HIGH-TEMPERATURE CARBURIZATION PROPERTY OF MEDICALGRADE FORGED CoCrMo ALLOY IN CH₄GAS

Medical grade forged CoCrMo alloys were carburized by the high- temperature gas carburizing process . The effect of high- temperature carburizing behavior on mechanical properties was investigated. The phase compositionand surface micro- hardness as well as wettability of carburized layer were respectively studied by X- ray diffraction （XRD），micro-hardness test and optical dynamic/static contact angle meter. Friction and wear characteristics were investigated on a ball- on- disc testing machine under Tyrode’s solutions. The experimental analyses indicated that hard Cr₃C₂ phase was formed on the carburized layer. Surface properties including micro-hardness and wetting properties as well as wear resistance of carburized medical grade forged CoCrMo alloys were improved compared to untreated sample.