Microscopic study for the behavior of grain boundary using molecular dynamics

Abstract

In this study, MD simulations have been performed to observe the behavior of a grain boundary in an aFe plate under 2-dimensional loading. In MD simulation, the acceleration of every molecule can be achieved from the potential energy and the force interacting between each molecule, and the integration of the motion equation by using the Verlet method gives the displacement of each molecule. Initially, four ot-Fe rectangular plates which have different misorientation angles of grain boundary were modeled by using the Johnson potential and Morse potential. We compared the potential energy of the grain boundary system with that of the perfect structure model, which does not have a grain boundary inside. Also, we could obtain the width of the grain boundary by investigating the local potential energy distribution. The tensile loading for each grain boundary model at room temperature was applied and the behavior of the grain boundary was studied. From this study it was clarified that when the Johnson potential is used, the obvious fracture mechanism occurs along the grain boundary. With the Morse potential, the diffusion of the grain boundary appears instead of the grain boundary fracture.

Atomic force microscopy-based nano-lithography for nano-patterning: a molecular dynamic study

“…MD simulation has already been applied to a wide range of fields, including crystal growth, nano-indentation, tribology, fracture, laser interactions, etc., in order to simulate the atomic scale motion of the material [11][12][13][14]. Also the related studies by Ueda and Iwata [15], Shimada et al [16], Konig and Senrath [17], Komanduri [18], and Fang [19] are particularly noteworthy.…”