| 摘要 |
PROBLEM TO BE SOLVED: To provide an end mill made of surface-coated cemented carbide and excellent in wear resistance in high speed cutting. SOLUTION: A surface of a tungsten carbide group cemented carbide substrate is laminated alternately with a first thin layer and a second thin layer, each having an average layer thickness of 0.01 to 0.1μm. Further, a hard coating layer having an overall average thickness of 0.8 to 10μm is physically vapor-deposited. The first thin layer is constituted of either of a single-phase structure layer composed of a compound nitride layer having a specified composition ratio of Ti and Al, or a single-phase structure layer composed of a compound carbonitride layer having the specified composition ratio of Ti and Al, or both of the layers. The second thin layer is constituted of either of a compound nitride layer having the specified composition ratio of Ti and Al, or a mixed-phase structure layer having a structure where an aluminum oxide layer is dispersed and distributed on a base metal composed of a compound carbonitride layer having the specified composition ratio of Ti, and Al, at a rate of 5 to 40 area % in a structural observation by a scanning electron microscope, or both of the layers.
|
