COATED CUTTING TOOLS Russian patent published in 2018 - IPC B23B27/14 C23C16/40 C23C16/36 C23C16/44 

FIELD: metallurgy.

SUBSTANCE: invention relates to a coated cutting tool for machining metal with formation of chippingsand can be used for turning steels. Cutting tool has a wear-resistant coating obtained by chemical vapour deposition (CVD). Said coating comprises a layer of TiCN deposited by moderate temperature chemical vapour deposition (MTCVD), and a layer of α-Al₂O₃. Layer of α-Al₂O₃ has a texture coefficient TC (hkl) according to the Harris formula, , where I(hkl) - measured intensity (integrated area) of reflection (hkl), I₀(hkl) - standard intensity according to the PDF-card ICDD 00-010-0173, n is the number of reflections used in the calculation. Said texture coefficient TC (hkl) is determined using an X-ray diffractogram of the layer of α-Al₂O₃, measured using CuKα radiation and θ-2θ scanning, for reflections from the following crystallographic planes (hkl): (012), (104), (110), (113), (116), (300), (214) and (0 0 12), where TC (0 0 12) is more than 5. Total full width half maximum (FWHM) of the diffraction rocking curve peak of the (0 0 12) plane of α-Al₂O₃, measured on the back surface of the cutting tool using X-ray diffraction is less than 30°. TiCN layer has a ratio between the intensity over the integrated area of the diffraction rocking curve peak of the 220 plane and the intensity over the integrated area of the diffraction rocking curve peak of the 311, I₂₂₀/I₃₁₁ plane, which is less than 3 and determined by X-ray diffractogram of said TiCN layer measured using CuKα radiation.

EFFECT: cutting tool provides higher wear resistance, resistance to wear in the form of craters, higher resistance to plastic deformation of the cutting edge, as well as high performance in turning of steel.

7 cl, 3 tbl, 9 ex