Patent ID: 6869668

Claim:
A cutting tool comprising: a body comprising sintered cemented carbide, cermet or ceramic; and a hard and wear resistant coating on at least functional parts of the body, said coating comprising a structure of one or more refractory layers of which at least one layer comprises an alumina layer having a thickness of 0.5-25 μm, and consisting essentially of single phase α-alumina textured in the [300]-direction with a texture coefficient larger than 1.5, the texture coefficient being defined as: T ⁢ ⁢ C ⁡ ( h ⁢ ⁢ k ⁢ ⁢ l ) = I ⁡ ( h ⁢ ⁢ k ⁢ ⁢ l ) I 0 ⁡ ( h ⁢ ⁢ k ⁢ ⁢ l ) ⁢ { 1 n ⁢ ∑ I ⁡ ( h ⁢ ⁢ k ⁢ ⁢ l ) I 0 ⁡ ( h ⁢ ⁢ k ⁢ ⁢ l ) } - 1 where I(hkl)=measured intensity of the (hkl) reflection, Io(hkl)=standard intensity of the ASTM standard, powder pattern diffraction data, card number 43-1484, n=number of reflections used in the calculation (hkl) reflections used are: (012), (104), (110), (113), (024), (116) and (300).