论文标题
静态摩擦系数取决于外部压力和由于前体滑动而导致的块形
Static Friction Coefficient Depends on the External Pressure and Block Shape due to Precursor Slip
论文作者
论文摘要
Amontons定律指出，固体物体上的最大静态摩擦力与载荷成正比，并且与明显的接触区域无关。该定律表明静态摩擦系数不取决于外部压力或物体形状。在这里，我们使用有限元方法（FEM）在刚性底物上数字研究3D粘弹性块的滑动运动。宏观静态摩擦系数随着对象的外部压力，长度或宽度的增加而降低，这与Amontons定律相矛盾。前体滑动发生在块滑动之前的块和基板之间的2D接口中。宏观静态摩擦系数的减小是在散装滑动前的临界区域的临界区域缩放。对简化模型的理论分析表明，散装滑动是由于速度渗透局部摩擦引起的准静态前体滑动的不稳定性而导致的。我们还表明，临界滑动区域决定了宏观静态摩擦系数，这解释了FEM模拟的结果。
Amontons' law states that the maximum static friction force on a solid object is proportional to the loading force and is independent of the apparent contact area. This law indicates that the static friction coefficient does not depend on the external pressure or object shape. Here, we numerically investigate the sliding motion of a 3D viscoelastic block on a rigid substrate using the finite element method (FEM). The macroscopic static friction coefficient decreases with an increase in the external pressure, length, or width of the object, which contradicts Amontons' law. Precursor slip occurs in the 2D interface between the block and substrate before bulk sliding. The decrease in the macroscopic static friction coefficient is scaled by the critical area of the precursor slip before bulk sliding. A theoretical analysis of the simplified models reveals that bulk sliding results from the instability of the quasi-static precursor slip caused by velocity-weakening local friction. We also show that the critical slip area determines the macroscopic static friction coefficient, which explains the results of the FEM simulation.
