Corrosion studies of SS 316H and Alloy 617 in thermally purified molten NaF‐KF‐UF4‐UF3 salts.

The study investigates salt chemistry and corrosion behavior of SS 316H and Alloy 617 in thermally purified molten NaF‐KF‐UF4‐UF3 salts (UF4/UF3 initial ratio 12–14) at 800°C for 120, 72, and 32 h. UF4/UF3 ratio increases after corrosion tests. Cr species concentration in salts keeps increasing. Fe, Co, Ni, and Mo species increase first, then decrease. Cr/Mn oxides are formed along grain boundaries in SS 316H. Cr near the surface of Alloy 617 is completely depleted. A thin layer composed of Fe, Co, Ni, and Mo is observed on the Alloy 617 surface in 72‐h and 32‐h tests. [ABSTRACT FROM AUTHOR]