Mechanical properties and dislocation evolution of Cu–Fe interfaces from molecular dynamics simulation

Abstract

Molecular dynamics simulations have been conducted to find out the cohesion property, tensile strength, and dislocation evolution of several Cu–Fe interfaces. It is found that Cu1‾11‾/Fe(110)-KS and Cu(1‾11‾)/Fe(110)-NW interfaces are not only energetically favorable with lower interface energies, but also have higher strength than Cu–Fe interfaces with other interface orientations. Simulations also reveal that the formation of Cu–Fe interfaces has an important effect to increase the tensile strength of Cu under tensile loading along the directions parallel to the interface due to the block of the dislocation movement by the interface. On the contrary, the tensile strength of the Cu–Fe interfaces is smaller than that of Cu along the direction perpendicular to the interface as a result of the weak interface cohesion. The simulated results are in good agreement with experimental observations in the literature, and could provide a deep understanding of mechanical property and dislocation evolution of Cu–Fe interfaces.