Transformation Behavior of Austenite Continuous Cooling of Nb-Ti Micro-Alloyed Low Carbon Steel

The transformation behavior of Nb-Ti micro-alloyed low carbon steel during continuous cooling was studied trough thermomechanical simulator and metallographic analysis. The results show that the dynamic CCT diagrams shift to the left and upper compared with the static ones, the begin temperature of gamma ->alpha transformation is gradually lower with the increase of cooling rate. The high temperature deformation improves Ferrite and Pearlite transformation, also improves Bainite transformation and decreases ferrite transformation zone. The rapid cooling can obtain better obdurability mixed microstructure of Martensite and Bainite within a certain cooling rate after deformation.