On the relationship between the twin internal structure and the work-hardening rate of TWIP steels

Fe–Mn–C and Fe–Mn–Si–Al TWIP steels deformed under the same conditions exhibit different work-hardening rates. The present study investigates the microstructure of plastically deformed Fe–Mn–C and Fe–Mn–Si–Al samples, particularly the internal structure of the mechanically generated twins and their topology at the grain scale. Twins in the Fe–Mn–C steel are finer and full of sessile dislocations, rendering this material distinctly stronger with an improved work-hardening rate.