Microstructural Evolution and Cellular Automaton Modeling of Recrystallization Behavior in AerMet100 High‐Strength Steel during Continuous and Interrupted Hot Deformation Processes

This study systematically elucidates the microstructural evolution laws of AerMet100 steel under different thermal deformation conditions, employing multiscale characterization techniques, including optical microscopy, electron backscatter diffraction (EBSD), and transmission electron microscopy (TEM), to analyze microstructural features. Quantitative analysis focuses on lath martensite width, geometrically necessary dislocation density, kernel average misorientation, and grain orientation spread, revealing the correlations between these parameters and parent phase austenite, thereby providing new insights into the genetic mechanism of microstructure during deformation. Through orientation analysis of deformed microstructures, the nucleation mechanism of recrystallization is investigated; fine microstructural correlations between lath martensite and high‐temperature austenite are established using TEM. A physically based cellular automaton model is developed, which couples dislocation density evolution to simulate recrystallization behavior under multiple thermomechanical processing paths. Its predictive capability is validated by EBSD measurement data of the original austenite. By tracking the evolution of dislocation configurations within cells during discontinuous thermomechanical processes, this study achieves cross‐scale linkage of microstructural evolution across different thermomechanical stages, providing a theoretical framework and simulation tool for microstructural control of ultrahigh‐strength steels under local heating and complex deformation conditions.