Continuous Cooling Transformation Microstructure and Mechanical Property of 1 000 MPa Low Carbon Bainitic Steel

The microstructure of Si-Mn low carbon bainitic steel during continuous cooling was investigated by Gleeble-2000 thermal simulation test.Furthermore,the low carbon bainitic steel was also manufactured in the Shougang Steel Rod Rolling Plant.The effects of the process factors on the microstructure and the mechanical properties were studied.The results show that the cooling rate has a direct impact on both the microstructures type and properties.Full bainitic microstructures with UTS is as high as 1 000 MPa could obtain for this series of low carbon bainitic steel at a cooling rate of 2.0 ℃/s.Fine bainitic structure with good plasticity and impact properties could be obtained through the controlled rolling process.