Effects of He ion irradiation on the corrosion performance of alloy GH3535 welded joint in molten FLiNaK

Abstract In present study, the influence of He irradiation on the corrosion performance of a GH3535 welded joint has been investigated. A welded joint was irradiated with 300 keV He ions and corroded in FLiNaK molten salt at 700 °C for 400 h. The microstructures after corrosion were characterized by SEM, EPMA and TEM. The corrosion produced cavities and created Cr depletion. He bubbles were formed and grew during corrosion. Although He irradiation did not obviously deteriorate corrosion-induced Cr depletion, the combination effect of He bubbles and corrosion attack caused severe damage to the joint, enlarging bubbles and/or cavities into large holes.