Specific of the Recrystallization Driving Force Calculation on the early Stages of Thermomechanical Treatment of Aluminum Alloys

Abstract

The article investigates the effect of the strain rate on the driving force of recrystallization during hot working of the as-cast structure. For the study, we applied previously obtained experimental data of recrystallization kinetics during this stage of thermomechanical treatment. In addition, hot laboratory rolling, followed by saltpeter bath soaking, were performed in order to obtain supplemental data on grain structure size and orientations. Grain structure size was examined by optical microscopy, and its orientation was examined by X-ray texture analysis. The studies demonstrated, that overestimated recrystallization driving force not only results in erroneous kinetics estimation, but also gives excessive number of recrystallization centers and undersized grain structure. Besides, unaccounted effect of recrystallization driving force on grain size leads to distorted predictions of texture composition. In order to avoid this, it was recommended to apply an special exponential accumulated strain dependent coefficient.