Patent ID: 8084148

Claim:
A cutting insert, comprising: a cemented carbide substrate; and a coating; wherein said substrate comprises: about 5 wt% to about 7 wt% Co; about 0.05 wt% to about 2.0 wt% metals selected from the group consisting of Ti, Nb, Ta, and combinations thereof; and balance WC; wherein said substrate has a coercivity (Hc) of about 14 kA/m to about 19 kA/m and an S-value of about 0.81 and about 0.96; and wherein said coating comprises: a homogeneous layer of (Ti x Al 1-x )N; wherein x is between about 0.25 and about 0.50; wherein said homogeneous layer of (Ti x Al 1-x )N has a crystal structure of NaCl type and a total thickness of between about 1.0 μm and 5.0 μm, as measured on the middle of a face, and the cutting insert is configured for milling cast iron.