Title: Dual Role for Heterogeneity in Dynamic Fracture Show Chinese title

Title: 动态断裂中异质性的双重作用

Abstract: Are heterogeneous materials harder to break than homogeneous ones? Predicting rapid crack propagation in the presence of inhomogeneities remains a challenge. Linear perturbations leave the net speed of fracture unchanged. We obtain a nonlinear equation of motion for planar crack fronts to gain insight into the dynamic fracture of moderately heterogeneous solids. The coupling of the front geometry to the heterogeneity landscape renormalizes the energy dissipation and the crack velocity. In materials whose toughness is weakly sensitive to crack speed, such as silica glass, heterogeneity results in increased dissipation and slower crack propagation. However, heterogeneity has a reduced effect and may even facilitate fracture in strongly velocity-dependent materials. Show Chinese abstract

Abstract: 异质材料比均质材料更难破裂吗？ 在存在不均匀性的条件下预测快速裂纹扩展仍然是一个挑战。 线性扰动不会改变断裂的净速度。 我们得到了平面裂纹前沿的非线性运动方程，以深入了解中等异质固体的动态断裂。 前缘几何形状与异质性景观的耦合会重新调整能量耗散和裂纹速度。 在韧性对裂纹速度敏感性较弱的材料中，如石英玻璃，异质性会导致能量耗散增加和裂纹扩展变慢。 然而，在强速度依赖性材料中，异质性的影响会减小，甚至可能促进断裂。