Mechanical and high-temperature corrosion properties of AlTiCrNiTa high entropy alloy coating prepared by magnetron sputtering for accident-tolerant fuel cladding

Abstract

A high-entropy alloy (HEA) AlTiCrNiTa coating with near-equal molar ratio was prepared on the base of zircaloy-4 substrates using radio frequency (RF) magnetron sputtering (MS) technology. The microstructure, mechanical properties and surface wettability were systematically investigated. Moreover, the corrosion property of the coating was studied after a 45-day autoclave test. The results indicate that structure of the AlTiCrNiTa HEA coating is almost amorphous with some FCC nano-crystallized domains and the coating has a high hardness of 18.34 GPa. After 45-day autoclave test, AlTiCrNiTa HEA coating still effectively protected the Zr-4 substrate from oxide. The mechanism of the corrosion process of the HEA AlTiCrNiTa coating was evaluated in detail.