Experimental and Analytical Study on Multiscale Cushioning and Energy Absorption of Aluminum Foam at Different Strain Rates

In this research, the compressive behavior of closed-cell aluminum foam was examined across a broad strain rate spectrum, spanning from 0.005 s⁻1 to 2000 s⁻1. Utilizing an enhanced Hopkinson bar apparatus, the deformation and fracture mechanisms of the foam were captured through high-speed videography. Additionally, a microscale finite element model was developed to elucidate the dynamic deformation characteristics of aluminum foam at multiple scales. The findings indicate that the material’s response is highly strain rate-dependent, with both stress levels and energy absorption efficiency escalating as the strain rate rises. Moreover, the damage progression in aluminum foam manifests as a progressive collapse pattern.