Effect of Aging Treatment on Microstructure and Properties of Fe-26Mn-7Al-1.3C Austenitic Steel

Abstract:

The effects of different aging processes on microstructure and properties of Fe-26Mn-7Al-1.3C austenitic steel were investigated by mechanical properties testing, optical microscopy (OM). And scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and transmission electron microscopy (TEM) were also used to study the deposition, morphology and composition of the precipitates. The experimental results showed that after homogenized at 1050°C for 1 h, the best aging process was aged at 550°C for 2 h, then air cooled to room temperature. Through the best heat treatment process, some fine κ-carbides with a modulated structure ((Fe, Mn)₃AlC_x) were found to precipitate within the austenitic matrix, which significantly enhanced the austenitic matrix. Its best comprehensive mechanical properties were tensile strength of 789MPa, yield strength of 612MPa, impact toughness values (V-notch) of 168J/cm², surface hardness of HB272. Nevertheless, as the aging time prolonged, the fine globular κ-carbides became coarse and grew along austenite grain boundaries and were harmful to mechanical properties of the experiment steel.

• Periodical: Materials Science Forum (Volume 850)
• Pages: 554-558
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.850.554
• Online since: March 2016
• Authors: Zhi Dong Tan, Ren Bo Song*, Shi Guang Peng, Lei Chen, Wei Wang, Ke Guo, Zhong Hong Wang
• Keywords: Aging Treatment, Disperse Precipitation, Fe-26Mn-7Al-1.3C Austenitic Steel, κ-Carbide

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