Investigation of Structure-Property Relations in Porous Metals Using Finite Element Simulation

Abstract

A porous material can be regarded as a mixture of pores and solid phases, with effective thermal and mechanical properties that significantly differ from those of its base material. Material effective properties depend greatly on the structure and porosity. The effective properties of materials with different pore structures can vary greatly even for materials that exhibit the same porosity. Therefore, understanding the structure-property relationships is beneficial for designing optimum porous structures. The effective (thermal or electrical) conductivity value lies between the upper and lower bounds, corresponding to the horizontal and vertical lamella structures, respectively. The values of these bounds depend upon the porosity. However, many studies have simply treated these effective properties as only a function of the porosity, even though properties can differ at the same porosity. Herein, finite element simulations were performed to estimate the effective thermal and mechanical properties of spherical and cylindrical pore structures with different arrangements. More specifically, FCC- and HCP-type arrangements were considered for spherical pores, while parallel and perpendicular arrangements were considered for cylindrical pores. The results obtained were compared to the theoretical bounds and it was observed that the effective mechanical and thermal properties followed the power-law, whereas the effective yield strength did not. In summary, the results presented herein highlight the importance of pore structure in determining effective properties. Key words: porous material, pore structure, effective property, finite element simulation