SURFACE COATED CERMET CUTTING TOOL WHOSE HARD COATING LAYER EXHIBITS HIGH CHIPPING RESISTANCE IN HIGH-SPEED HEAVY CUTTING OPERATION

摘要

PROBLEM TO BE SOLVED: To provide a surface coated cermet cutting tool whose hard coating layer exhibits excellent chipping resistance in high-speed heavy cutting operation.;SOLUTION: The hard coating layer of this coated cermet cutting tool is constructed by the following (a) a lower layer and (b) an upper layer. (a) The lower layer includes: an adhesive Ti compound layer, which is formed of one or two or more layers of TiC layer, TiN layer, TiCN layer, TiCO layer and TiCNO layer, which are all formed by chemical deposition and has the total average layer thickness ranging from 0.1 to 5 μm; and a modified Ti-base carbonic nitride layer satisfying the composition expression: (Ti₁-_XCr_X)C1-_YN_Y (wherein X:0.005 to 0.05, Y:0.45 to 0.55 by atomic ratio). (b) The upper layer is constructed by an α-type Al₂O₃ layer having the average layer thickness ranging from 1 to 15 μm. The modified Ti-base carbonic nitride layer in the lower layer in the above shows a specified inclination angle frequency distribution graph.;COPYRIGHT: (C)2007,JPO&INPIT