SURFACE COVERED CUTTING TOOL WITH HARD COVERED LAYER DISPLAYING EXCELLENT ABRASION RESISTANCE IN INTERMITTENT HIGH FEEDING CUTTING WORK

摘要

PROBLEM TO BE SOLVED: To provide a surface covered cutting tool with a hard covered layer displaying excellent abrasion resistance in intermittent high feeding cutting work. SOLUTION: This surface covered cutting tool is constituted by evaporating and forming a lower part layer made of a Ti compound layer having total average layer thickness of 3 to 20μm and an upper part layer made of an Al2O3layer having average layer thickness of 2 to 15μm and having anαtype crystal structure in a chemically evaporated state on a surface of a tool base body constituted of WC group cemented carbide or a TiCN group cermet. The Al2O3layer existing on the lower part layer side and existing in a 30 to 50% layer thickness region of the upper part layer is constituted of an Al2O3layer showing a constitutional atomic covalent lattice point distribution graph a distribution ratio occupying in the whole ofΣN+1 ofΣ3 of which is 60 to 80%. COPYRIGHT: (C)2008,JPO&INPIT