二氧化硅及其硅烷自组装膜微观摩擦力与粘着力的研究(Ⅰ) 摩擦力的实验与分析

STUDY ON MICRO FRICTION AND ADHESION FORCE OF OTS SELF-ASSEMBLED FILM(Ⅰ) EXPERIMENT AND ANALYSIS OF FRICTION

使用原子力 /摩擦力显微镜在 5 %— 99%的相对湿度范围 ,研究了二氧化硅和二氧化硅基体上十八烷基三甲氧基硅烷自组装膜 (简称OTESAM/SiO2 )表面摩擦力和粘着力随湿度的变化规律 .实验表明OTESAM/SiO2 不仅能明显改善二氧化硅基体表面的摩擦性能 ,而且在 2 0 0nN(接触区Hertz压力约为 0 .8GPa)的载荷条件下表现出良好的抗磨性能 .由于强的亲水性 ,二氧化硅表面的摩擦力随湿度的增大先逐渐增大 ,然后急剧减小 .相反 ,OTESAM /SiO2 由于其良好的斥水性 ,表面的摩擦力在高湿度条件下略有减小 ,它可望成为微型机械和高速磁记录系统中较为理想的边界润滑剂 .

The adhesion characteristic of surfaces of SiO 2 and the self\|assembled film of octadecyltrime\|thoxysilane (OTE SAM) on the surface of SiO 2 under the relative humidity of 5%—99% were studied using atomic force microscopy/friction force microscopy.Experimental results indicate that the adhesion force of SiO 2 increases first with the relative humidity and then decreases sharply.However,the adhesion force of OTE SAM surface hardly changes with the relative humidity due to its strong hydrophobe property.The mechanism of the adhesion force changing with the relative humidity has been analyzed from the viewpoint of surface tension,van der Walls force,and basic bond forces.