Comparison of quasi-static and dynamic compression behavior of closed-cell aluminum foam

Abstract

Aluminum foams have the potential to be used as structural material for impact energy absorption applications due to their extended constant stress region during compression. The compressive behavior of closed-cell aluminum foams synthesized by liquid melt route using TiH2 as a blowing agent is studied in the present work. Both quasi-static (ε˙=1×10−3 s−1) and dynamic (ε˙∼750 s−1) compression tests were carried out on foam specimens having relative density ranging from 0.062 to 0.373 and average pore diameter in the range of 2.2mm to 4.5mm. The dynamic tests were conducted using a split Hopkinson pressure bar (SHPB) apparatus with a hollow aluminum transmitter bar. The results of the study indicated that the plateau stress of aluminum foam increases with relative density and strain rate. Additionally, at high strain rates, an increase in the energy absorption capacity was observed. Such higher energy absorption capability during dynamic compression is beneficial when the material is used for impact energy absorption applications.