Effect of Micro-Alloyed/Alloyed Elements on Microstructure and Properties of Fe-Mn-Al-C Lightweight Steel

In the 14th Five Year Plan, China clearly proposes to develop the automobile strategic industry, reduce the carbon emission intensity, and formulates the carbon emission peak plan by 2030. As the automobile is the most frequently used vehicle, weight reduction can achieve the purpose of energy-saving and emission reduction and help to achieve the peak of carbon emissions as soon as possible. The lightweight automobile steel is the research hotspot in the future, and the lightweight steel has attracted much attention in the automobile manufacturing industry. Fe-Mn-Al-C lightweight steel, with its high strength, good oxidation resistance at high temperatures, good fatigue performance, high elongation, and good energy absorption during a collision, etc., has attracted the attention of researchers in the field of automotive steel. It is found that the addition of micro-alloyed/alloyed elements to Fe-Mn-Al-C lightweight steel is of great significance to improve its properties. In this paper, the effects of micro-alloyed elements (Nb and V) and alloy elements (Si, Cr, and Cu) on the microstructure, properties, and kappa-carbide of Fe-Mn-Al-C lightweight steel were reviewed. The main ways of improving the properties of Fe-Mn-Al-C lightweight steel by micro-alloyed/alloyed elements were summarized and the existing problems were analyzed to provide a reference for future research.