Effect of partitioning time on microstructure and properties of low carbon hot rolled F-Q&P steel

doi:10.13251/j.issn.0254-6051.2022.09.005

Abstract

Abstract: Using a two-high reversing mill, effect of partitioning time of the relaxation-quenching partition (F-Q&P) process on microstructure and mechanical properties of tested steel was studied. The results show that under the relaxation-quenching partitioning (F-Q&P) process, the microstructure of the tested steel is mainly composed of polygonal ferrite, lath martensite and retained austenite. When the partitioning time is prolonged, the strength of the tested steel decreases, the yield ratio first decreases and then increases, the elongation increases, and the hardening index n value and the retained austenite content first increase and then decrease. After partitioning for 60 s, the tested steel has the lowest yield ratio and highest n value, 0.62 and 0.12, respectively, and the tensile strength and elongation are 1090 MPa and 19.0%, respectively, the mechanical properties are optimum.

Key words: F-Q&P process, partitioning time, polygonal ferrite, retained austenite, deformation substructure

CLC Number:

TG156

Su Zhangzhu, Wu Run, Li Zhao, Wu Teng, Qin Jinzhu. Effect of partitioning time on microstructure and properties of low carbon hot rolled F-Q&P steel[J]. Heat Treatment of Metals, 2022, 47(9): 27-30.

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