TY - GEN
TI - Quantum-mechanical study of magnetic properties of superalloy nanocomposite phase Fe2AlTi
T3 - NANOCON 2017. International Conference on Nanomaterials - Research & Application /9./
AU - Slávik, Anton
AB - The L21-structure Fe2AlTi intermetallic compound is one of the two phases identified in Fe-Al-Ti superalloy nanocomposites. Experimental data related to low-temperature magnetic properties of this Heusler compound indicate that magnetic moment is about 0.1 Bohr magneton per formula unit. In contrast, previous quantum-mechanical calculations predicted Fe2AlTi to have much higher magnetic moment, 0.9 Bohr magneton per formula unit. In order to solve this discrepancy between the theory and experiment we have performed a series of quantum-mechanical fix-spin-moment calculations and compared our results with those for non-magnetic state. It turns out that the total energy of the non-magnetic state is only by 10.73 meV/atom higher than that of the magnetic state. When applying Boltzmann statistics to this very small energy difference we predict that the non-magnetic state appears at non-zero temperatures with significant probabilities (for instance, 22.36 % at T = 100 K) and reduces the overall magnetic moment. As another mechanism lowering the magnetization we studied selected shape deformations, in particular trigonal shearing. Fe2AlTi exhibits a compression-tension asymmetry with respect to these strains and, for example, the strain 0.08 destabilizes the spin-polarized state, leaving the non-magnetic state as the only stable one.
SN - 978-80-87294-81-9
UR - http://hdl.handle.net/11104/0289458
UR - http://www.nusl.cz/ntk/nusl-391445
A2 - Šob, Mojmír
A2 - Friák, Martin
A2 - Miháliková, Ivana
A2 - Všianská, Monika
LA - eng
KW - Nanocomposites
KW - Fixed-spin-moment
KW - Ab initio calculations
KW - Fe-Al based superalloys
PY - 2018
PB - Ústav fyziky materiálů, Žižkova 22, 616 62 Brno, http://www.ipm.cz/
ER -