Simulation, microstructure and austenite reconstruction of a medium carbon micro-alloyed steel subjected to an austenitising bending process

The austenitising bending process was conducted on a medium-carbon micro-alloyed steel by Gleeble 3500 thermomechanical simulator to comparatively investigate the microstructural and mechanical evolution through thickness of the bent plate. A combination of bainite ferrite, lath martensite and acicular ferrite with a presence of partial dynamic recrystallisation was the main microstructural features. The increased work hardening in the compressive and tension zones after austenitising bending operation can be ascribed to synergistic effects of dislocation pile-up/cells, and finer prior austenite grains. Also, the reliability of this study was verified from the consistency between the results of simulation and experiment, which would provide a valuable reference for the practical manufacturing technology of railway spring clips.