Atomistic mechanism of grain boundary sliding with the example of a large-angle boundary Σ=5. Molecular dynamics calculation

The behavior of a large-angle boundary in a copper bicry stal under shear loading was studied by molecular dynamics simulation. The object to be studied was the boundary Σ = 5 (210)[001]. It is shown that grain boundary sliding can involve migration of the grain boundary perpendicular to the loading direction. The study covered both boundaries with a perfect symmetric structure and boundaries with a complex symmetric structure. Atomistic mechanisms of grain boundary sliding in the two cases were analyzed. It is found that the grain boundary structure affects the dynamics of the motion. Moreover it is revealed that the grain boundary velocity depends on the value of applied load. The disclosed behavior of grain boundaries under shear deformation can exert an appreciable effect on micro structural changes of material and hence on its properties and peculiarities under loading.