A New Model for Interpass Softening Based on the Strain Hardening Rate Prior to Unloading

It is shown that the kinetics of softening between mill passes can be modeled more simply when the normalized strain (reduction) per pass is employed rather than the conventional strain. This method requires a second important input, namely the strain hardening rate at the end of preloading. Using this approach, the number of input parameters and experiments required for their determination are drastically reduced. The use of the Law of Mixtures to describe the behaviors of the recrystallized and unrecrystallized volume fractions is then illustrated. Finally, the approach required for quantifying the precipitation kinetics (in microalloyed steels) is described.