Numerical study of low velocity impact resistance of gradient foam sandwich structures

Abstract

The metal foam material has a significant advantage in energy absorption during impact resistance and has good application potential in specific projects. In this paper, the impact resistance of metal-foam sandwich structures with different multilayer density gradients is investigated by simulation numerical modelling under low-velocity heavy impact. The conclusion indicated that the negative gradient and hourglass-shaped gradient structures have more advantages over the positive gradient and shuttle-shaped gradient structures in terms of impact resistance and energy absorption when the impact energy is the same. Compared to the uniform density core structure, the maximum increase in core specific energy absorption and structure specific energy absorption of the gradient core structure was 33.94 % and 10.36 %, respectively. The present study can provide a theoretical basis to design gradient foam core structures with both lightweight and high performance, and to rationally optimise the density gradient for the sandwich structure.