The surface canning which shows the tenacity where the aluminum oxide formation which forms the hard enveloping layer is superior cemented carbide make cutting tool

摘要

PROBLEM TO BE SOLVED: To provide a surface coated cemented carbide cutting tool having a hard coated layer of good tenacity. ;SOLUTION: In a surface coated cemented carbide cutting tool having, on the surface of a cemented carbide base body, (a) a Ti compound layer made of one, two or more selected from a TiC layer, a TiN layer, a TiCN layer, a TiCO layer, a TiNO layer and a TiCNO layer, each having an average layer thickness of 0.1 to 5 μm (b) a I-TiCN layer having an average layer thickness of 3 to 15 μm, and (c) a high- orientation Al2O3 layer having an average layer thickness of 2 to 20 μm and a highest peak indicating a middle point half value of 0.10 to 0.25 degrees in a diffraction chart based on thin-film X-ray diffraction, these hard coated layers (a) to (c) being formed to have an entire average layer thickness of 6 to 35 μm by chemical or physical vapor deposition, the upper side of the high-orientation Al2O3 layer is made of low-orientation Al2O3 low in relative crystal orientation, and indicating a middle point half value or 0.35 to 0.60 degrees for a highest peak in the diffraction chart based on the thin-film X-ray diffraction, and the layer thickness of the low-orientation Al2O3 of the upper side is set equal to 10 to 40% of the entire layer thickness of the Al2O3 layer.;COPYRIGHT: (C)2000,JPO