Corrosion behavior of 316L and T91 steels in stagnant lead-bismuth eutectic at 550 ℃

Liquid lead-bismuth eutectic (LBE) is an important spallation target material and coolant candidate in accelerator driven sub-critical systems (ADS), and is also a key coolant material for advanced fast reactors. Since LBE has a strong corrosion for structural materials, its application is required to give priority to the problem of compatibility between LBE and structural materials at high temperatures. Experiments were conducted on the corrosion behavior of the two ADS candidate structural materials (316L and T91 stainless steels) in static LBE at 550 ℃ for 1000 h. The microstructure morphology of the etched cross-sections of the samples were characterized by scanning electron microscopy (SEM), and the distribution of the main chemical compositions in the interface of LBE and the matrix was analyzed by energy dispersive spectroscopy (EDS). The results showed that the two samples were subjected to a strong dissolution of the elements and the LBE penetration, and T91 showed a slightly better corrosion resistance to LBE than 316L.