| 摘要 |
PURPOSE: Provided is a coated cermet cutting tool with hard coating layer of excellent chipping resistance when intermittently cutting various steels or cast irons at high speed. CONSTITUTION: The coated cermet cutting tool comprising a hard coating layer consisted of (a) Ti compound layer and (b) aluminum oxide layer on the surface of a tool base body formed of tungsten carbide based hard metal or titanium carbo-nitride based cermet, wherein the Ti compound layer as a lower layer is formed of one or more of layers selected from titanium carbide layer, titanium nitride layer, titanium carbo-nitride layer, titanium oxide layer, titanium carbo-oxide layer and titanium oxide-carbon-nitrogen to a total average layer thickness of 0.5 to 20μm by chemical deposition, and the aluminum oxide layer as an upper layer is constructed in an alpha-type crystal structure in the state that the aluminum oxide layer is formed by chemical deposition, has an average layer thickness of 1 to 30μm and shows the maximum peak in an inclination angle section ranging from 0 to 10 degrees in a bar graph formed by irradiating electron rays onto individual grains having hexagonal crystal lattice existing in the measurement range on the surface of grinding face using a field emission type scanning electron microscope and measuring an inclination angle for a normal line on the surface of the grinding face of (0001) face that is a crystal face of the grain, thereby dividing measured inclination angle values within a range of 0 to 45 degrees shown by the individual grains per a pitch of 0.25 degree and collecting measured inclination angle values existing the respective sections per each of the section. |
