Multi-Principal Element Alloys for Concentrating Solar Power Applications

Abstract

Multi-principal element alloys (MPEAs) are characterized by good stability at elevated temperatures, positioning them as a promising alloy family for applications in extreme environments. In particular, their suitability for use in concentrating solar-thermal power (CSP) technology, where exposure to harsh conditions is prevalent, is highly attractive. In this study, the potential of employing MPEAs in components subjected to different environments, including solar salt (composed of 40% KNO3 and 60% NaNO3) at 560 °C, an air atmosphere at 780 °C, and a chloride mixture (46%MgCl2/ 39%KCl/ 15%NaCl) at the same temperature, is investigated. The investigated materials encompass an original -free composition, AlCrFeMoNiTi, and a eutectic composition, AlCoCrFeNi. MPEAs were obtained by arc melting, and their corrosion behavior and stability in the specified environments were thoroughly examined.

Keywords: Multi-Principal Element Alloys, molten salts, CSP, corrosion, HEA, oxidation