Patent ID: 7153562

Claim:
A coated cemented carbide cutting tool insert, said coating comprising: a first, innermost layer system of at least two layers of TiC x N y O z with x+y+z≦1; and a second multilayer system comprising from about 5 to about 31 alternating layers of Al 2 O 3 and TiC x N y O z (x+y+z≦1), the Al 2 O 3 -layers having an individual layer thickness of <0.5 μm and the TiC x N y O z -layers from about 0.01 to about 0.2 μm with a total thickness of the multilayer from about 1.0 to about 4.0 μm, and wherein the multilayer is exposed along the edge line and into the rake and flank face, such that the exposure on the rake face (a) is greater than about 0.03 and less than about 0.9 mm, the exposure on the flank face (b) is greater than about 0.02 and less than about 0.2 mm and a>b.