Coated cutting tool

A cutting tool comprising a substrate at least partially coated with a coating, said coating comprising a layer of Ti(C,N), a layer of Al2O3 and there between a bonding layer, wherein said Ti(C,N) layer having a thickness of 3-25 μm is composed of columnar grains, wherein an average grain size D422 of the Ti(C,N) layer is 25-50 nm, as measured with X-ray diffraction with CuKα radiation, the grain size D422 is calculated from the full width at half maximum (FWHM) of the (422) peak according to Scherrer's equation:

• D
• 4
• ⁢
• 2
• ⁢
• 2
• =
• K
• ⁢
• λ
• B
• 4
• ⁢
• 2
• ⁢
• 2
• ⁢
• cos
• ⁢
• θ
• wherein D422 is the average grain size of the Ti(C,N), K is the shape factor here set at 0.9, λ is the wave length for the CuKα radiation here set at 1.5405 Δ, B422 is the FWHM value for the reflection and θ is the Bragg angle, and wherein the Ti(C,N) layer includes a portion B1 that is adjacent to the bonding layer, and wherein an average grain size of the Ti(C,N) grains in portion B1 is larger than the average grain size D422 over the whole thickness of the Ti(C,N) layer, in the portion B1 of Ti(C,N) layer the Ti(C,N) grains has an average grain size of 130-300 nm as measured with Transmission Kikuchi Diffraction (TKD) on a plane view of the portion B1 of the Ti(C,N) layer extending in parallel with the substrate surface.