Migration of low angle 〈110〉 tilt boundary in Fe-3wt%Si bicrystals

The kinetics of grain boundary migration for low angle 〈110〉 tilt boundary with misorientation angle of 6° was experimentally studied at various temperatures between 1200 and 1625 K using Fe-3 wt%Si solid solution bicrystals by capillarity technique. The migration velocity of the low angle tilt boundary was much smaller than that of the Σ9 coincidence boundary. The driving force and mobility of the moving grain boundary were calculated from the migration velocity, the curvature and the grain boundary energy. According to the calculation, the small migration velocity of the low angle tilt boundary is considered to be due to the small mobility and the small driving force (the grain boundary energy). But the migration mechanism of the low angle tilt boundary was as same as that of the Σ9 coincidence boundary. At the low temperatures, the migration was controlled by the diffusion of Si that interacted with the grain boundary. On the other hand, at the high temperatures, it was controlled by the grain boundary diffusion.