Moving finite element simulation of dynamic interfacial crack propagation under shear-dominated loading

摘要

In this study, using the moving finite element method, numerical simulations of dynamc interfacial cracks subject to static remote shear load are carried out for a series of crack velocities from 0.4C_s~(1) to 2.0 C_s~(1), including subsonic, transonic and supersonic crack propagation. Two types of material-rigidity mismatches (3.0 and PMMA/Steel=64.2) are considered. Also, numerical simulations are carried out for tension-dominated models using the same set of crack velocities and material mismatches. For the tension-dominated models, it is found that the velocity factors of energy release rates do not depend on the material mismatch and always become zero in transonic and supersonic velocity regimes. For shear-dominated models, it is found that the energy release rate to the interfacial crack tip remains finite in transonic velocity regime, even when no contact occurs behind the propagating crack tip. Furthermore, from the distribution of the strain energy density, it is found that there is a large amount of strain energies stored in a wide area ahead of the crack tip. These suggest the possibility of existence of the transonic interfacial crack propagation.