|About this Abstract
||2020 TMS Annual Meeting & Exhibition
||Characterization of Minerals, Metals and Materials
||Epsilon to Tau Phase Transformation in MnAl Alloys
||Ozgun Acar, Merve Genc Unalan, İlkay Kalay, Yunus Kalay
|On-Site Speaker (Planned)
Magnetic materials play a critical role in devices for the conversion, transmission and energy storage. There is a growing demand for NdFeB permanent magnets with high coercivity and magnetic flux. While magnets are increasingly dependent upon rare-earths (RE), there has been an effort to minimize or substitute their use. In this regards, we studied RE-free MnAl alloys. Magnetism in MnAl alloys derives from a ferromagnetic metastable tau-phase. In order to improve the magnetic properties, epsilon-to-tau transformation should be well established. In this study, we conducted microstructural, thermal and crystallographic analysis of this phase transformation in details. XRD studies were conducted in-situ using synchrotron radiation. Epsilon-to-tau transformation is found to be dependent on ordering of the epsilon-phase and can only proceed with epsilon-prime phase. As Mn content increases compositional ordering do not take place and stable phases form. The corresponding magnetic properties with respect to phase transformation characteristics will be discussed.