Continuous Cooling Transformation Behavior of Hot Deformation Austenite in ER70S-6 Steel

By measuring the CCT curves of ER70S-6 steel under different cooling speed in Gleeble-1500 thermal simulator,CCT diagram was obtained according to metallographic analysis and hardness measurement,and the microstructure of product of the continuous cooling transformation occurring in ER70S-6 were investigated.The results show that the microstructure of the steel consists of ferrite + pearlite,ferrite + pearlite + bainite,and ferrite + pearlite + bainite + martensite during a the range of cooling rates from 0.1 ℃/s to 20 ℃/s.