Construction of ternary Ni-Al-Ta potential and its application in the effect of Ta on 110 edge dislocation slipping in gamma '(Ni3Al)
QN Fan and CY Wang and T Yu, COMPUTATIONAL MATERIALS SCIENCE, 118, 288-296 (2016).
Based on experiments and first-principles calculations, a ternary Ni-Al- Ta embedded-atom-method (EAM) potential is constructed. The dislocation movement and mechanical behavior of gamma'(Ni3Al,Ta) is investigated using the molecular dynamics method with the ternary potential. The planar fault energies of Ni3Al calculated with the potential increase with the addition of Ta. The simulation results reveal that the edge dislocation has a very jerky movement, and both complex Lomer-Cottrell locks and dislocation dipoles are formed in the slipping process. The dislocation dipole can react with an edge superpartial dislocation and form a complex Lomer-Cottrell lock to block its movement. The addition of Ta can decelerate the motion of edge dislocations and inhibit the production of dislocation dipoles. It can be concluded that Ta has the potential to retard the deformation in gamma'(Ni3Al). The present paper provides valuable insight into the effect of Ta on the superdislocation mobility of gamma'(Ni3Al). (C) 2016 Elsevier B.V. All rights reserved.
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