Work

Enhancing mechanical properties of medium Mn steel by warm rolling based on laminated elemental segregation

Year: 2024

Type: article

Abstract: The hot-rolled microstructure of medium Mn steel has coarse grains and severe elemental segregation, resulting in low strength and plasticity. Constructing a multiphase structure, refining the microstructure, and regulating elemental segregation enhance the mechanical properties. In this study, liquid nitrogen treatment created a layered distribution of austenite and martensite. Warm rolling was then used to reduce layer thickness and refine grain structure. After liquid nitrogen and warm rolling treatments, the strength and plasticity of medium Mn steel increased to 1270 MPa and 23.3%, respectively, far exceeding the hot-rolled state (724 MPa, 12.8%). Warm rolling also triggers austenite reverted transformation (ART) and introduces high-density dislocations, further improving austenite stability. This strengthening effect is higher than that from intercritical annealing alone. Improved austenite stability delays the transformation induced plasticity (TRIP) effect, preventing brittle fracture and enhancing deformation coordination between layers, significantly increasing the plastic deformation capacity of medium Mn steel.

Source: Journal of Materials Research and Technology

DOI: 10.1016/j.jmrt.2024.08.060

Authors: Haifeng Chen, Baoxi Liu, Pingguang Xu, Wei Fang, Haochuan Tong, Fuxing Yin

Institutions: Hebei University of Technology, Japan Atomic Energy Agency, Guangdong Academy of Sciences

Language: English

Topic: Microstructure and Mechanical Properties of Steels

Subfield: Mechanical Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $1,430

Funders: National Natural Science Foundation of China, Natural Science Foundation of Hebei Province, Guangdong Academy of Sciences, Science and Technology Planning Project of Guangdong Province