Corrosion of Zr-xTi-yNb alloys in concentrated nitric acid at elevated temperature

Corrosion-resistant alloys are essential for reprocessing the spent nuclear fuel in concentrated HNO₃ at elevated temperature. Herein, 14 Zr-xTi-yNb alloys were fabricated to reveal the effects of Ti and Nb on their long-term corrosion behaviors. Zr-1.0Ti-0.5 Nb alloy achieves a prominently low corrosion rate of < 0.0003 mm/a in 12 M HNO₃ at 95 ℃ for 1000 h, contributed to the moderate Ti which strengthens the passivation and Nb which enhances the stability of the protective oxides. This work offers new insights into Zr alloys’ design and their corrosion mechanism for reprocessing dissolver of spent nuclear fuel.