HARD COATING FOR CUTTING TOOL

• Main Authors: AHN SEUNG-SU, GWON JIN-HAN, PARK JE-HUN
• Format: Patent
• Language: Chinese; English
• Published: 23.07.2021
• Subjects: CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; METALLURGY; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION

A hard coating for cutting tools according to the present invention is a hard coating for cutting tools which is formed adjacent to a hard matrix by a PVD method, and is characterized in that: the hard coating has a thickness of 0.5-10[mu]m in total and one or more nitride layers and one or more oxide layers wherein the one or more nitride layers are each 0.1-5.0[mu]m in thickness and composed of AlaTibMecN (Me is at least one selected from Si, W, Nb, Mo, Ta, Hf, Zr, and Y, 0.55<=a<=0.7, 0.2<b<=0.45, 0<=c<0.1) or AlaCrbMecN (Me is at least one selected from Si, W, Nb, Mo, Ta, Hf, Zr, and Y, 0.55<=a<=0.7, 0.2<b<=0.45, 0<=c<0.1) in a cubic phase, and the one or more oxide layers are each 0.1-3.0[mu]m in thickness and composed of gamma-Al2O3 in a cubic phase; when the number of compositionally discontinuous interfaces across the entirety of the hard coating including the hard matrix is n, 4<=n<=9; the ratio of the microhardness of the nitride layer (H1) to the microhardness (H2) of the oxide layer satisfies 1.03