Texture evolution in thermomechanically control processed multiphase medium carbon microalloyed steel: Forged, rolled and low cycle fatigued microstructures

A ferrite-bainite-martensite (F-B-M) microstructure was produced in a medium carbon microalloyed steel through two routes, namely, low temperature finish forging or rolling, followed by a two step cooling and annealing. The texture formed in control forged and rolled material after two step cooling followed by annealing (TSCA) was examined. Texture investigation was also carried out after low cycle fatigue testing at low and high total strain amplitudes. Transmission electron microscopy was employed to study the microstructural evolution. Fatigue tested F-B-M microstructure obtained through the rolling route was stable up to a total strain amplitude of 0.6%. This paper reports the evolution of texture and microstructure in two-step cooled F-B-M microstructure and their stability during fatigue loading. © (2012) Trans Tech Publications, Switzerland.