The effects of hot deformation on the bainitic transformation of a low carbon steel during continuous cooling were comprehensively studied through in situ high-energy synchrotron X-ray diffraction, dilatometry, and ex situ microstructural characterizations. The obtained results indicated that the prior deformation of austenite at 950 °C accelerates the bainite formation at the early stages. During the ongoing of the transformation, both the overall kinetics of bainite and carbon enrichment of austenite are lower in deformed austenite. The bainitic microstructure developed from deformed austenite is more refined and presents the same retained austenite content at room temperature with slightly lower carbon content when compared with the undeformed sample. Besides, a significant higher dilatation strain was measured during the bainitic transformation in the deformed sample, which can be explained by the crystallographic texture in hot deformed austenite. The evolution of the peak broadening of the {220}γ and {211}α reflections during bainitic transformation are discussed in detail.

通过原位高能同步加速器X射线衍射，膨胀法和非原位分析，全面研究了热变形对低碳钢连续冷却过程中贝氏体相变的影响。微观结构表征。所得结果表明，奥氏体在950°C的先验形变加速了贝氏体的早期形成。在转变过程中，变形奥氏体中贝氏体的整体动力学和奥氏体的碳富集都较低。由变形奥氏体形成的贝氏体组织更加细化，与未变形样品相比，在室温下具有相同的残留奥氏体含量，碳含量略低。此外，在变形样品的贝氏体转变过程中测得明显较高的膨胀应变，这可以用热变形奥氏体中的晶体织构来解释。{220} γ和{211} α的峰展宽的演变 详细讨论了贝氏体转变过程中的反射。