Finite element analysis of a modified progressive damage model for composite laminates under low-velocity impact

In this paper, a 3D finite element model is established in ABAQUS/Explicit based on a modified progressive damage model to study the dynamic mechanical response and damage development in cross-ply composite laminates subjected to low-velocity impact. The 3D Hashin criterion and the damage evolution model with the through-thickness normal stress component sigma(33) are applied to predict the infra-laminar damage initiation and evolution. The cohesive elements with the bilinear traction-separation relationship are inserted between layers to predict the inter-laminar delamination induced by impact loading. A user-material subroutine VUMAT involving the modified progressive damage del of intra-laminar and inter-laminar damage is coded and implemented in the finite element package ABAQUS/Explicit. The numerical results of three different impact energies (7.35, 11.03 and 14.70 J) are analyzed by the impact force-time, force-displacement and energy-time histories curves as well as different damage modes. The respectable relationship between numerical simulation and experimental result indicates that the proposed modified method is more suitable for low-velocity impact on composite laminates under different impact energies than the previous method without sigma(33). Moreover, the effects of S-mt and S-mc on global mechanical response and local damage predictions for laminates are discussed in detail. It can be concluded that both of the coefficients should be adopted between 0.93 and 0.96 when using this damage model to simulate composite laminates under low-velocity impact.