Retained Austenite Control and Extra-Cryogenic Impact Toughness of Fe-3.0%Mn Low Carbon Steel

Abstract:

The control of the retained austenite in Fe-3.0%Mn Low carbon steel by a three-step intercritical heat treatment and the low-temperature impact toughness evolution during the process were analyzed in the present study. The results indicated that the microstructure consisted intercritical ferrite, martensite/bainite and retained austenite. The distribution of carbon and manganese could improve the stability of the austenite located at the grain boundaries of prior austenite and lath boundaries of martensite. For the TRIP effect of the austenite, the excellent plasticity and low temperature toughness was obtained. The impact toughness could reach 200 J (impact energy) at －80 °C during the three-step heat treatment, and the uniform elongation could exceed at 16%.

• Periodical: Materials Science Forum (Volume 993)
• Pages: 520-525
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.993.520
• Online since: May 2020
• Authors: Xiang Tao Deng*, Xiao Lin Li, Long Huang, Zhao Dong Wang
• Keywords: Cryogenic Impact Toughness, Intercritical Heat Treatment, Medium Manganese Steel, Retained Austenite

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