Predicting thermal and mechanical performance of stochastic and architected foams

Abstract

This study conducted pore-scale simulations to estimate the stagnant thermal conductivity and mechanical performance of stochastic metal foams and architected metal foams. The stagnant thermal conductivity of 5-, 10-, 20- and 40-ppi commercial aluminum foams were estimated to be 6.74, 6.49, 5.97, and 7.16 W/m/K, respectively. Thermal conductivity depended mainly on porosity and was not a strong function of pore size. The pore-scale models simulated thermal conductivities of 40-ppi Al foam along three orthogonal directions are 7.16, 7.92, and 7.56 W/m/K, respectively, indicating a strong isotropic nature. Compared with stochastic foams, the architected foam with a triply periodic minimal surface showed 103% higher thermal conductivity, 488% higher stiffness, and 265% more energy absorption capability. The findings reported here not only provide a fundamental understanding of the interplay between performance and architecture but also open a new avenue to create multifunctional foams.