The excellent combination of mechanical properties of dual phase (DP) steels arises from the distribution of hard martensite islands in the soft ferrite matrix. Hot rolling is a potential route for commercial production of flat DP steel products. The present work systematically studied the rolling schedule and run out table cooling strategy for production of DP steels. All the processing parameters: rolling temperature and strain, interpass time, temperature control on the run-out-table and the quenching time before coiling were simulated by deformation dilatometer and transferred to a 4-stand pilot rolling mill. The recrystallization behaviour during rolling was additionally investigated by a hot compression simulator and the recrystallized austenite grain size was determined by available equations. Due to the proper austenite conditioning, the martensite island size in the hot rolled sheet is rather small. This contributes to satisfactory mechanical properties as obtained from tensile testing. The γ-α transformation kinetics were investigated by phase-field modelling.
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