Patent ID: 7674520
Filing Date: 2010-03-09
Classification: C23C,Y10T

Abstract:
1. A PVD coated cemented carbide insert having an upper face (rake face), an opposite face and at least one clearance face intersecting said upper and opposite faces to define cutting edges wherein the cemented carbide has a composition of from about 86 to about 90 weight % WC, from about 1 to about 2 weight % (Ta,Nb)C and from about 8 to about 13 weight % Co, and wherein the cemented carbide insert is coated with a hard layer system, having a total thickness of from about 3 to about 30 μm, comprising a first layer of (Ti,Al)N with a thickness of from about 1 to about 5 μm, an alumina layer, with a thickness of from about 1 to about 4 μm, a ((Ti,Al)N+alumina)*N multilayer, where N≧2, with a thickness of each ((Ti,Al)N+alumina) layer is less than about 0.5 μm, and