Experimental and numerical investigation on repeated low velocity impact response of aluminum plate using continuum damage mechanics approach

In this study، repeated low velocity impacts on aluminum plate are investigated experimentally and numerically. In order to investigate the failure mechanism، Lemitre''s model of the continuum damage mechanics is used. Numerical simulation is carried out employing a Vumat subroutine in Abaqus FE package. Repeated impacts are performed on the plate with the same level of energy. Plastic deformation is observed on the plate in the first impact. During the subsequent impacts and prior to crack initiation، the effect of strain hardening on the aluminum plate is observed. After crack initiation، the stiffness of the structure decreases. As the impacts continue، stiffness further decreases and the damage area increases، finally perforation and penetration appear on the plate. Also، the present model is validated by the experimental results. Comparison of numerical with experimental results shows a good agreement for the force-time and force-displacement histories.