Analysis of aluminium nitride precipitation proceeding concurrently with recrystallization in low-carbon steel

Abstract

Aluminium nitride precipitation proceeding concurrently with the recrystallization process in a low-carbon Al-killed steel is modelled. The model calibration and the analysis of the interaction between the precipitation and recrystallization were carried out on the basis of experimental data of Meyzaud and Parniere. Once model parameters have been determined using the data on precipitation in the purely deformed and purely recrystallized state, the model can be used to predict the AlN fraction precipitated under the condition of overlapping recrystallization. It turns out that recrystallization alters the kinetics of AlN precipitation. The precipitation rate is reduced significantly at an early stage of recrystallization and then increases at the stage of the recrystallization interruption. The analysis shows that the overall slowing down of the precipitation is due to its slowing down within the unrecrystallized regions. This effect is assumed to be associated with the redistribution of nitrogen atoms from the unrecrystallized regions to the recrystallizing interface.