Effect of Cr and Mn Addition on the Microstructure, Texture, and Mechanical Properties of Ternary Low-Density Steels

In the present study, the Fe-Al-based compositions developed as low-density steel are subjected to addition of Cr and Mn to increase the elastic modulus. In this regard, Fe-3.7Al-3.1Mn and Fe-6.5Al-6.3Cr steels are produced via melting and casting. The steels are cold-rolled to 98% thickness reduction followed by subsequent annealing at 750 °C. A detailed characterization based on x-ray diffraction and electron back-scattering diffraction shows the stabilization of ferrite phase upon the addition of Cr and Mn with a further reduction in density. The expansion of the lattice is observed after ternary alloying additions. The increase in the yield stress and ultimate tensile strength is noticed upon ternary alloying additions. The Cr and Mn addition also led to an increase in the elastic modulus compared to binary Fe-Al low-density steels.