TC4钛合金铜镀层的性能*

传统的氰化物镀铜工艺会对环境造成极大的危害,钛合金无氰镀铜技术具有较高的研究价值。采用无氰化物硫酸盐镀铜技术在TC4钛合金表面制备铜镀层,利用扫描电子显微镜和能谱仪对其镀层形貌、成分、结合力、磨损形貌进行分析,并利用电化学方法和摩擦磨损试验研究其抗蚀性与耐磨性。结果表明:无氰化物镀铜技术在TC4钛合金表面电镀铜可获得表面均匀致密,结合力良好的镀层;TC4钛合金表面电镀铜后,摩擦因数由0.520降至0.381,可见钛合金表面铜镀层通过减摩作用能有效的改善和提高其耐摩擦磨损性能。TC4钛合金镀铜和未镀铜表面均存在钝化区,两者维钝电流密度分别为1×10-2 A/cm2和4×10-5 A/cm2,均有较好的抗腐蚀性能,TC4钛合金镀铜后的表面抗腐蚀性能较基体有所降低。

Properties of Coating on TC4 Titanium Alloy by Copper Electroplating

As traditional cyanide copper plating process brings a serious damage to the environment, noncyanide pretreatment for TC4 titanium alloy has a great research value. Adopting noncyanide pretreatment and sulfate plating solution, Cu coating was prepared on TC4 titanium alloy. The micro morphology, composition, bonding force and wear morphology of the coating were analyzed by scanning electron microscope and energy dispersive spectrometer. Electrochemical methods and ballondisc wear test were used to test the corrosion and wear resistance of the coating. The results showed that the Cu coating prepared with no cyanide pretreatment has outstanding surface morphology, thickness and binding force. After the Cu coating is prepared on TC4 titanium alloy, the friction coefficient is reduced from 0.520 to 0.381. The Cu coating can improve the wear resistance of the TC4 titanium alloy by reducing the friction coefficient and the mass defect. Through electrochemical methods, the passivity phenomenon both appears on the Cu coating and the TC4 titanium alloy. The passivity current density of the Cu coating and TC4 titanium alloy are 1×102A/cm2 and 4×105A/cm2, respectively. Both of them have good corrosion resistance. However, the TC4 titanium alloy has a better one.