Low velocity impact denting of HSSA lightweight sandwich panel

Slow speed impact by a small mass can cause residual denting without perforation of a fibrous core sandwich panel that has thin facesheets. Denting depends on the kinetic energy, compliance and nose shape of the colliding body as well as the compliance and mass density of the sandwich panel. Collision experiments were carried out with fibrous core sandwich panels of different sizes struck by colliding spheres at small velocities. Analytical models based on either quasi-static or dynamic deformation of plates were developed to calculate the impact force during low speed impact on circular sandwich panels. Finite element analysis using ABAQUS was performed to calculate impact damage on sandwich panels. Results of the analytical and numerical models and the experimental measurements were compared. The dependence of damage on both structural parameters and impact variables was investigated.