Effect of volume changes on hot rolling deformation behavior of non-oriented electrical steel

Abstract

In order to quantify the effect of volume changes due to temperature drop and phase transformation on hot rolling deformation behavior of non-oriented electrical steel and make up for the deficiency of traditional austenitic rolling model, mathematical models derived from experiments are established, and programmed to subroutines to be incorporated into the coupled temperature-displacement strip model. The calculated results of temperature field, phase field and stress field are then transferred into the rolls-strip coupling model to participate in rolling process. The results indicate that the temperature deviation along strip width direction can lead to an obvious transverse transformation difference. When only the volume change due to temperature drop is considered, the strip shows completely elastic "tensile stress in the edge, compressive stress in the middle", and the central thickness and quadratic crown of strip are increased slightly. When the volume changes due to temperature drop and phase transformation are both considered, the unexpected "secondary plastic deformation" is produced and the reverse distribution form of internal stress is presented, which significantly decrease the thickness and quadratic crown of strip. However, due to the average effect of tensile stress and compressive stress, both volume changes contribute little to the total roll force.