SURFACE COATED CERMET CUTTING TOOL HAVING EXCELLENT HARD COATED LAYER EXERTING DISPLACING EXCELLENT CHIPPING RESISTANCE UNDER HIGH SPEED AND DEEP CUTTING CONDITION

摘要

PROBLEM TO BE SOLVED: To provide a surface coated cermet cutting tool having excellent hard coated layer exerting excellent chipping resistance under high speed and deep cutting conditions.;SOLUTION: The hard coated layer, 1 to 15μm thick on a total average layer thickness, of the surface coated cermet cutting tool comprising a hard coated layer made from a complex nitride layer made of Ti, Al and B physically vapour-deposited in the surface of a cermet base body has component concentration distribution structure wherein along the layer thickness direction, the Al and Ti contents continuously vary in the region where the Al highest content point and the Ti highest content point exist alternately and repeatedly at a specified interval and the two points are adjacent to each other. In addition, the Al highest point satisfies a composition formula [Al_1-(X+m+n) Ti_X Si_mB_n]N (where, X, m and n represent 0.20 to 0.45, 0.01 to 0.10, and 0.01 to 0.10 in an atomic ratio respectively), and the Ti highest content point satisfies a composition formula [Ti_1-(Y+m+n)Al_Y Si_mB_n] N (where, Y, m and n represent 0.05 to 0.20, 0.01 to 0.10, and 0.01 to 0.10 in an atomic ratio respectively), and the interval between the both points adjacent to each other must be 0.01 to 0.1μm.;COPYRIGHT: (C)2004,JPO