For low carbon steels, thermomechanical processing in the intercritical (austenite–ferrite) temperature region has potential for generating an ultrafine grained structure. By using compressive deformation, the influence of temperature, strain rate and strain on the transformation kinetics were considered for developing a room temperature microstructure of fine ferrite grains. The flow behavior was also examined to determine the critical conditions for dynamic transformation and/or strain induced transformation using the stress–strain and strain hardening rate curves. Characterization of the microstructure after deformation in the intercritical region confirmed the occurrence of grain refinement with the presence of homogeneous and ultrafine ferrite grains.
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