INCREASING OF WEAR-RESISTANCE OF TI-6AL-4 V ALLOY BY NITROGEN IMPLANTATION

Nitrogen ion implantation is used to improve the wear resistance of Ti -6A1-4V alloy. Different implantation doses up to 1 . 10(18)N(+)/cm(2) and E = 170 KeV were used. The unimplanted and the implanted specimen s were tested in a wear model system with oscillation loading. The res ults show, that the wear performance was influenced by implantation do se and also by mean pressure. It was found, that surfaces, which are p roduced by a high implantation dose (1 . 10(18)N(+)/cm(2)), exhibited greater were resistance than untreated Ti-6A1-4V alloy. The best wear behaviour was achieved by a high implantation dose (1 . 10(18)N(+)/cm( 2)) and a low mean pressure (p = 0,22 MPa) at the wear test. The diffe rence between the wear rate of the untreated and of the implanted spec imen can obtain a factor about 10. The effective depth of the implanta tion action is greater than the penetration depth of the nitrogen ions .