Mathematical Modeling of the Mean Flow Stress, Fractional Softening and Grain Size during the Hot Strip Rolling of C-Mn Steels

Abstract

The logs for plan C-Mn grades form four different hot strip mills were analyzed in order to calculate the mean flow stress developed at each stand. The calculation, based on Sim's equations, takes work roll flattening, redundant strain, and the forward slip ratio account. The stresses are compared with the predictions of a model based on an improved Misaka mean flow stress equation in which strain accumulation as well as the kinetics of static and dynamic recrystallization are fully accounted for. A good fit is observed between the model predictions and the mill data, with agreement generally falling within the interval ±15%.