表面润湿性对水润滑Al-Mg合金摩擦学特性的影响

摘要

Self-assembled monolayers (SAMs)on Al-Mg alloy surface were prepared by self-assembled tech-nique.Water contact angles on SAMs were measured by contact angle measurement.Tribological characteris-tics of Al-Mg alloy with different SAMs were evaluated by CETR universal micro-tribometer.The results indi-cate that the wettibility of Al-Mg alloy surface can significantly be changed by SAMs.The Al-Mg alloy surfaces with FDTS,FOTS,OTS SAMs appear hydrophobic,however,the Al-Mg alloy surfaces with MPS,APS SAMs posess hydrophilic characteristics.The water contact angles for 5 kinds of SAMs are in the order from large to small,FDTS,FOTS,OTS,MPS,APS.The stronger of hydrophobicity of SAMs,the smaller of friction coef-ficients of Al-Mg alloy.For the same SAMs,the friction coefficient of Al-Mg alloy was lowest in water-j et lu-brication condition,middle in water lubrication condition,and largest in dry friction condition.%通过自组装技术在 A l-Mg 合金表面制备自组装分子膜,采用接触角测量仪测定了自组装分子膜的水接触角,采用多功能摩擦磨损试验机对制备不同自组装分子膜的 A l-Mg 合金在3种润滑方式下进行摩擦磨损实验。结果表明,制备自组装分子膜可显著改变Al-Mg 合金的表面润湿性,制备 FDTS、FOTS、OTS自组装分子膜的表面呈疏水性,制备 MPS、APS自组装分子膜的表面则呈亲水性,5种自组装分子膜接触角由大到小的顺序为 FDTS>FOTS>OTS>MPS>APS。自组装分子膜的疏水性越强,Al-Mg 合金的摩擦系数越小。同种自组装分子膜在干摩擦条件下摩擦系数最大,浸水润滑条件下摩擦系数有所下降,喷水润滑条件下摩擦系数最小。