Journal of the Mechanics and Physics of Solids ( IF 5.3 ) Pub Date : 2023-06-07 , DOI: 10.1016/j.jmps.2023.105345 M.R. Marulli, J. Bonari, J. Reinoso, M. Paggi
Indentation tests are largely exploited in experiments to characterize the mechanical and fracture properties of the materials from the resulting crack patterns. This work proposes an efficient theoretical and computational framework, whose implementation is detailed for 2D axisymmetric and for 3D geometries, to simulate indentation-induced cracking phenomena caused by non-conforming contacts with indenter profiles of an arbitrary shape. The formulation hinges on the coupling of the MPJR (eMbedded Profile for Joint Roughness) interface finite elements which embed the indenter profile to efficiently solve the contact problem between non-planar bodies, and the phase-field model for brittle fracture to simulate crack evolution and nonlocal damage in the substrate. The novel framework is applied to predict cone-crack formation in the case of indentation tests with smooth spherical indenters, with validation against experimental data. Then, the methodology is employed for the very first time in the literature to assess the effect of surface roughness superimposed on the shape of the smooth spherical indenter. In terms of physical insights, numerical predictions quantify the dependencies of the critical load for crack nucleation and the crack radius on the amplitude of roughness in comparison with the behavior of smooth indenters. Again, the consistency with available experimental trends is noticed.
中文翻译:
使用光滑或粗糙压头预测球形压痕测试中锥体裂纹的耦合方法
压痕测试在实验中主要用于根据产生的裂纹图案来表征材料的机械和断裂性能。这项工作提出了一种有效的理论和计算框架,其实现针对 2D轴对称和 3D 几何形状进行了详细说明,以模拟因与任意形状的压头轮廓不相容接触而引起的压痕诱发裂纹现象。该公式取决于 MPJR(eMbedded Profile for Joint Roughness)界面有限元(嵌入压头轮廓以有效解决非平面体之间的接触问题)和相场模型的耦合脆性断裂来模拟基材中的裂纹演化和非局部损伤。该新颖的框架用于预测在使用光滑球形压头进行压痕测试时锥体裂纹的形成,并根据实验数据进行验证。然后,该方法首次在文献中用于评估表面粗糙度叠加对光滑球形压头形状的影响。在物理见解方面,与光滑压头的行为相比,数值预测量化了裂纹成核的临界载荷和裂纹半径对粗糙度幅度的依赖性。再次注意到与现有实验趋势的一致性。