill body. |
