Long-term corrosion of austenitic steels in flowing LBE at 400 °C and 10 −7 mass% dissolved oxygen in comparison with 450 and 550 °C

Abstract Long-term corrosion tests for up to ∼13,194 h on 1.4970 (15-15 Ti), 316L and 1.4571 austenitic steels were carried out at 400 °C in flowing LBE (2 m/s) with 10 −7 mass% dissolved oxygen. The steels show general slight oxidation (Cr-based oxide film) along with local, pit-type solution-based corrosion attack. The incubation time for pit-type attack is ∼4500 h. After ∼13,194 h, the maximum pit depth observed was ∼14, 23 and 57 μm for 1.4970, 316L and 1.4571, respectively, that corresponds to local corrosion rates of ∼6, 10 and 26 μm/year. At 450 °C and 550 °C, the corrosion rates are ranged in between ∼120−220 μm/year and ∼500–3000 μm/year, respectively. Corrosion appearances and mechanisms are discussed.