Recovery of mechanical properties during annealing of deformed metals has been modelled based on a microstructural representation comprising two elements, (ⅰ) the cell/subgrain structure (size δ) and (ⅱ) the dislocation density (ρ_I) within the subgrains. These two microstructural elements are treated as independent variables which during annealing define the flow stress (σ(T,t) as follows: σ(T,t)=σ_I + (1 -X (T,t)){α_1 MGb (ρ _I (T,t))~(1/2) + α_2 MGb /δ (T,t)} Where X(T,t) is the volume fraction recrystallized. The recovery reaction has been modelled in terms of solute pinning of migrating dislocations and sub-boundaries. The annealing out of dislocations has been analysed as a thermally activated glide reaction. Subgrain growth is treated analogous to normal grain growth, I.e. As a reaction controlled by sub-boundary migration. Recrystallization kinetics is modelled in terms of simple Avrami kinetics.
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