盐雾腐蚀条件下Ti合金表面功能薄膜的摩擦磨损性能

目的研究Ti6Al4V合金、铬掺杂类金刚石(Cr-DLC)薄膜、钨掺杂类金刚石(W-DLC)薄膜和氮化钛(TiN)薄膜,在干摩擦和盐雾腐蚀气氛摩擦条件下的摩擦磨损性能。方法在商用Ti6Al4V合金表面通过非平衡磁控溅射制备Cr-DLC薄膜和W-DLC薄膜,通过多弧离子镀技术制备TiN薄膜。利用扫描电镜、显微硬度计、摩擦磨损试验机、白光干涉扫描轮廓仪,对薄膜的形貌、硬度、干摩擦和腐蚀摩擦性能、磨痕形貌进行测试分析。结果干摩擦条件下,Ti6Al4V合金表面沉积Cr-DLC、W-DLC和TiN三种薄膜的摩擦系数均比Ti6Al4V合金低;Ti6Al4V合金及其表面制备的三种薄膜在盐雾腐蚀气氛条件下的摩擦系数都比干摩擦条件下有所增加。与Ti6Al4V合金相比,Cr-DLC、W-DLC和TiN三种薄膜在干摩擦和盐雾腐蚀气氛摩擦条件下均减小了磨损体积。干摩擦条件下,W-DLC薄膜的磨损体积为0.0017 mm~3,耐磨性最好;盐雾腐蚀气氛摩擦条件下,TiN薄膜的磨损体积为0.0028 mm~3,表现出最佳的耐腐蚀磨损性能。通过磨痕形貌可以得出,盐雾腐蚀气氛摩擦条件下,Ti6Al4V合金表面制备的金属掺杂类金刚石薄膜的磨损受到磨粒磨损和腐蚀磨损双重机制的影响。结论三种表面功能薄膜在盐雾腐蚀气氛摩擦条件下都较好地保护了Ti合金,极大地减少了磨损损失。

Friction and Wear Properties of Functional Films on Ti Alloy Surface under Salt Spray Corrosion Conditions

The work aims to study friction and wear properties of Ti6Al4V alloy, chromium doped diamond-like carbon (Cr-DLC) films, tungsten doped diamond-like carbon (W-DLC) films and titanium nitride (TiN) films under the conditions of dry friction and salt spray corrosion friction. Cr-DLC films and W-DLC films were prepared on commercial Ti6Al4V alloy in the method of unbalanced magnetron sputtering. TiN films were prepared by adopting multi-arc ion plating technique. Morphology, hardness, dry friction performance, corrosion friction resistance and wear scar morphology of the films were tested and analyzed by using scanning electron microscope, microhardness tester, friction and wear tester as well as white light interference scanning profiler. Friction coefficient of Cr-DLC, W-DLC and TiN films deposited on the surface of Ti6Al4V alloy were lower than that of Ti6Al4V itself under dry friction condition. Compared with the condition under dry friction, the friction coefficient of Ti6Al4V and the three films prepared on its surface were increased in the salt spray corrosion atmosphere. Compared with wear volume of Ti6Al4V alloy, that of Cr-DLC, W-DLC and TiN films was reduced under the conditions of dry friction and salt spray corrosion. Under the dry friction condition, the wear volume of W-DLC film was 0.0017 mm3, and the film showed the best wear resistance. Under the salt spray corrosion condition, the wear volume of TiN film was 0.0028 mm3, and the film exhibited the best corrosive wear resistance. It could be concluded from wear scar morphology that the wear of metal-doped diamond-like carbon films prepared on the surface of Ti6Al4V alloy was affected by dual mechanism of abrasive wear and corrosion wear under the condition of salt spray corrosion. Ti alloy is well protected by the three kinds of surface functional films under the condition of salt spray corrosion friction, and wear loss is greatly reduced.