Coherent precipitation and stability of cuboidal nanoparticles in body-centered-cubic Al0.4Nb0.5Ta0.5TiZr0.8 refractory high entropy alloy

doi:10.1016/j.scriptamat.2020.08.029

Scripta Materialia

Volume 190, 1 January 2021, Pages 40-45

https://doi.org/10.1016/j.scriptamat.2020.08.029 Get rights and content

Abstract

The present work developed a new body-centered-cubic (BCC)-based Al_0.4Nb_0.5Ta_0.5TiZr_0.8 refractory high entropy alloy with coherent precipitation. The formation of cuboidal nanoprecipitates with a size of 25~50 nm in an 873 K-aged alloy is ascribed to a moderate lattice misfit. A Zr₅Al₃ phase also coexists with B2 in a same particle shape due to similar chemical compositions, in which Ti is enriched in B2 but not in Zr₅Al₃. The BCC/B2 coherency would be deteriorated with increasing the aging temperature, leaving coarse Zr₅Al₃ alone. Besides, there exist two kinds of BCC phases due to the segregations of Nb/Ta and Ti/Zr.

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Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.The authors declare the following financial interests/personal relationships which may be considered as potential competing interests

Acknowledgements

It was supported by the National Natural Science Foundation of China [91860108], Natural Science Foundation of Liaoning Province of China (2019-KF-05-01), and the Fundamental Research Funds for the Central Universities (DUT19LAB01) .

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Coherent precipitation and stability of cuboidal nanoparticles in body-centered-cubic Al0.4Nb0.5Ta0.5TiZr0.8 refractory high entropy alloy

Abstract

Graphical abstract

Section snippets

Declaration of Competing Interest

Acknowledgements

Acta Mater.

Prog. Mater. Sci.

Mater. Sci. Eng. A

Mater. Lett.

Mater. Des.

J. Alloys Compd.

J. Alloys Compd.

Mater. Des.

Acta Mater.

Scripta Mater.

Acta Mater.

Acta Mater.

Acta Mater.

Materialia

Materialia

Scripta Mater.

Acta Mater.

Scripta Mater.

Coherent precipitation and stability of cuboidal nanoparticles in body-centered-cubic Al_0.4Nb_0.5Ta_0.5TiZr_0.8 refractory high entropy alloy