A study on the microstructural changes in hot rolling of dual-phase steels

In this study, hot rolling behavior of a low alloy steel in the dual-phase region is studied. The effects of various process parameters such as initial temperature, soaking time, rolling speed and the cooling conditions are investigated. Then, mechanical testing and microstructural studies are performed and the effects of process parameters are studied and finally the optimum rolling program is determined based on the achieved results. The results show that rolling speed significantly alters the final microstructures and mechanical properties. Higher rolling speed results higher volume fraction of ferrite phase. In addition, the optimum dual-phase microstructure for this steel can be obtained with; an initial rolling temperature of 900 ◦C, after 30 min soaking time, a strain rate of 3.8 s−1 and cooled at the rate of 250 ◦C /s. C 2006 Springer Science + Business Media, Inc.