Dynamic compression behavior of cenosphere aluminum alloy syntactic foam

The compression behavior of aluminum cenosphere syntactic foam has been studied and full stress–strain diagrams have been obtained for strain rates ranging from quasi-static to 1400/s. The foam exhibits peak stress at a strain of about 5%, especially during quasi-static compression, and the maximum value of stress around this strain is used to examine strain rate sensitivity and to determine an appropriate sensitivity parameter. The compressive strength and energy absorption of these foams attain a maximum at strain rates of approximately 750/s and then they decrease with further increase in the strain rate. The foam with coarser cenosphere appears to be more sensitive to strain rate. An empirical relation is developed for predicting the dynamic compressive strength of aluminum cenosphere syntactic foams. Explanation of the observed mechanical behavior in terms of the material failure mechanisms is provided.

► Aluminum-alloy syntactic foam with two cenospheres sizes is studied.
► Compression tests using SHPB are carried out for strain rates from 0.001 to 1400/s.
► Empirical equation is developed for dynamic strength of foam with cenosphere size.
► A critical strain rate is identified to provide the maximum strength limit.
► Transition of deformation mechanism is related to the critical strain rate.