Effect of intercritical temperature on microstructure and mechanical properties of medium manganese steel after IQ&P treatment

doi:10.13251/j.issn.0254-6051.2020.07.008

Abstract

Abstract: Effect of intercritical temperature on the microstructure and mechanical properties of IQ&P treated 0.1C-7Mn steel was investigated by means of scanning electron microscope and room temperature tensile testing. The results show that the mechanical properties of the steel first increase and then decrease with intercritical temperature increasing. When the intercritical temperature is 660 ℃, the mechanical properties of the steel are optimal, with the strength-elongation product reaching the maximum of 21.2 GPa·%. When the IQ&P process is carried out at higher and lower intercritical temperature, there is no martensite transformation due to the high stability of the retained austenite. In addition, when the intercritical temperature is 660 ℃, there is a clear yield platform in the tensile stress-strain curve, while it disappears when the intercritical temperature goes higher.

Key words: medium manganese steel, intercritical temperature, IQ&, P process, retained austenite, mechanical properties

CLC Number:

TG142.31

Tian Yaqiang, Cao Zhongqian, Pan Hongbo, Song Jinying, Zheng Xiaoping, Chen Liansheng. Effect of intercritical temperature on microstructure and mechanical properties of medium manganese steel after IQ&P treatment[J]. Heat Treatment of Metals, 2020, 45(7): 37-41.

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