Surface-coated high-speed tool steel cutting tools to demonstrate the chipping resistance of hard coating layer is excellent in high speed heavy cutting machining of difficult-to-cut materials

摘要

PROBLEM TO BE SOLVED: To provide a cutting tool made of surface coated high speed tool steel having a hard coating layer exhibiting excellent chipping resistance in high-speed heavy cutting of material hard to cut.;SOLUTION: In this cutting tool, the following hard coated layer is deposited on the surface of a high speed cutting tool steel substrate. The hard coated layer includes: an upper layer and a lower layer, (a) both of which are formed of (Cr, Al, V) N, wherein the upper layer has a layer thickness ranging from 0.5 to 1.5 μm, the lower layer has a layer thickness ranging from 2 to 6 μm, (b) the upper layer has an alternately laminating structure of a thin layer A and a thin layer B, both of which have an average layer thickness per layer of 5 to 20 nm, the thin layer A is formed of a (Cr, Al, V) N layer satisfying the formula: [Cr_1-(A+B)Al_AV_B]N, and the thin film B is formed of a (Cr, Al, V) N layer satisfying the formula: [Cr_1-(C+D)Al_CV_B]N, and (c) the lower layer has a single phase structure and is formed of (Cr, Al, V) N layer satisfying a formula: [Cr_1-(E+F)Al_EV_F]N.;COPYRIGHT: (C)2007,JPO&INPIT