Investigation of Structure of the High-Entropy Alloy Al_0.5CoCrCuFeNi

Abstract

A detailed examination of the structure of the high-entropy alloy Al_0.5CoCrCuFeNi at room temperature was carried out using different methods of optical microscopy, electron microscopy and X-ray structural analysis techniques. Numerical estimates of the dislocation density ∼5⋅10¹⁵ m⁻², the mean size of the ordered (crystalline) domains ~18 nm and lattice micro strain ∼3⋅10⁻³ were obtained through Williamson-Hall analysis of XRD patterns. The estimates of the dislocation density were found to correlate with the estimates of the total length of dislocation segments per unit volume, which effectively interact with elastic vibrations of the sample ∼4⋅10¹³ m⁻², as previously determined from acoustic relaxation measurements. This is consistent with the idea that a significant portion of dislocations are concentrated in grain boundaries, and only dislocation segments located inside grains and having a favourable orientation with respect to the direction of sound wave propagation can effectively interact with cyclic deformation of the sample.

Keywords

High entropy alloy Al_0.5CoCrCuFeNi / Electron microscopy and X-ray structural analysis / Dislocation structure

Acknowledgments

The authors express their sincere gratitude to Damian Szymański for his valuable contribution to this work through the precise elemental composition analysis of the high-entropy alloy (HEA) Al_0.5CoCrCuFeNi. His expertise in spectroscopic techniques and meticulous approach to data acquisition played a crucial role in ensuring the reliability and accuracy of the chemical characterization, which served as a foundation for subsequent structural and microstructural investigations.

Author Contributions

Conceptualization, Y.S. and V.N.; Methodology, Y.S., N.G., D.H. V.Z.; Validation, Y.S., V.N. and E.T.; Formal Analysis, V.Z. and P.Z.; Investigation, Y.S., N.G., D.H., T.B. and I.K.; Resources, N.G. and D.H.; Data Curation, E.T.; Writing—Original Draft Preparation, Y.S.; Writing—Review & Editing, Y.S. and V.N.; Visualization, V.Z. and Y.S.; Supervision, X.X.; Project Administration, Y.S.; Funding Acquisition, V.N. and E.T.

Ethics Statement

Not applicable

Informed Consent Statement

Not applicable

Data Availability Statement

The data presented in this study are available upon request from the corresponding author.

Funding

This work was partly supported by the NRFU (Grant 2023.03/0012); Projects No.0122U001504 and No.0124U000272 NAS of Ukraine and internship within the framework of scientific cooperation between the National Academy of Sciences of Ukraine and the Polish Academy of Sciences.

Declaration of Competing Interest

The authors declare no conflicts of interest.

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