Chemical segregation and precipitation at anti-phase boundaries in thermoelectric Heusler-Fe2VAl

Leonie Gomell , Shyam Katnagallu , Abou Diack-Rasselio , Stefan Maier , Loic Perriere , Christina Scheu , Eric Alleno (1) , Baptiste Gault

1 ICMPE - Institut de Chimie et des Matériaux Paris-Est

Fe2VAl exhibits promising properties for thermoelectric applications. Here, we investigated the microstructure of melt spun Fe2VAl using electron microscopy, atom probe tomography and field ion microscopy. We observe platelet-shaped VCxNy precipitates in the vicinity of antiphase boundaries (APB) oriented along the {010}-plane. The mean distance between these precipitates is (140 ± 40) nm. This distance is shorter than the mean free phonon path at room temperature in Fe2VAl, thus, these VCxNy precipitates, combined with the APB may efficiently lower the thermal conductivity of the alloy.

Domaines: Chimie inorganique

Leonie Gomell, Shyam Katnagallu, Abou Diack-Rasselio, Stefan Maier, Loic Perriere, et al.. Chemical segregation and precipitation at anti-phase boundaries in thermoelectric Heusler-Fe2VAl. Scripta Materialia, 2020, 186, pp.370-374. ⟨10.1016/j.scriptamat.2020.04.037⟩. ⟨hal-03051791⟩