Effect of Mo addition on the microstructure and superelastic properties of Fe-Mn-Al-Ni alloy

Abstract

This study systematically investigated the effect of Mo addition on the microstructure and superelasticity of Fe-Mn-Al-Ni alloy. The findings indicate that the addition of Mo element efficaciously suppressed the formation of γ phase after air cooling. Single crystal samples were prepared through cyclic heat treatment. The size of the precipitates in the solid-solution single crystal was found to be ~ 12.90nm. In contrast, the mean precipitates size in the aging single crystal was ~ 18.07nm. An excellent superelasticity with an average recoverable strain of ~ 8% at an applied strain of ~ 9.5% can be obtained in both the solid solution and aging single crystals with a near [-412] orientation. The Mo addition widens the size range of precipitates with good superelasticity up to ~ 18nm. Additionally, there is a significant difference in the superelastic performance of single crystals with different orientations. Superelastic strain values for orientated single crystals near [-412], [1-20], and [-14-3] were 5.5%, 4.8% and 4.4%, respectively.