Microstructual observations indicate that the recrystallization of cold rolled extralow carbon steel sheets occurs due to the abnormal growth of selected subgrains in recovered subgrain microstructures. Based on this recrystallization mechanism, a new model for predicting the recrystallization behavior of a material with idealized microstructure was proposed by Humphreys. The model cannot, however, predict the recrystallization behavior of cold rolled steel sheets in the practice because of the complexities of their microstructure.
In this study, a model for predicting the recrystallization behavior of cold rolled extralow carbon steels has been developed based on the model by Humphreys. The feature of the present model is that the pinning and solute drag effects on the recrystallization behavior can be evaluated quantitatively.
Using the model, the influence of Ti addition on the recrystallization in extralow carbon steel sheets was discussed. The result indicates that the retardation of the recrystallization due to the addition of Ti is attributed mainly to the retardation of the subgrain formation in the recovery process, and the effect of the pinning of precipitates and the dragging of solute Ti atoms on the progress of recystallization are relatively small.