Compressive behaviour of open-cell Al–Si alloy foam produced by infiltration casting

Open-cell Al–Si alloy foams with different densities were manufactured by vacuum infiltration. The foam with smaller NaCl as space holders showed a mixed scaffold structure consisting of abundant struts and cell walls. It was also found that the open-cell Al–Si alloy foam showed various defects containing micropores, microcracks and missing cell walls. The compression results indicated that the open-cell Al–Si alloy foams exhibited smoother stress–strain behaviour and higher compressive strength than that of previous studies, despite a larger number of defects in brittle Al–Si matrix. The successive occurrences of multiple deformation bands owing to the mixed structure and various defects were responsible for the smooth compression stress–strain behaviour.