High-Entropy Alloy Coatings and Corrosion Properties

High-entropy alloys (HEAs) are multicomponent metallic systems typically comprising five or more principal elements in near-equiatomic proportions. Their high configurational entropy promotes simple solid-solution phases, often face-centred cubic (FCC) or body-centred cubic (BCC), which confer excellent mechanical strength, thermal stability and chemical homogeneity. When applied as coatings, HEAs form dense, adherent films that resist aggressive environments by combining multiple corrosion-resistant elements and promoting the formation of stable passive oxide films. Key factors influencing corrosion performance include the alloy’s phase constitution, grain size, surface morphology and the chemistry of the passive layer. Tailoring deposition methods, heat treatments and composite formulations enables optimisation of barrier properties, making HEA coatings attractive for marine, chemical and energy applications where prolonged protection against pitting, uniform attack and erosion is required.

Research from Nature Portfolio

Recent studies have explored novel synthesis routes to generate nanostructured HEA materials with potential in protective coatings. A pioneering sol-gel autocombustion approach produced CoCrCuNiAl alloys with an average grain size of around 14 nm and uniform dispersion of constituent elements. The ultrafine microstructure enhances passive film development and suggests promise for thin-film barrier applications. In another foundational work, multicomponent HEA nanoparticles were decorated onto few-layer graphene by mechanical milling and sonication. Electrochemical impedance spectroscopy and potentiodynamic tests in chloride media demonstrated superior corrosion resistance compared with milled or exfoliated graphene alone, indicating that HEA–graphene composites can serve as advanced anti-corrosion coatings with synergistic barrier and electronic effects.

High-Entropy Alloy Coatings and Corrosion Properties publication trend

The graph below shows the total number of articles in high-entropy alloy coatings and corrosion properties across all publications each year (not limited to Nature Index journals).

Technical terms

High-entropy alloy (HEA): A metallic system containing multiple principal elements in near-equiatomic ratios, stabilised by high configurational entropy.

Passive film: A thin, protective oxide layer that forms spontaneously on certain alloys, inhibiting further corrosion.

Potentiodynamic polarisation: An electrochemical technique measuring current response as the electrode potential is swept, used to assess corrosion kinetics.

Electrochemical impedance spectroscopy (EIS): A method that applies an alternating potential to characterise the resistive and capacitive behaviour of coatings and interfaces.

References

1. Sol-gel Autocombustion Synthesis of Nanocrystalline High-entropy Alloys. Scientific Reports (2017).
2. First Report on High Entropy Alloy Nanoparticle Decorated Graphene. Scientific Reports (2018).
3. Electrodeposition, Characterization, and Corrosion Behavior of CoCrFeMnNi High-Entropy Alloy Thin Films. Coatings (2021).
4. Influence of Heat Treatment on the Corrosion Behavior of Electrodeposited CoCrFeMnNi High-Entropy Alloy Thin Films. Coatings (2022).
5. Phase composition, surface chemistry and electrochemical studies of electrodeposited AlMnFeCuNi high entropy alloy composite coatings incorporated with carbon nanotubes. Materials Research Express (2024).
6. Electrochemical Deposition and Corrosion Resistance Characterization of FeCoNiCr High-Entropy Alloy Coatings. Coatings (2023).