Effect of tempering temperature on microstructure and properties of ultra low carbon 7%Mn steel

doi:10.13251/j.issn.0254-6051.2021.10.029

Abstract

Abstract: Microstructure and mechanical properties of the ultra low carbon medium manganese steel after quenching and tempering at different temperatures were studied, and the amount of reversed austenite in the tested steel before and after low temperature treatment (－60 ℃, -80 ℃ and －100 ℃) was measured by means of XRD. Based on this, the effect of reversed austenite content and thermal stability on mechanical properties of the tested steel was analyzed. The results show that higher temperature tempering promotes the formation of reversed austenite, in which the austenite stabilizing elements are quickly enriched. Meanwhile the austenite obtained at higher tempering temperature is more distributed between the coarsened martensitic laths, which makes the austenite have high stability. Due to the more reversed austenite in the tested steel, the TRIP effect is more significant in the process of deformation, which promotes the improvement of low temperature toughness and plasticity of the tested steel.

Key words: ultra low carbon 7%Mn steel, reversed austenite, low temperature toughness

CLC Number:

TG162.83

Yang Yuehui, Yuan Shaoqiang, Liang Guoli, Wang Zhu. Effect of tempering temperature on microstructure and properties of ultra low carbon 7%Mn steel[J]. Heat Treatment of Metals, 2021, 46(10): 168-172.

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