Investigation on mechanical properties of nanofoam aluminum single crystal: using the method of molecular dynamics simulation

Abstract

In this research, the mechanical behavior of aluminum nanofoam was studied by the method of molecular dynamics simulation. The effective parameters in mechanical properties such as porosity, pore size, temperature, and strain-rate were investigated. The results showed that Young’s modulus, yield strength, and ultimate tensile strength were increased by decreasing the porosity and pore size. To accurately calculate the Young’s modulus (Es), the yield strength (σYS) and the ultimate tensile strength, combining the stress–strain curves with the potential and kinetic energy-strain curves was suggested as a standard method. The investigations about the effects of temperature and strain-rate on the tensile behavior showed that increasing temperature cause decrease in Es, σYS, and σUTS of foams. Moreover, the σUTS increased significantly while the Es and the σYS of the samples exhibited minor change with an increase in strain-rate. Nanofoam failure also occurred by stress localization, nucleation, and growth of cracks on the surface of pores.