Microstructure and mechanical properties of Fe-Mn based alloys after sub-rapid solidification

The purpose of this paper was to investigate the microstructure and the mechanical properties of Fe-(11, 13 and 17) wt% Mn alloys prepared by using sub-rapid solidification technique. X-ray diffraction showed that α'-martensite with body-centered cubic structure was the major phase formed in the Fe-11 wt% Mn sample, while ε-martensite with hexagonal close-packed structure apparently appeared when Mn content reached to 13. wt.% and its volume percentage increased with the Mn content. The ε-martensite has needle shape and band structure in the Fe-Mn alloy. Mechanical property tests showed that the yield strength decreased while elongation increased as Mn content increased from 11 wt% to 17 wt%. The tensile strength of Fe-13. wt.% Mn sample was found to be the highest among all samples. Addition of 0.14. wt.% carbon could increase tensile strength and elongation of Fe-11 wt% Mn alloy while decrease its yield strength.