摘要 |
A coated cutting tool having a long tool life because of its excellent wear resistance even under the working condition that the cutting part is subjected to high temperatures resulting from high-speed, high-efficiency machining. The coated cutting tool has a coating formed over the hard-alloy substrate. The coating comprises a first compound layer made of oxycarbonitride of a metal belonging to the IVa, Va, or VIa group in the periodic table. The first compound layer has: (a) atomic ratios of carbon (x), nitrogen (y), and oxygen (z) that satisfy x>y>z; x+y+z=1; 0.74>x>0.35; 0.45>y>0.20; and 0.30>z>0.06; (b) an average layer thickness of 0.5 to 20 mum that constitutes at least one-half the average total thickness of the coating; (c) a columnar structure; and (d) in the X-ray diffraction analysis, the highest peak intensity lying at one of the (220), (311), and (422) planes. |