| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a surface-clad cutting tool whose hard coating layer exerts excellent chipping resistance and defect resistance in a high speed intermittent cutting work.SOLUTION: A surface-clad cutting tool has a hard coating layer comprising the following lower, intermediate and upper layers on the surface of a tool base body: (a) the lower layer being a Ti compound layer comprising one, or two or more layers of the carbide, nitride, carbonitride, carboxide and carbonitroxide of Ti and having a total average layer thickness of 3-20μm; (b) the intermediate layer being an aluminum oxide layer comprising anαtype crystal structure having an average layer thickness of 0.5-5μm and a titanium oxide layer formed below the aluminum oxide layer and having an average layer thickness of 0.1-1μm; and (c) the upper layer being an another aluminum oxide layer in which the tabularly grown aluminum oxide crystalline phase having an average layer thickness of 1-25μm and an amorphous aluminum oxide phase exist. The above problem is solved by defining the crystal orientation, the occupancy ratio of the tabularly grown aluminum oxide crystalline phase in the upper layer or the like.</p> |
