Coupled effects of texture, hardening and non-proportionality of strain on ductility in ferritic steel

Examination of dislocation distributions for an initially random texture subjected to non-proportional straining shows that differences in structures develop which are more pronounced under uniaxial as opposed to biaxial straining. Non-proportionality in strain path is shown to have a significant effect on strains to localization, leading both to increases and decreases in ductility depending upon level of non-proportionality. The basis for this behavior is the path dependence of the development of dislocation distributions. There is the potential, therefore, for the selection of pre-forming texture and non-proportionality path in order to maximize forming limit strains.