MODELING AND SIMULATION OF A PROPAGATING CRACK AT A BI-MATERIAL INTERFACE UNDER IMPACT LOADING USING LS DYNA

This paper presents simulation of a propagating crack at a bimaterial interface. The computation simulates dynamic crack propagation experiments conducted on a modified Hopkinson bar. Commercial purity Aluminum and automotive steel 440 WGA are used to constitute a layered bi-material interface. Two configurations are tested, the first with the initial crack in aluminum and the second with the initial crack in steel. The crack tip stress in steel is higher than the crack tip stress in aluminum due to a higher modulus of elasticity of steel. With the initial crack in steel, it is expected that the propagating crack will run out of energy and as it enters aluminum it will get arrested due to crack tip plasticity. In both configurations higher impact velocities led to higher crack initial energies.