Effect of partitioning temperature on microstructure and mechanical properties of 0.2C-2.96Mn-1.73Si steel

doi:10.13251/j.issn.0254-6051.2022.06.009

Abstract

Abstract: Multiphase structure composed of ultrafine ferrite, martensite and retained austenite was obtained in 0.2C-2.96Mn-1.73Si steel by intercritical heating quenching and partitioning (IQP) heat treatment. The effect of partitioning temperature on microstructure and mechanical properties of the tested steel was researched by means of SEM, XRD and tensile testing machine. The results show that with the increase of partitioning temperature, the tensile strength of the tested steel gradually decreases, and the yield strength and elongation first increase and then decrease. The content of retained austenite in the steel first increases and then decreases with the increase of partitioning temperature. The volume fraction of retained austenite is the highest when the partitioning temperature is 400 ℃, the tested steel has the highest uniform deformability because lasting work hardening can be provided by TRIP effect, and displays excellent comprehensive mechanical properties with ultimate tensile strength of 1444 MPa, elongation of 20.13% and the product of strength and elongation of 29 GPa·%.

Key words: IQP process, partitioning temperature, retained austenite, mechanical properties

CLC Number:

TG142.1

Feng Shuming, Wan Decheng, Hu Jinpeng, Li Jie. Effect of partitioning temperature on microstructure and mechanical properties of 0.2C-2.96Mn-1.73Si steel[J]. Heat Treatment of Metals, 2022, 47(6): 54-58.

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