Core structure and mobility of edge dislocations in face-centered-cubic chemically complex NiCoFe and NiCoFeCu equiatomic solid-solution alloys

Abstract

The elastic properties, core structures, critical resolved shear stresses (CRSSs), and mobility of 1/2〈110〉 edge dislocations in NiCoFe and NiCoFeCu equiatomic solid-solution alloys was predicted using molecular statics and dynamics simulations using two different embedded atom method (EAM) potentials. In particular, the Johnshon–Zhou potential is in good agreement with experimental measurements and observations. The calculated average intrinsic stacking fault energies for both alloys were 17 and 28 mJ/m2, and the mean stacking fault width in the absence of external stresses were 70 and 51 Å, respectively. The CRSSs for both alloys were between 50–60, 40–50, and 30–40 MPa at 10, 150, and 300 K, respectively. These results are in reasonable agreement with available experimental measurements and theoretical predictions. The atomistic simulations presented here can be used to predict and develop face-centered cubic chemically complex alloys with superior strength for various applications.