Steel components absorb impact energy by plastic deformation whilst composite materials absorbing it by damage mechanisms
such as ®ber debonding, ®ber fracture, and matrix cracking. Therefore, in order to properly substitute metal components with
composite ones in industrial applications, the impact property of composite materials must be well known. In this study, the impact
behavior of sheet molding compounds (SMC), which is widely used in automobile industry due to its relatively low cost and high
productivity, was examined both experimentally and numerically. In order to investigate the impact behavior of SMC, an experimental
study was carried out by setting up a drop weight impact test system. Using this system, the dissipated impact energies of
SMC ¯at plates were measured to investigate the in¯uence of the mass and shape of impactor, initial velocity, and specimen
thickness on the impact behavior.
For numerical predictions, a modi®ed damage model for SMC was developed and adopted in the user de®ned material subroutine
of the commercial simulation program LS-DYNA3D. For the sake of improving eciency of impact simulations, the SMC
material property was determined in consideration of the local dierences of the ®ber volume fractions. The dissipated impact
energies under various conditions and the reliability of the developed impact simulation process were examined through comparisons
of the predicted data with the experimental results.
From this comparison, it was found that, in the scope of current study, the specimen thickness is the most important parameter
that should be considered in the design of SMC components for the aspect of impact behavior.