Experimental investigation of the local environment and lattice distortion in refractory medium entropy alloys

Lola Lilensten (1) , Karine Provost (2) , Loïc Perrière (2) , Emiliano Fonda (3) , Jean-Philippe Couzinié (2) , Fabienne Amann (1) , Martin Radtke (4) , Guy Dirras (5) , Ivan Guillot (2)

1 IRCP - Institut de Recherche de Chimie Paris
2 ICMPE - Institut de Chimie et des Matériaux Paris-Est
3 SSOLEIL - Synchrotron SOLEIL
4 BESSY II
5 LSPM - Laboratoire des Sciences des Procédés et des Matériaux

EXAFS analysis of pure elements, binary and ternary equiatomic refractory alloys within the Nb-Zr-Ti-Hf-Ta system is performed at the Nb and Zr K-edges to analyze the evolution of the chemical local environment and the lattice distortion. A good mixing of the elements is found at the atomic scale. For some compounds, a distribution of distances between the central atom and its neighbors suggests a distortion of the structure. Finally, analysis of the Debye-Waller parameters show some correlation with the lattice distortion parameter δ², and allows to quantify experimentally the static disorder in medium entropy alloys.

Domaines: Matériaux; Matière Condensée [cond-mat]

Lola Lilensten, Karine Provost, Loïc Perrière, Emiliano Fonda, Jean-Philippe Couzinié, et al.. Experimental investigation of the local environment and lattice distortion in refractory medium entropy alloys. Scripta Materialia, 2022, 211, pp.114532. ⟨10.1016/j.scriptamat.2022.114532⟩. ⟨hal-03544393⟩