Effect of surface segregation of sulfur on recrystallization kinetics in 3% Si–Fe alloy strip

Abstract

Effects of bulk content of sulfur on sulfur segregation and surface energy induced recrystallization kinetics have been investigated in two alloys containing 6 and 30 ppm sulfur. During final annealing under a high vacuum, the convex profile in sulfur concentration, which is attributed to sulfur segregation and evaporation, corresponded to the trough in magnetic induction, irrespective of bulk sulfur content. During annealing, surface energy induced secondary and tertiary recrystallization were in turn observed. While the grain boundary pinning effect of segregated sulfur was very weak in the alloy containing 6 ppm sulfur, the grain boundaries in the other alloy were strongly pinned by the segregated sulfur. Under the relatively higher sulfur atmosphere appearing in the alloy containing 30 ppm sulfur, the growth rate of {100} grain was absolutely governed by the Zener term related to the segregation concentration of sulfur. Through such a recrystallization process, a complete {110}〈001〉 Goss texture was formed, and magnetic induction higher than 1.9 T was obtained in both alloys after final annealing for 14.4 ks.