An analytical method for characterizing grain boundaries around growing Goss grains during secondary recrystallization

Shape and misorientation of each grain boundary that surrounds the growing Goss grain is analyzed using OIM (Orientation Image Microscopy) of partiall y secondary recrystallized silicon steel specimens. Shape is characterized by two novel parameters called Grain Chord Length (GCL) and Grain Bulge Hei ght (GBH) that are explained in derail in this paper. The results suggest t hat 20 degrees -45 degrees misoriented boundaries migrate faster than the l ow (< 20 degrees) and high (> 45 degrees) angle boundaries that surround th e growing Goss grains. The island grains observed inside the growing Goss g rains mainly have either low (< 20 degrees). high (> 45 degrees), or CSL (C oincident Site Lattice) misorientations. This also confirms the higher migr ation rate of 20 degrees -45 degrees misoriented boundaries during secondar y recrystallization. (C) 2001 Acta Materialia Inc. Published by Elsevier Sc ience Ltd. All rights reserved.