HARD COATING EXCELLENT IN WEAR RESISTANCE

摘要

PROBLEM TO BE SOLVED: To improve wear resistance and to enable application to a cutting tool and other parts by providing a specified compsn. consisting of Ti, Nb, Al, N and C. ;SOLUTION: The hard coating has a chemical compsn. represented by the formula; (Ti_xNb_yAl_z)(N_aC_1-a) (Where 0.6≤a≤1, 0.1≤z≤0.65, 0.05≤y≤0.75, 0x0.6, x+y+z=1 and each numerical value shows molar fraction). The crystal structure of the hard coating is a cubic rock-salt structure and the max. intensity ratio between diffraction rays on the (111) and (200) faces of the coating measured by X-ray diffraction preferably satisfies the relation of I (111)≥I(200). The coating is preferably formed by a cathode discharge type arc ion plating method. Since a target having the objective chemical compsn. is evaporated and ionized with arc of large electric current, the difference in evaporation rate between elements is small, the chemical compsn. of the coating is made almost uniform and the compsn. of the coating is easily controlled.;COPYRIGHT: (C)1999,JPO