Patent attributes
The present invention relates to a cutting tool, e.g. carbide insert, solid carbide drill or mill or carbide tip, particularly for milling of steels, stainless steel, HRSA, titanium or any alloyed material from any of these groups, comprising a cemented carbide substrate and an aperiodic multilayer coating with:a substrate of cemented carbide having a composition of from about 8 to about 11 wt-% Co, from about 0.1 to about 0.5 wt-% Cr and balance essentially tungsten carbideand a coating which is essentially an aperiodic multilayer consisting of layers A+B+A+B+A . . . where the sublayers A and B consist of AlxTi1-xN and TiyAl1-yN respectively. The typical average thickness of each A+B sequence is in the range from about 30 to about 300 nm and the total thickness of the coating in the range from about 0.5 to about 20 μm. The total chemical composition averaged over the whole coating consists of TizAl1-zN where z lies in the range from about 0.40 to about 0.70.