Axial crushing of metal foam-filled square columns: Foam density distribution and impactor inclination effects

In this paper, the effects of foam density distribution and initial impactor inclination angle on crushing behaviour of metal foam-filled thin-walled square columns have been investigated. The simplified version of an existing pressure dependent self-similar constitutive model with tensile failure for metal foam has been implemented in ABAQUS/Explicit code. Random distribution of cubic regions with normal distribution of density has been created. The analyses have been accomplished for three distinct foam densities, two extreme random distributions (fine and coarse), and five different impactor inclination angles. A local effect on folding patterns of columns filled with low-density foam has been identified. Furthermore, unstable bending mode of collapse appears in the case of slightly inclined impactor and medium and high-density foams. In addition, for high-density foam-filled specimens global buckling can initiate by just letting the density of foam vary inside the sample.