Dynamic compressive behavior of an ultra-lightweight magnesium foam

The dynamic response of an open-celled AZ91 magnesium foam with an ultra-low density of 0.05 g/cm3 was tested in compression at strain rates of about 1×103 s-1. The plateau stress of the magnesium foam exhibited a remarkable strain rate sensitivity, in a manner similar to that observed in the aluminum foam, ALPORAS. Also, the absorption energy for AZ91 foam at the dynamic strain rate of 1.4×103 s-1 was twice higher than that obtained at the quasi-static strain rate (1×10-3 s-1). The results suggest that it is important to know the actual strain rate sensitivity for a specific application to properly select foam materials.