Fe2MnSn Heusler Alloy Based Rare-Earth-Free Permanent Magnets

Considering the vast compositional space of Heusler alloys, first-principles-based calculations are ideally suitable for predicting the ground state structure and tailoring the magnetic properties of these alloys. We perform density-functional-theory-based calculations for step-by-step identification of the most stable phase of Fe2MnSn, followed by the calculations of magnetic properties. Ferromagnetic hexagonal phase is identified to be the stable structural phase of Fe
2
MnSn with a large magnetization
$(\mathbf{6.45}\ \mu_{B}/\mathbf{f}.\mathbf{u}.)$
, high Curie temperature (729 K) but with an in-plane magnetic anisotropy. On doping with light interstitial atoms (B, C, H, N and O) an out-of-plane anisotropy can be engineered with enhanced magnetic properties, making this material suitable for permanent magnet applications.