Analysis of Friction Mechanism with Visualization Method of Partial Micro-slip at the Contact Interface

为了理解形状复杂、弹性非线性的两体接触时的摩擦机理，提出了一种结合摩擦系统、VTR、相关法和计算机图形学的局部滑移可视化方法，即“可视化摩擦系统”。利用该方法进行了多项研究。结果表明：(1)可视化结果显示，橡胶接触面滑移面积随切向系数的增大而实时增大。(2)当可视化观测到的粘滞面积为零时，宏观滑移发生，说明局部滑移可视化提供了足够好的分辨率。(3)从可视化结果得到了接触面界面处的局部滑移分布，表明局部滑移随着切向系数的增大而增大。(4)通过分析接触界面处夹杂物对静摩擦系数的影响可知，静摩擦系数随夹杂物尺寸的增大而减小，而静摩擦系数的变化取决于接触界面处夹杂物的位置。(5)接触界面处微滑移区域的传播方向可分为从接触区周围到接触区中心和从接触区前缘到接触区后方两种类型。(6)阐明了正方形、三角形、矩形、圆形、凹形和球形等复杂形状物体接触时的静摩擦系数和微滑移面积的变化。

In order to understand the friction mechanism in the case of contact of two bodes which have complicated shape and non-linear elastic properties, a new visualization method of partial slip is proposed by combining a tribosystem, VTR, correlation method and computer graphics as a "Visual-Tribosystem".By using this method, several studies were carried out. The obtained results may be summarized as follows :(1) Results of visualization show increase of slip area at the contact surface of rubber with increase of tangential coefficient in the real time.(2) It is shown that macro-slip occurs when stick area observed by visualization becomes zero, which means that partial slip visualization provides good enough resolusion.(3) From the results of visualization, the distribution of partial slip at the interface of contacting surfaces was obtained, and it indicated that the partial slip increased as a result of increasing the tangential coefficient.(4) From the analysis of effect of inclusion at the contact interface on static friction coefficient, it is clear that static friction coefficient decrease with increasing of inclusion size, and static friction coefficient changes in depend on position of inclusion at the contact interface.(5) Propagation direction of micro slip area at the contact interface can be classified into two types such as from around to center of contact area and front edge to behind of contact area.(6) Static friction coefficient and change of micro slip area in the case of contact of two bodies which have complicated shape such as square, triangle, Rectangular, circle, concave and spherical are clarified.