EFFECT OF SILICON ADDITION ON RECRYSTALLIZATION AND PHASE TRANSFORMATION BEHAVIOR OF HIGH-STRENGTH HOT-ROLLED TRIP STEEL

Because Si is a noncarbide forming element,a multiphase microstructure consist- ing of ferrite,bainite,and retained austenite,at room temperature,can be formed by controlling the thermomechanical process strictly.The cooling schedules must be restricted by the formation of pearlite and cementite.In the present article,a new integrated mathematical model for prediction of microstructure evolution during con- trolled rolling and controlled cooling is developed for a typical kind of low carbon Si-Mn TRIP steel,which consists of temperature simulation,recrystallization,and transfor- mation models.The influence of Si contents has been thoroughly investigated.The calculated results indicate that Si retards recrystallization,restrains austenite grain growth as well as accelerates polygonal ferrite transformation.