Phase Transformation Behavior during Continuous Cooling of Fe-C-Mn-Si Multiphase Steels

摘要

In the present paper, controlled cooling of Fe-C-Mn-Si multiphase steel was conducted by a laboratory hot rolling mill. The results show that polygonal ferrite, granular bainite and the stable retained austenite can be obtained through hot deformation and subsequent two steps cooling pattern. The amount of ferrite increased with the duration of intermediate air cooling during controlled cooling. The formation of the bainitic ferrite resulted in the carbon concentration enrichment in austenite further during the simulated coiling. This increases the stability of the remaining austenite. Satisfactory mechanical properties can be obtained through hot rolling process and two steps cooling pattern in this work due to the TRIP effect of the stable retained austenite.