基于自组装技术改性处理钛金属的摩擦学特性研究

为了使钛金属应用于具有相对运动的摩擦副,采用自组装技术对钛金属表面进行改性处理,并对制备的试样进行紫外照射.利用接触角测量仪、原子力显微镜和微摩擦磨损试验机对制备的试样进行表征和摩擦学特性测试,探讨不同方法进行钛金属表面羟基化的作用效果,并分析载荷、滑动速度以及紫外照射对试样摩擦学特性的影响.结果表明:Piranha溶液结合紫外照射能有效地提高钛基底的羟基化程度,经FOTS(Perfluorooctyltrichlorosilane)自组装分子膜改性处理的钛金属表面平整均匀,具有疏水特性和良好的摩擦学性能.Si_3N_4球与FOTS自组装分子改性处理试样间的摩擦系数随载荷和滑动速度的增大而增大.紫外照射5 min可有效地提高FOTS自组装分子膜改性处理的效果,在降低摩擦系数的同时,薄膜也具有良好的耐久性.

Tribological Properties of Modified Titanium Based on Self-Assembled Technique

In order to use titanium in frictional pair with relative motion, titanium surfaces were modified by self-assembled method and the prepared samples were irradiated by ultraviolet radiation/ozone photochemical process. The characterization and tribological properties of samples were conducted by contact angle measuring meter, atomic force microscopy and microtribometer, and the hydroxylation of titanium surfaces by different methods was explored. The effects of load, sliding velocity and ultraviolet radiation on the tribological properties of samples were analyzed. The results show that the combining Piranha solution with ultraviolet radiation/ozone photochemical process can prove the effect of titanium surfaces hydroxylation. The titanium surface modified by FOTS SAMs is uniform and exhibits good hydrophobic and tribological properties. The friction coefficient between Si3N4 balls and sample surfaces modified by FOTS SAMs increases with load and sliding velocity increasing. The effect of modification treated by FOTS SAMs can be improved by an ultraviolet radiation/ozone photochemical process for 5 min. The durability of friction pairs is retained in the case of reduction of coefficient of friction for the modified titanium surfaces