Interpenetrating phase composite foam based on porous aluminum skeleton for high energy absorption

This paper presents a study on mechanical response of porous aluminum skeleton/rigid polyurethane foam interpenetrating phase composites (IPCs) at different strain rates. Mechanical properties and failure mechanisms of IPC were identified. Results shown that the strain rate sensitivity of IPC is mostly caused by foamed filler while the deformation mechanisms are still dominated by aluminum skeleton. The aluminum skeleton exhibited lower total energy absorption at high strain rates because of the decrease in dynamic compressibility. However, the two constituent phases simultaneously contributed their high toughness and outstanding dynamic response to the IPCs. Also, compared with IPCs composed of solid polymers, the foamed filler significantly improved the compressibility, mechanical properties and strain rate sensitivity of IPCs. The suggested constitutive model adequately captured dynamic response of IPCs by comparisons with experiments. All results show that the metallic/polymeric interpenetrating phase composite foam is of high potential in energy dissipation and impact protection.