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arXiv · 2106.12957

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

Lola Lilensten·Karine Provost·Loïc Perrière·Emiliano Fonda·Jean-Philippe Couzinié·Fabienne Amann·Martin Radtke·Guy Dirras·Ivan Guillot
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Abstract

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 $δ^2$, and allows to quantify experimentally the static disorder in medium entropy alloys.

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Lola Lilensten, Karine Provost, Loïc Perrière, Emiliano Fonda, Jean-Philippe Couzinié, Fabienne Amann, Martin Radtke, Guy Dirras, Ivan Guillot. 2022-01-26. Experimental investigation of the local environment and lattice distortion in refractory medium entropy alloys. https://doi.org/10.1016/j.scriptamat.2022.114532.

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