Effect of structure design on compressive properties and energy absorption behavior of ordered porous aluminum prepared by rapid casting

Abstract

In this study, ordered porous aluminum specimens with four different cubic structures, i.e. basic truss structure, high density truss structure, strengthened truss structure and graded truss structure, were fabricated by rapid casting combining the selective laser sintering and the infiltration casting. Pure aluminum and ZL111 alloy were selected as matrix materials of ordered porous aluminum. Compressive properties and energy absorption behavior were investigated by quasi-static compression tests. The results showed that high density truss structure and strengthened truss structure exhibited higher compressive properties, resulting from short struts and strengthened joints. The energy absorption behavior of these structures showed similar tendency to their compressive properties. Strengthened truss structure and graded truss structure were capable of exhibiting higher specific compressive properties. Structure design to transform the deformation mechanism was effective for improving compressive properties and energy absorption behavior. Moreover, the results demonstrated that deformation processes depended on the comprehensive effect of ordered porous structures and matrix materials, indicating that the stretching-dominated mechanism combined with high strength matrix was conducive to higher compressive strength. Based on structure design in this study, ordered porous aluminum prepared by rapid casting showed more superior compressive properties and energy absorption behavior than other existed preparation methods.