Compressive Behaviors and Deformation Mechanisms of Open-Cell Al-Si Foam

Open-cell Al-Si foams with varying cell sizes and pore structures are fabricated using infiltration casting. Foams with uniform cell sizes ranging from 2.0 to 4.0 mm and 1.5 to 2.0 mm exhibit typical open-cell walls. In contrast, a foam with a mixed cell size distribution (1.5 to 4.0 mm) demonstrates improved connectivity but exhibits more structural defects. Quasistatic uniaxial compression tests are performed to evaluate the compressive behavior of the foams. The deformation process and energy absorption mechanisms of three foams are comprehensively analyzed from macroscopic sample scale to pore scale using X-ray computed tomography. The results indicate that foams with smaller cell sizes deform uniformly, with the highest compressive strength of approximate to 20 MPa, while those with larger cell sizes exhibit localized deformation. The foam with mixed cell sizes and a hybrid scaffold structure (3D skeletal network) displays broader deformation zones and localized deformation, rather than distinct deformation bands.