Ab initio determination of mechanical and magnetic properties of the hexagonal C14 Laves phase Fe2Ti

Abstract

The Laves phases are topologically compact compounds of stoichiometry A2B, where A and B are elements with very contrasting atomic radii. These phases, although, as precipitates in steels and superalloys, have a deleterious character on the mechanical behavior, present a unique combination of magnetic, thermal, electrical and mechanical properties that make them potential candidates for a series of applications. In particular, the magnetostrictive properties of the Fe2Ti compound, a hexagonal C14 Laves phase, coupled with the properties of the body-centered cubic solid solution (Fe, Ti) with up to 5%at Ti, generated some interest for the manufacture of sheets for cores of electric transformers. In this context, the present project has as objective the determination of information about mechanical and magnetic properties of the Fe2Ti phase. for that purpose, we will use ab initio electronic structure calculations at 0 K, within the scope of the Density Functional Theory (DFT), together with extrapolation methods for finite temperatures. The information obtained using such methodology, in the form of data on total magnetization and magnetization per atom, elastic constants, Young's and shear modulus, Poisson's coefficient, heat capacity, etc., will serve to better characterize and understand the properties of the Fe2Ti phase and, afterwards, to provide data to macroscopic simulations of the material during service in electrical equipment.