A study of the recrystallization of an IF steel by kinetics models

The primary recrystallization of a 70, 80 and 90% cold rolled interstitial-free (IF) steel was studied using optical micrographs (OM) and microhardness tests. Both the JMAK model and a new recrystallization model were used to analyze the recrystallization kinetics. The experimental data plotted according to the JMAK model could be represented by straight lines with JMAK exponents n falling in the range from 1.3 to 2.6. The experimental data also showed good agreement with the new model, which involves three microstructural parameters. It can be used to quantitatively study recrystallization kinetics. For this purpose, the mobility (M) of the boundaries is obtained using a non-linear curve fit method. Trend analysis shows that M increases with annealing temperature and rolling reduction. Furthermore, the dependence of the mobility on initial strain can be interpreted in terms of solute drag theory.