화학공학소재연구정보센터
Materials Science Forum, Vol.408-4, 1275-1280, 2002
Effects of sulfur segregation on selective grain growth and final texture in thin gauged grain-oriented 3% silicon steel
Correlation between sulfur segregation, surface-energy-induced selective growth and final texture has been investigated in 100mum thick grain- oriented 3% silicon steel. During final annealing under a vacuum or hydrogen atmosphere at 1200 degreesC, sulfur segregates to the free surface and grain boundaries, and a convex profile in concentration of surface-segregated sulfur versus final annealing time was observed. Such a convex profile is due to the loss of segregated sulfur by the evaporation or the H2S reaction, which forms a sulfur-depleted zone just below the strip surface. The surface-segregated sulfur induces a surface energy difference among crystal planes and causes a strong suppression of grain boundary movement. The annealing texture was changed from {110}<001> to {100} and subsequently to {111}, with increasing surface-segregated sulfur concentration. The surface-energy-induced selective growth of surviving Goss grains was observed within a segregated-sulftir free time range. After final annealing, the strip showed a strong Goss texture, resulting in a high magnetic induction (B-10) of about 1.9 Tesla.