Phase separation in Fe2CrSi thin films

TL;DR

This study investigates the phase separation behavior of Fe2CrSi thin films, revealing their decomposition into Fe3Si and Cr3Si phases upon heat treatment, supported by experimental and ab initio computational analysis.

Contribution

It provides new insights into the phase stability and decomposition mechanisms of Fe2CrSi alloys in thin film form, combining experimental deposition with theoretical calculations.

Findings

Fe2CrSi decomposes into Fe3Si and Cr3Si phases after heat treatment.

Decomposition is energetically favorable according to ab initio calculations.

The resulting phases are nearly epitaxial with specific crystal structures.

Abstract

Thin films of a nominal Fe2CrSi alloy have been deposited by magnetron co-sputtering with various heat treatments on MgO and MgAl2O4 substrates. After heat treatment, the films were found to decompose into a nearly epitaxial Fe3Si film with the D0$_3$ structure and Cr3Si precipitates with the A15 structure. We explain the experimental results on the basis of ab initio calculations, which reveal that this decomposition is energetically highly favorable.