Peierls barriers of a-type edge and screw dislocations moving on basal and prismatic planes in magnesium

Abstract

Exact shape of Peierls barriers are calculated for <a> edge and screw dislocation gliding on basal and prismatic planes in magnesium by using of several popular interatomic potentials. Comparison of these potentials is performed in order to describe their abilities and limitations. Stability of different types of dislocation cores are analyzed as well as their mutual transformations during dislocation slip. It was found that the Peierls stresses and barrier height are dependent on core type. It was concluded that transformations of dislocation cores along minimal energy paths have to be taken into account for development of analytical models of the slip in magnesium. The results are compared with available first-principles calculations.

Variability of Twin Boundary Structure in Computer Simulations of Tensile Twins in Magnesium

“…Consequently, predictions of simulations can be slightly different for different interatomic potentials. Recently, plasticity of magnesium were studied by using of embedded-atom method (EAM) potentials by different authors [10][11][12]. It was confirmed that, for instance, Sun at al.…”

Computer simulations of hydrostatic pressure influence on screw <a> dislocation slip in Mg

“…Варто зазначити, що, наприклад, популярний Liu та співавт. потенціал EAM [26] передбачає для гвинтової <a> дислокації лише компактне ядро на відміну від прогнозів ab-initio [24,27,28]. Деякі вдосконалені версії Kim та співавт.…”