Orientation dependence of secondary recrystallisation in silicon-iron

Experiments and analyses have been carried out to reach a better understanding of the mechanism of Goss texture formation during the secondary recrystallisation of silicon steel processed by the single cold reduction route. A new experimental approach demonstrated the effect of misorientation on the growth rates of secondary grains and it is shown that these rates are controlled by the proportion of matrix grains having Sigma9 CSL relationships to growing secondary grains. It is considered that the Sigma9 boundaries have lower energy than general grain boundaries and so are less strongly inhibited by Zener drag. The relative infrequency of Sigma9 boundaries around the periphery of secondary grains is seen as evidence for their sacrificial behaviour. Other experiments involving growth of randomly oriented nuclei provide independent support for the important role of Sigma9 boundaries during secondary recrystallisation in this steel. (C) 2003 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.