A Preliminary Study on Wear Resistance and High-Temperature Steam Oxidation of AlCrFeMoZr High-Entropy Alloy Coatings for Accident-Tolerant Fuel

High-entropy alloy (HEA) coatings have attracted significant attention in the nuclear power field due to their exceptional properties, showing great potential for accident-tolerant fuel (ATF) applications. In this study, novel AlCrFeMoZr HEA coatings with a near-equal molar ratio were successfully fabricated via magnetron sputtering at different bias voltages (−50 V, −100 V, and −150 V). The influence of bias voltage on the microstructure and mechanical properties of the coatings was systematically investigated. The results reveal that all HEA coatings exhibit a body-centered cubic structure with a (110) preferential orientation. As the bias voltage increased, the Al content in the HEA coating decreased, and the microstructure coarsened. The microhardness and friction and wear test results demonstrate that an HEA coating deposited at −100 V exhibited optimal mechanical properties owing to its good balance between hardness and toughness, leading to an improved tribological performance. Furthermore, a high-temperature water vapor oxidation experiment was conducted at 1200 °C in order to preliminarily study the differences in the anti-oxidation behavior of the new composition, an AlCrFeMoZr HEA coating, when deposited at various biases.