Studying the effect of strain rate on tensile properties of nanocrystalline Cu50Ni50 alloy using molecular dynamics simulation method

Abstract

In this paper, the effect of different strain rates on the tensile properties of nanocrystalline Cu₅₀Ni₅₀ alloy was investigated using the molecular dynamics simulation method, one of the simulation methods widely used in the field of nanomaterials today. The Voronoi method was applied to establish the nanocrystalline structure, and ATOMSK
software was used to create the tensile test specimens of the polycrystalline Cu₅₀Ni₅₀ alloy. The stress-strain relationship, phase transformations, lattice dislocations, shear strain and von Mises stress distributions were evaluated. The results showed that the higher the strain rate, the higher the tensile strength value of the nanocrystalline Cu₅₀Ni₅₀ alloy. The phase transition from the Face-Centered Cubic (FCC) structure to the Hexagonal Close Packed (HCP) structure is predominant, and the Shockley dislocation prevails during the tensile process. The atoms with high shear strain are mainly concentrated at the locations where the material is most severely deformed, while the atoms with high von Mises stress are mainly focused inside the grain boundaries.