[T19] High Entropy Alloys

[14D-T19-08] Corrosion Behavior of AlFeCrCoNi and FeCrMoAlTiNi High Entropy Alloys in Molten Solar Salts

*P. Alvaredo Olmos¹, R. Carbajales¹, C. Sobrino² (1.Universidad Carlos III de Madrid, Spain, 2.Universidad Carlos III de Madrid, Spain)

Keywords: High entropy alloy; corrosion resistance; thermosolar; Spark Plasma Sintering.

High entropy alloys are promising for applications involving extreme environmental exposure because of their excellent stability, which they maintain at high temperatures. This work studies the corrosion resistance of AlFeCrCoNi and FeCrMoAlTiNi in molten solar salt and compares it with a reference stainless steel currently used in thermosolar plants. PM processing has been adopted in order to better understand how changes in the microstructure affect the behavior of alloys and to enable more control over the microstructural properties through the use of a fast-sintering technology, Spark Plasma Sintering (SPS). Two combinations of solar salts have been used to monitor the corrosion behavior in molten salts using electrochemical impedance spectroscopy (EIS). The traditional one, a nitride mixture, and a second solar salt made of a chloride mixture proposed because of its higher heat capacity and lower price. The results indicate a promising use of HEA in applications in extreme and corrosive environments.