解理云母表面粘着特性的实验

为了解粘着行为的机理,对法向力测量系统进行了改进,利用应变测量和动态应变仪连续采集信号实现对分离力的实时动态测量,理论分辨率达到0.023mN。利用该系统对新鲜解理云母作为接触副的趋近分离实验现象进行了测量,发现新鲜解理云母直接接触时的分离力随着接触次数的增加而减小。在中间层存在水膜时,分离力增加约3倍,这验证了弯月面力对粘着力有显著影响,同时证明系统的动力学特性能够导致突跳现象的发生,且不一定伴随表面的破坏或塑性变形。

Adhesion characteristics of mica cleavage surfaces

The surface mechanics of adhesion were studied experimentally by measuring the normal forces on the surface. The system continuously records dynamic strain indicator signals so that the system can record real-time, dynamic measurements. The theoretical resolution is 0.023 mN. The system was used to measure the forces in an approach-separate experiment with newly cleaved mica. The tests show that the pull-off force of the newly cleaved mica decreases as the contact time increases. A thin layer of water between the mica surfaces increased the pull-off force three fold comparing with the dry contact. The results show that the meniscus force strongly influences the adhesive force and that the dynamic characteristics of the whole system can induce the "jump out" phenomenon that does not occur with surface damage or plastic deformation.