Research progress on influences of alloying elements on mircrostructure and mechanical properties of high-manganese austenitic steels

High-manganese austenitic steel, known for its excellent combination of ultra-high strength and toughness, low magnetic permeability, high fatigue resistance, and low production cost, is widely used in critical industries such as aerospace, petrochemical, and rail transportation. The deformation mechanisms of high-manganese austenitic steel, including martensitic phase transformation, twinning, and dislocation movement, are determined by the stacking fault energy (SFE), which is mainly affected by alloying elements and deformation temperature. This paper systematically reviews the influence of alloying elements such as C, Mn, Si, Nb, Ti, V, Mo, Al, Cr, and rare earth elements on the SFE, microstructure, and mechanical properties of high-manganese austenitic steel. It is concluded that elements including C, Mn, Nb, Ti, and Al increase the SFE, thereby enhancing the elongation after fracture, while Si, Mo, and Cr decrease the SFE, which is more conducive to improving tensile strength. An optimized composition range is recommended as follows: C<0.6%, Mn>18%, 0.3-0.6%Si, 0.29-0.3%Nb, 0-0.15%Ti, 0.15-0.3%V, 0.8-1.3%Mo, 1-3%Cr, and Al<2%. Moreover, the appropriate addition of rare earth elements can purify the molten steel, modify the morphology and distribution of inclusions, refine grains, and inhibit carbide precipitation, thereby further improving the overall mechanical properties of high-manganese austenitic steel. This review provides valuable guidance for the composition design and engineering application of high-manganese austenitic steels and their corresponding welding consumables.