Impact response of aluminum foam core sandwich structures

Sandwich panels, comprised of metallic foam core and face sheets, are widely used to withstand impact and blast loadings. Based on the actual application requirements, the performance can be optimized with the proper combination of face sheets design. In this paper the impact responses of aluminum foams with various tailored face sheets, whose behavior represents elastic, elastic-ideally plastic and elastic–plastic strain work hardening, were investigated experimentally. The experiment was carried out using hemispherical indenters on blocks of aluminum foam with and without the face sheet. Competing failure modes for the initiation of failure are discussed based on comparison of energy absorption capacity. Results show that increase in thickness of foam and the use of face sheet enhances the impact energy absorption capacity. The type of face sheet not only affects the energy absorption capacity but also the failure mode for the foam blocks. Aluminum foam blocks with stainless steel sheet are strong enough to withstand the pre-designated impact loading without penetration damage. At the same time, this study also provides a comparison of the impact performance, in terms of impact energy and failure mode, among blocks with different face sheets under the low velocity impact.