Solute diffusion during high-temperature plastic deformation in alloys

Solute volume diffusion during high-temperature plastic deformation in a substitutional solid solution alloy is analyzed theoretically. Both deformation-induced supersaturated vacancy enhanced diffusion effect and dislocation pipe diffusion effect are considered in the model. The model is applied to the prediction of deformation-enhanced phosphorus diffusion in γ-Fe. Deformation-induced supersaturated vacancy enhanced diffusion and pipe diffusion can both enhance the overall phosphorus diffusion coefficient, but the former effect plays a predominant role. At a certain temperature, the deformation-enhanced phosphorus diffusion coefficient is mainly dependent on strain and strain rate, and at each strain rate there is a steady state value for the enhanced diffusion coefficient.

► Supersaturated vacancy-enhanced diffusion and pipe diffusion can both enhance the overall solute volume diffusion.
► Supersaturated vacancy-enhanced diffusion plays a leading role in enhancing the overall solute diffusion.
► The deformation enhanced diffusion is dependent on strain, strain rate and temperature.