Effect of oxygen concentration and temperature on compatibility of ODS steel with liquid, Stagnant Pb45Bi55

Exposure tests of an oxide dispersion strengthened martensitic type steel (ODS) were performed in stagnant lead bismuth eutectic (LBE) containing 10−4, 10−6 and 10−8 wt% of oxygen at 500–650 °C up to 10 000 h. It resulted that the base metal was protected from corrosion by the formation of a magnetite and spinel layer in liquid Pb45Bi55 containing 10−6 wt% of oxygen at 550 °C or less, not however, at higher temperatures. At 650 °C and 10−8 wt% of oxygen, the ODS steel showed good compatibility with LBE by formation of a thin mixed high chromium spinel layer, while at 10−4 wt% multilayers of magnetite and spinel develop at this temperature which break off but are renewed by oxide layers which protect the steel again.