| 摘要 |
PROBLEM TO BE SOLVED: To provide a cutting tool insert formed of coated cemented carbide, for machining a bimetal at an intermediate cutting speed and under a wet condition, which is particularly of great value at the time of face milling of an engine block made of cast iron, and an alloy containing aluminum and/or magnesium. SOLUTION: The cutting tool insert is formed of a base material and a coating. The base material contains WC, Co of 9 to 11 wt%, and an ordinary grain micronizer of a suitable amount for obtaining a mean WC particle size of less than 1μm. The coating consists of a first innermost layer made of TiC<SB>X</SB>N<SB>Y</SB>O<SB>Z</SB>containing homoaxial particles with a size of less than 0.5μm, and having a total thickness ranging from 0.1 to 1.5μm, wherein the following relationships hold, x+y+z=1, y>x, and z<0.2; a TiC<SB>X</SB>N<SB>Y</SB>layer containing rod-like particles with a mean diameter of less than 5μm, and having a thickness ranging from 1 to 4μm, wherein the following relationships hold, x+y=1, x>0.3, and y>0.3; a smooth particulate layer made ofκAl<SB>2</SB>O<SB>3</SB>with a particle size ranging from 0.5 to 2μm, and having a thickness ranging from 1 to 2.5μm; and a TiN outer layer having a thickness of less than 1μm. COPYRIGHT: (C)2005,JPO&NCIPI |
