Numerical and Experimental Study of Quasi-Static Loading of Aluminum Closed-Cell Foams Using Weaire–Phelan and Kelvin Tessellations

Abstract

Study of porous materials, in particular closed-cell foams, has always attracted researchers’ interest due to the advantages these materials offer in applications where low weight, buoyancy, insulation, or energy absorption is of importance. In this study, quasi-static compressive experimental tests are conducted for low-, medium-, and high-density aluminum foams and their mechanical properties are obtained. In addition, two types of lattice structures based on regular repeating unit cells (Kelvin and Weaire–Phelan) are modelled and their suitability for predicting the mechanical behavior of closed-cell foams in quasi-static configuration is evaluated and compared. Due to the irregular structure of cast foams, it is computationally very expensive to reproduce numerical models with similar structural topology. Using tessellation method can be a step forward in investigating various parameters affecting the properties of closed-cell foams. The results indicated that as compared to Kelvin models, the Weaire–Phelan models better mimic the deformation of manufactured specimens. On the contrary, as compared to the Weaire–Phelan models, the mechanical properties obtained from the Kelvin models are in general closer to the experimental results. The study results also showed that as the foam density increases, the densification strain decreases, while all other mechanical properties (elastic modulus, yield stress, plateau stress, and energy absorption capacity) increase.