Comparison of torsion and plane-strain compression for predicting mean yield strength in single-and multiple-pass flat rolling using lead to model hot steel

The deformation and recrystallisation behaviour of commercially pure lead has been studied using torsion, plane-strain compression and laboratory rolling. It has been shown that for strains used typically in rolling (≤ 0.3) the three modes give very similar values of stress and work-hardening. Furthermore, the rate of static recrystallisation between intervals of deformation is very similar. Dynamic recrystallisation occurs at much larger strains in torsion than in plane-strain compression, which leads to increasing differences in mean yield strength with increasing strain. Constitutive equations of the stress-strain-strain rate and static recrystallisation behaviours are presented.