脉冲电流密度对Ni-WC/Co纳米复合镀层摩擦磨损性能的影响

目前,通过脉冲电沉积制备Ni-WC/Co复合镀层的研究报道较少。为了探究Ni-WC/Co纳米复合镀层对材料表面摩擦性能的影响,采用脉冲电沉积制备Ni-WC/Co纳米复合镀层,研究脉冲峰值电流密度对复合镀层晶体结构、晶粒尺寸和硬度的影响;室温下,在MM-W1B立式万能摩擦磨损试验机上测试复合镀层的摩擦磨损性能,分析其磨损机理。结果表明:随着峰值电流密度的增加,复合镀层晶粒尺寸先减小后增大,硬度则是先增大后减小,复合镀层的摩擦系数和磨损量都是先降低后升高;当峰值电流密度为10 A/dm2时,复合镀层的平均晶粒尺寸最小,硬度最高,摩擦系数和磨损量最低,耐磨性能最佳,复合镀层表面主要呈现轻微的划痕,且磨痕较窄,无疲劳磨损。

Effect of Pulse Current Density on Friction and Wear Properties of Ni-WC/Co Nanocomposite Coating

In order to explore the effect of Ni-WC/Co nanocomposite coating on the surface friction properties,Ni-WC/Co nanocomposite coatings were prepared by pulsed electrodeposition.The effects of pulse peak current density on the crystal structure,grain size and hardness of composite coatings were studied.At room temperature,the MM-W1B vertical friction and wear tester was used to measure the friction and wear properties of the composite coating and the wear mechanism was analyzed as well.Results showed that with the increase of the peak current density,the grain size of the composite coating decreased first and then increased,whereas the hardness increased first and then decreased;and meantime,the friction coefficient and the wear loss of the composite coating decreased first and then increased.When the peak current density was 10 A/dm2,the composite coating had the smallest average grain size,the highest hardness,the lowest friction coefficient and wear loss,and the best wear resistance,and the surface of the composite coating was mainly scratched lightly with narrow friction trace and no fatigue wear occurred.