Abstract: In order to study the influence of pore size on the compression mechanical properties of aluminum foam, ABAQUS aluminum foam modeling plug-in based on Voronoi model is used to build three-dimensional solid foam aluminum models. According to the response surface model of porosity on cell number and average cell wall thickness, foam aluminum models with different pore sizes under porosity (90%, 80%, 70%) are built. Quasi-static compression simulation with ABAQUS finite element simulation software is used to compare and analyze the influence of pore size on the compressive mechanical properties of aluminum foam. The rigid-plastic hardening model (R-PH model) of aluminum foam under uniaxial compression considering the influence of pore size is modified. The results show that with the same porosity, aluminum foam with smaller pore size has greater stress values at each stage during compression, the energy absorption per unit volume increases but the maximum energy absorption efficiency and the energy absorption capacity decrease, the densification strain and the plateau stress increase. Pore size has a significant influence on the plateau stress of aluminum foam with low porosity. The modified R-PH model considering pore size can well predict the compression mechanical behavior of aluminum foam with different porosity and pore size.

Key words: closed cell aluminum foam, three-dimensional Voronoi model, quasi-static compression, pore size, constitutive model