ND//〈111〉 recrystallization in interstitial free steel: The defining role of growth inhibition

Abstract

Hot band, fully recrystallized, interstitial free (IF) steel samples were cold rolled to 10-80% thickness reductions. After characterizing the developments in deformed microstructures, 50-80% deformed samples were fully recrystallized at 650°C. Though different annealing times were used, use of a relatively lower annealing temperature and repeated trials ascertained absence of significant post-recrystallization grain coarsening. Recrystallization brought in a steady improvement in γ -fibre (ND//〈111〉) and drop in θ - fibre (ND//〈100〉). The only exception was 80% prior deformed microstructure, where the trend was reversed: enforcing a drop in texture estimated normal anisotropy or r¯ value. The study brought out growth inhibition of recrystallized γ -fibre grains, caused by non-γ fibre bands and by orientation pinning of recrystallized γ -γ boundaries, as the mechanism behind the observed trend reversal. © 2012 ISIJ.