Properties of basal and first order prism plane dislocations with Burgers vector 1/3<11•0> in α-Zr were investigated by computer simulation. Results for a recent interatomic potential (MA07) were assessed and compared with an older one (AWB95). The elastic constants were calculated with the inner relaxations allowed for and the energy and vector of metastable stacking faults were determined and compared with published ab initio estimates. The core of the screw dislocation spreads principally in the prism plane in the MA07 model, in contrast to basal plane dissociation in the AWB95 model, and the prism-to-basal ratio of the Peierls stress for the screw was 0.28 with the MA07 model, compared with 3.31 with the AWB95 model. Simulation of the dynamics of dislocation motion under applied stress reveal how the drag coefficient varies with slip system and temperature. The results for the MA07 model were consistent with the known slip geometry of Zr, suggesting that it offers significant advantages for large-scale atomic simulation of dislocation behaviour.

Dislocation Core Structure and Dynamics in Two Atomic Models of α-Zirconium. H.A.Khater, D.J.Bacon: Acta Materialia, 2010, 58[8], 2978-87