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Published on: June 18, 2018
Synthesis and Structural Evolution of AgCuCoNiFe High-Entropy Alloy via a Precipitation-Reduction Route
Tomasz Michałek1, Katarzyna Skibińska1, Konrad Wojtaszek1
1Faculty of Non-Ferrous Metals, AGH University of Krakow, Al. Adama Mickiewicza 30, 30-059 Kraków, Poland.
Materials (Basel, Switzerland)
|May 13, 2026
Summary
This study introduces a novel wet-chemical precipitation-reduction method for synthesizing high-entropy alloys (HEAs), demonstrating a viable hydrometallurgical route. While achieving a two-phase AgCuCoNiFe alloy, the method requires further optimization for complete elemental homogeneity.
Area of Science:
- Materials Science
- Metallurgy
- Nanotechnology
Background:
- High-entropy alloys (HEAs) are typically synthesized via high-temperature melting, limiting exploration of alternative fabrication methods.
- Wet-chemical processing offers a potentially more accessible and versatile route for creating complex alloy compositions.
Purpose of the Study:
- To evaluate the feasibility of a precipitation-reduction strategy for synthesizing a two-phase AgCuCoNiFe high-entropy alloy.
- To investigate the structural and compositional evolution of the alloy as a function of thermal reduction time.
Main Methods:
- Co-precipitation of mixed metal carbonates followed by thermal reduction in a reducing atmosphere.
- Quantitative analysis using MP-AES for elemental composition.
- Structural characterization via SEM, EDS, and XRD; microhardness and wettability tests were also performed.
Main Results:
- Efficient co-precipitation achieved a near-equimolar precursor composition.
- As-reduced alloy exhibited surface Ag-enriched heterogeneity, with more uniform bulk composition after abrasion.
- XRD revealed a transition from surface to bulk structure, indicating enhanced alloying internally; moderate hardness (187-221 HV) and hydrophilic behavior (75-83° contact angle) were observed.
Conclusions:
- Precipitation-reduction is a viable hydrometallurgical route for synthesizing multicomponent HEAs, bypassing conventional melting.
- The synthesized AgCuCoNiFe alloy demonstrated two-phase structure and moderate properties.
- Incomplete chemical homogeneity necessitates further optimization of synthesis conditions for uniform alloy composition.
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