Temperature dependent mechanical properties of MAB phase Fe2AlB2

Abstract

As a new type of laminate materials, the MAB phase Fe2AlB2 is attractive due to its near-room magnetocaloric properties. In this work, we propose the energy-strain approach to the elastic constants of MAB phase Fe2AlB2. The quasi-static approximation in combination with first-principles calculations is used to study the magnetic and elastic properties of Fe2AlB2 at finite temperature (0–1300K). Our temperature dependent polycrystalline moduli have similar tends to experiments, due to the proper approximation to the paramagnetic state above room temperature. Both the lattice parameters and elastic constants show the strong anisotropy in a range of 0–1300K. Although only Fe atoms contribute the magnetic property, their local magnetism plays a key role in the phase stability and the temperature dependent mechanical properties of Fe2AlB2.