Abstract
Motion of a superlattice screw dislocation (b = a〈111〉) at absolute zero under stress in the CsCl-type lattice has been computer simulated using simple hypothetical interaction potentials between atomic rows parallel to the Burgers vector. For the case of high antiphase boundary (APB) energies (γ110 ≳ 0.006μb; μ, shear modulus), the superlattice dislocation glides on the {110} plane, whereas for low APB energies (γ110 ≲ 0.006μb) it glides on the {112} plane, mostly on the twinning {112} plane. The Peierls stress is a minimum at χ = - 30° (the twinning {112} shear) and increases with increasing χ for both the above two cases. General trends of the experimental Ψ-χ and τy - χ relations at low temperatures reported for AgMg, FeAl and β-CuZn agree well with those obtained for the case of low APB energy.