Effect of heat treatments on the crushing behaviour and energy absorbing performance of aluminium alloy foams

Aluminium alloy foams are widely used as an energy absorber to dissipate kinetic energy during impact or shock events. Their mechanical properties can be adapted using heat treatment methods. Compressive tests were conducted on the Al–Mg–Si and Al–Mg alloy foams in the three conditions, namely as-fabricated (F), age-hardened (A) and T6-strengthened (T6), to assess the effect of heat treatments on their crushing behaviours and energy absorbing performances. The strain rates ranged from 10−3 to 2000 s−1, and the results show that T6-strengthened treatment can raise the strengths and energy absorbing capacities of Al–Mg–Si foams in both quasi-static and dynamic cases, but have little effect on Al–Mg foams. It has also been found that their densification behaviours are insensitive to the heat treatments.