International Conference on Thermo Mechanical Processing - TMP 2026

Effect of Annealing Temperature on Microstructure and Mechanical Properties of High-Mn, High-Al Lightweight Austenitic Steel

Not scheduled

20m

Austria Trend Parkhotel Schönbrunn

Oral Presentation Metallurgical Fundamentals of TMP

Speakers

Mrs Mahsa Barati Mahyari (Materials and Mechanical Engineering, Centre for Advanced Steels Research, University of Oulu, P.O. Box 3000, FIN-90014 Oulu, Finland)Mr Vahid Javaheri (Materials and Mechanical Engineering, Centre for Advanced Steels Research, University of Oulu, P.O. Box 3000, FIN-90014 Oulu, Finland)

Description

In this study, the room temperature tensile and microstructure evolution of a novel cold-rolled lightweight austenitic steel (Fe–19Mn–6Al-4Ni–1C) subjected to different annealing schedules were investigated by transmission and scanning electron microscopy equipped with electron back-scattered diffraction (EBSD) and room temperature tensile test. All experimental samples were furnace annealed under an Ar gas atmosphere at 800°C (S800), 900°C (S900), and 1000°C (S1000) for a holding time of 15 minutes followed by water quench. Microstructural characterization of the processed samples reveals a fully austenitic structure, with the average austenite grain size increasing from 10 µm at 800°C to 30 µm at 1000 °C, respectively. A heterogeneous grain structure obtained at 800°C exhibited an ultrahigh tensile strength of ~1 GPa with an elongation of 45%. The results indicated that multiple deformation mechanisms are involved during the straining of the S800 sample, leading to a simultaneous enhancement of strength and ductility. Increasing the annealing temperature to 1000 °C promoted rapid grain growth, resulting in a significant reduction in tensile strength in S1000 sample.
Keywords: Advanced high-strength steel, Thermomechanical processing, Annealing temperature, Recrystallization, Deformation Twins