A comprehensive diffusion kinetics theory was formulated which described tracer and chemical diffusion in antistructurally disordered B2 intermetallics exhibiting positive or negative deviations from stoichiometry. The theory was based upon unit processes consisting of 6-jump cycles that could be assisted by intrinsic and extrinsic antistructural atoms of either atomic species. The Ising alloy model was used to illustrate the formalism, but the formalism could be adapted to other models. Expressions were developed for the tracer diffusion coefficients, the phenomenological coefficients, the intrinsic diffusion coefficients, the interdiffusion coefficient and the various correlation factor components. Results for the tracer and collective correlation factors and the vacancy wind factor (in interdiffusion) were in excellent agreement with the results of Monte Carlo computer simulations based upon single vacancy jumps.

Diffusion in Substitutionally Disordered B2 Intermetallics. I.V.Belova, G.E.Murch: Journal of Physics - Condensed Matter, 2002, 14[41], 9563-77