Recrystallization control to obtain uniform fine grain size in hot rolling of HTP steel

In multi-pass rolling of microalloyed steel, the toughness properties are impaired by mixed grain size. In order to obtain a uniform fine grain size, it is essential to suppress partial recrystallization in the inter-pass times. In this regard, high niobium low interstitial high temperature processed (HTP) steel design offers distinct advantage in hot rolling. This is confirmed in the present work by physically-based modeling and experimental simulations. The application of the model for grain size control is demonstrated for two cases involving short (strip rolling), and long (Steckle mill rolling) interpass times respectively. The beneficial effect of high manganese design is also highlighted. (AU)