Mechanical properties and deformation behavior of equiatomic CoCrFeMnNi high-entropy alloy foam: A molecular dynamics study

In recent years, the aerospace and mechanical industries have employed metal foams for High Energy Capacity applications. However, the porous nature of such metallic foams results in a drop in tensile properties. High Entropy Alloys (HEAs) have been reported to overcome the strength-ductility trade-off as opposed to conventional metals and their alloys. Based on this, an equiatomic nano porous CoCrFeMnNi HEA is investigated using molecular dynamics simulation to elucidate the deformation behavior and mechanical performance at different atom distributions, percent porosity, and pore locations. The findings indicated that the mechanical properties are independent of atom distributions. However, with an increase in percent porosity, a decline in the ultimate tensile strength was observed. Up to 66% reduction in tensile strength was recorded. A similar trend was observed under temperature variations. By varying pore location, either within or on the structure, the pores within the foam structure led to a significant reduction in properties. The deformation mechanism of the HEA foam was established via analyses of the dislocation distributions, stacking faults, crack nucleation, and propagation. The findings offer new insights for material design to produce high-performance HEA foams and a comprehension of its failure mechanism under loading. [Display omitted] •Mechanical strength of high entropy alloy foam is independent of atom distributions.•Strength of high entropy alloy foam relates inversely to porosity and temperature.•Dislocation mechanism and distribution of high entropy alloy foams under tension.•Pore locations affect mechanical strength in metallic foams.•Closed pores are more detrimental to mechanical properties of high entropy alloys.