Effect of processing and microstructure on mechanical properties of complex-phase steels A review

Abstract

The main objective of this review is to provide a concise and comprehensive overview of the current understanding of the fundamental mechanisms governing the processing and mechanical performance of low-carbon advanced high-strength steels (AHSS) characterized by multiphase microstructures, with particular emphasis on complex-phase (CP) steels. A sound understanding of the synergistic interaction between recrystallization, precipitation, and phase transformation phenomena forms the basis for producing fine and homogeneous microstructure with tailored mechanical properties. This paper constitutes the first part of a two-part review and focuses on the relationships between processing routes, microstructural evolution, and mechanical properties. The principal hot-rolling and continuous annealing routes used to produce dual-phase (DP), transformation-induced plasticity (TRIP) and complex-phase (CP) steels are reviewed, emphasizing the roles of recrystallization, intercritical annealing, cooling strategy, bainitic transformation, precipitation strengthening, and microstructural refinement in controlling strength, ductility, and hole expansion behavior. The influence of Nb microalloying, phase transformations, and microstructural characterization techniques on the development of modern CP steels is also discussed. The second part of this review will address physical simulation and computational modeling, computer-aided process control, real-time online modeling, and the increasing integration of cyber-physical systems and artificial intelligence into steel processing and materials design, as well as challenges related to mechanical behavior simulation and future research trends.