Corrosion Behavior of Commercial FeCrAl and TiAl Alloys in Molten Pb With 2E‐7 wt% Oxygen at 600°C and 700°C

ABSTRACT

Liquid lead (Pb) is an attractive heat transfer fluid for advanced thermal energy storage (TES) systems. In the search for adequate structural materials that withstand the corrosive nature of liquid Pb at high temperature, Al‐containing materials might offer excellent corrosion resistance due to their ability to form protective alumina scales. This study investigates the corrosion behavior of two commercial ferritic FeCrAl alloys, Kanthal APM and Kanthal APMT, and two titanium aluminides, TNM‐B1 and GE 48‐2‐2, in liquid Pb under conditions relevant for TES systems. Exposure tests are performed in liquid Pb with 2E‐7 wt.% dissolved oxygen at 600°C and 700°C for up to 5000 h. Examination of the specimens after exposure shows the formation of stable and protective oxide scales at 600°C on all materials, while exposure at 700°C leads to various failure mechanisms, ranging from internal oxidation for APM to severe Pb penetration for TNM‐B1 and GE 48‐2‐2.