Fracture of interlocking asperities during sliding contact plays a central role in determining friction and wear of brittle materials. The local force to break surface asperities and subsurface crack propagation directly affect the frictional force, wear rate and evolution of surface roughness. Here, we study the fracture failure of an isolated asperity under a lateral contacting force using a systematic set of experiments and numerical simulations. Combining the generalized elastic fracture mechanics and the Euler-Bernoulli beam theory, we also develop an analytical model to predict the critical force at the onset of asperity fracture as a function of the asperity's shape and material properties. The developed model can be used to develop physics-based friction and wear models for brittle solids.

滑动接触时互锁凹凸的断裂在确定脆性材料的摩擦和磨损方面起着核心作用。破坏表面凹凸和局部裂纹扩展的局部力直接影响摩擦力，磨损率和表面粗糙度的演变。在这里，我们使用一组系统的实验和数值模拟研究在横向接触力作用下一个孤立粗糙体的断裂破坏。结合广义弹性断裂力学和Euler-Bernoulli梁理论，我们还开发了一个分析模型来预测粗糙断裂开始时的临界力与粗糙形状和材料特性的关系。所开发的模型可用于为脆性固体开发基于物理的摩擦和磨损模型。