Work

Accelerating bainitic transformation and enhancing mechanical properties by chemical heterogeneity in ultrafine bainitic steel

Year: 2025

Type: article

Abstract: This study employed a processing route (CPBT) integrating a cold-rolled pearlite precursor with rapid heating to regulate bainitic transformation and mechanical properties of ultrafine bainitic steel. The results indicated that the bainitic transformation was significantly accelerated by the CPBT treatment, promoted by both an increased density of nucleation sites from cold-rolling-induced grain refinement and preferential nucleation in Mn-/Cr-depleted austenite regions. The enhanced transformation kinetics also resulted in a pronounced refinement of blocky retained austenite. Furthermore, the CPBT process introduced chemically heterogeneous bainite, characterized by refined bainitic ferrite laths and thickened Mn-/Cr-enriched film-like retained austenite, in contrast to the elemental homogeneity of conventional bainite. This microstructure improved tensile strength through grain refinement strengthening, while the sustained transformation-induced plasticity effect from the chemically heterogeneous retained austenite during deformation enhanced elongation.

Source: Materials Today Communications

DOI: 10.1016/j.mtcomm.2025.114397

Authors: Hui Guo, Shaoguang Yang, Jianmin Su, Yipeng Lan

Institutions: Weifang University of Science and Technology, Guangdong University of Science and Technology, University of Science and Technology Beijing

Language: English

Topic: Microstructure and Mechanical Properties of Steels

Subfield: Mechanical Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $2,830

Funders: National Natural Science Foundation of China, Natural Science Foundation of Shandong Province