Patent ID: 7056602

Claim:
A cutting tool insert comprising a substrate and a coating wherein the coating comprises one or more layers of refractory compounds of which at least one layer comprises a precipitation hardened (Ti y Al x Me 1-x-y )N based layer, where Me is one of the elements Zr, Hf, V, Nb, Ta, Cr, Mo, W or Si, and wherein: x is between 0.55 and 0.80; a ratio, R=x/(x+y), is between 0.50 and 0.85; a sum of Ti and Al subscripts, S=x+y, is between 0.7 and less than 1.0; a ratio of the peak width, F 10/90 , FW10% M or FW90% M meaning Full Width at 10% and 90% of the maximum peak value reduced with the background, measured using X-ray diffraction with Cu Kα radiation of the 200 peak at approximately 43°2θ of the (Ti y Al x Me 1-x-y )N coating is higher than 7.5; a ratio between the area of the h-AlN (100) peak at approximately 33°2θ (=A(h-AlN) 100 ) and the c-(Ti y Al x Me 1-x-y )N (200) peak at approximately 43°2θ (=A(c-(Ti,Al,Me)N) 200 ) called K, wherein K=A(h-AIN) 100 /A(c-(Ti,Al,Me)N) 200 , and K is between 0 and 0.3; and the layer has a single (Ti y Al x Me 1-x-y )N (200) peak.