Continuous Cooling Transformation Behavior of Vercooling Austenite of Low Carbon-Manganese Steel

Continuous cooling transformation rules of Low Carbon-Manganese Steel were investigated on Gleeble-3500 thermomechanical simulator. The study indicates that as cooling rate increases, Ar3 loweres and Ar1 behaves similarly but much slowly. The microstructure composes of dominant ferrite and some pearlite. As cooling rate enhances, the ferritic grain become finer, when cooling rate is up to 30°C/s, a little bainite appears. With the increasing of cooling rate the dimension of ferrite decreases. Under the experimental deformation conditions, ferritic grain refinement gets weak when the cooling rate is greater than or equal to 20°C/s. Therefore, with a certain strain, ferritic grain can refined to some degree by accelerated cooling.