Effect of partial austenite reverse transformation process on microstructure and mechanical properties of Fe-8Mn-0.2C-3Al medium Mn steel

doi:10.13251/j.issn.0254-6051.2025.02.014

Abstract

Abstract: Microstructure and mechanical properties of Fe-8Mn-0.2C-3Al medium Mn steel treated by partial austenite reverse transformation (PART) process with two-step annealing were studied by means of field emission scanning electron microscope, X-ray diffractometer and universal testing machine. The results show that for the tested steel treated by PART process with the increase of first step annealing temperature, the austenite content gradually decreases from 49.7% to 21.6%, and the microstructure is lath-like, the yield strength gradually increases, while the tensile strength and elongation gradually decrease. After treated at 755 ℃ for 15 min and 620 ℃ for 30 min, the tested steel obtains optimal mechanical properties, with the tensile strength of 1087 MPa, elongation of 43.4%, and the product of strength and elongation of 47.2 GPa·%, which is attributed to that the moderate austenite stability can fully utilize the TRIP effect during the tensile process and improve the comprehensive mechanical properties of the steel.

Key words: Fe-8Mn-0.2C-3Al medium Mn steel, partial austenite reverse transformation, austenite stability, TRIP effect, mechanical properties

CLC Number:

TG142.1

Liu Mingzhu, Ding Hua, Zou Yuming. Effect of partial austenite reverse transformation process on microstructure and mechanical properties of Fe-8Mn-0.2C-3Al medium Mn steel[J]. Heat Treatment of Metals, 2025, 50(2): 90-95.

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