Microstructure, mechanical properties and high temperature corrosion of [AlTiCrNiTa/(AlTiCrNiTa)N]20 high entropy alloy multilayer coatings for nuclear fuel cladding

[AlTiCrNiTa/(AlTiCrNiTa)N]20 multilayer coatings were prepared by magnetron sputtering on Zr-4 substrate. The mechanical properties, microstructure and wettability of multilayer coatings were systematically studied by SEM, nano indentation instrument, scratch instrument and contact Angle instrument. In addition, after high temperature oxidation corrosion for 45 days, the coating was characterized by SEM and XRD. Al in the coating was wrapped in dense spinel NiCr2O4, which inhibits layer by layer dissolution of the coating, thus improving the corrosion resistance of the coating. The corrosion mechanism of [AlTiCrNiTa/(AlTiCrNiTa)N]20 multilayer coatings was evaluated in detail.