A novel method to define the effective average grain size of the materials with lath-typed microstructure: An example of medium manganese steel. (September 2021)

• Record Type: Journal Article
• Authors: Zhang, Yu; Ding, Hua; Zhu, Haokun; Zhang, Yutong
• Is Part Of: Vacuum. Volume 191(2021)
• Publication Date: 2021-09
• Subjects: Yield strength -- Hall-petch relationship -- Effective average grain size -- Medium Mn steel -- Ultrafine grained microstructure; Vacuum -- Periodicals; 621.55
• DOI: 10.1016/j.vacuum.2021.110313
• Languages: English
• ISSNs: 0042-207X

Abstract

Abstract: Based on the mechanism of dislocation pile-up, a novel and concise method is proposed to define the effective average grain size of the medium Mn steel with the lath-typed microstructure. In order to investigate the Hall-Petch relationship of the medium Mn steel with different microstructural morphologies, the granular and lath-typed microstructures are fabricated by intercritical annealing (IA) and austenite reversed transformation (ART), respectively. The yield strength of the ART sample (lath-typed microstructure) exhibits excellent consistency with the Hall-Petch relationship obtained from the IA sample (granular microstructure) when adopting the effective average grain size, indicating the feasibility of the proposed method. In addition, the effect of grain size on the mechanical properties is also investigated. Highlights: A novel method is proposed to define the grain size of lath-typed microstructure. The proposed method shows feasibility in evaluating the yield strength. The role of grain size on the mechanical properties is discussed.