Thermal Mechanisms of Grain Refinement in Steels: A Review

• Published in: Metals and materials international Vol. 27; no. 7; pp. 2078 - 2094
• Main Authors: Nasiri, Zahra, Ghaemifar, Sajad, Naghizadeh, Meysam, Mirzadeh, Hamed
• Format: Journal Article
• Language: English
• Published: Seoul The Korean Institute of Metals and Materials 01-07-2021; Springer Nature B.V; 대한금속·재료학회
• Subjects: Annealing; Austenite; Austenitic stainless steels; Characterization and Evaluation of Materials; Chemistry and Materials Science; Cold rolling; Controlled rolling; Dual phase steels; Engineering Thermodynamics; Grain refinement; Heat and Mass Transfer; High strength low alloy steels; Low carbon steels; Machines; Magnetic Materials; Magnetism; Manufacturing; Martensite; Materials Science; Metallic Materials; Processes; Recrystallization; Reversion; Solid Mechanics; Thermal cycling; Thermomechanical treatment; 재료공학; Steels; Martensite process; Thermal cycling; Grain refinement; Recrystallization processes
• ISSN: 1598-9623; 2005-4149
• DOI: 10.1007/s12540-020-00700-1

Thermal mechanisms of microstructural refinement in steels were reviewed. These include thermal cycling, martensite process, and static recrystallization (SRX), in which the dominant stage of microstructural refinement is governed by an annealing treatment of a deformed or an undeformed material. Recent progress in grain refinement by thermal cycling for the body-centered cubic, face-centered cubic, and dual phase (DP) steels was introduced. The application of the cold rolling and subsequent annealing of a martensite starting structure (martensite process) for grain refinement of low-carbon and DP steels was reviewed. The formation and reversion of strain-induced martensite in metastable austenitic stainless steels and their effects on the microstructural evolutions were critically discussed. Moreover, the repetition of the martensite process and its limitations were explained. Important findings on the SRX of ferrite and austenite for grain refinement as well as the recrystallization kinetics were presented. Finally, the concepts of controlled rolling for grain refinement and the interaction of austenite recrystallization and strain-induced precipitation in microalloyed steels during thermomechanical processing were also reviewed. This short overview presents the opportunities that the conventional and innovative processing routes can offer for grain refinement of steels.
Graphic Abstract