Effect of Vanadium on the Mechanical and Microstructural Properties of Medium-Mn Steels

The automotive industry faces the challenge of enhancing fuel efficiency while meeting global environmental regulations concerning emissions. Thus, advanced high-strength steels (AHSS) recently gained significant attention due to their improved combination of strength and ductility compared to conventional steels, allowing the manufacturing of lighter body-in-white assemblies. Among the AHSS, medium-manganese steels, which contain 3-12 wt% Mn and belong to the third-generation category, are of great interest. Since the mechanical and microstructural properties of medium-manganese steels rely heavily on the amount and stability of retained austenite, the impact of adding vanadium, ranging from 0 to 0.75 wt%, was explored. The results showed that the microstructure of the microalloyed medium-Mn steels consists of martensite and retained austenite phases. The findings also revealed that increasing the vanadium content led to an increase in the proportion of retained austenite coupled with the refinement of austenite grain size.