Corrosion behavior of Fe-based amorphous alloys in liquid lead-bismuth eutectic at 500°C

Lead-cooled fast reactors (LFRs) represent a key direction of fourth-generation nuclear power technology, where the core challenge lies in the compatibility between structural materials and liquid lead-bismuth eutectic (LBE). At high temperatures, LBE tends to induce severe dissolution and oxidation corrosion in materials, while traditional crystalline alloys are difficult to meet long-term safe service requirements due to the presence of corrosion-sensitive sites, such as grain boundaries and dislocations. Fe-based amorphous alloys, with their unique structure without grain boundaries and dislocations, have demonstrated promising application potential in the field of structural coatings for LFRs. This study systematically investigated the corrosion behavior of two new types of amorphous alloys, Fe 44 Cr 23 W 10 C 13.5 B 7.5 Y 2 (Cr 23 ) and Fe 37 Cr 30 W 10 C 13.5 B 7.5 Y 2 (Cr 30 ), in static LBE at 500°C, and compared with the traditional amorphous alloy Fe 48 Cr 15 Mo 14 C 15 B 6 Y 2 . The results show that the Cr 30 amorphous alloy exhibits the best corrosion resistance, which is mainly attributed to the high Cr and W contents that synergistically promote the formation of a dense corrosion layer of Cr 2 O 3 , Fe(Fe x Cr 1-x ) 2 O 4 , and XWO 4 , enhancing the corrosion resistance of the amorphous alloy against liquid lead-bismuth.