Determination of Recrystallization Stop Temperature from Rolling Mill Logs and Comparison with Laboratory Simulation Results

Abstract

The tempreature of no-recrystallization, T_nr, was measured by means of laboratory torsion rests for three low carbon steels. The T_nr values for these steels were also established from rolling mill log data obtained from the Algoma plate mill; these were found to be virtually identical to those from torsion tests. The mill log calculations were carried out by organizing the Sims roll force equations into a spreadsheet software for desktop personal computers. The results of both the torsion testing and mill log calculations compare well with previously developed correlations between T_nr and the chemical composition, and between A_r3 and the composition. It was also found that the overall levels of the mean flow stresses calculated from the mill logs are close to those determined from torsion testing. This excellent agreement confirms that laboratory torsion testing can provide a convenient and very effective simulation of industrial hot rolling operations.