Influence of neutron irradiation and ageing on behavior of SAV-1 reactor alloy

• Main Authors: K.V. Tsay, O.V. Rofman, V.V. Kudryashov, A.V. Yarovchuk, O.P. Maksimkin
• Format: Article
• Language: English
• Published: Elsevier 2021-10-01
• Series: Nuclear Engineering and Technology
• Subjects: SAV-1 aluminum alloy; Neutron irradiation; Fluence; Ageing; Precipitate; Corrosion
• Online Access: http://www.sciencedirect.com/science/article/pii/S173857332100245X

This study observed the effect of neutron irradiation and ageing on the microstructure, hardness, and corrosion resistance of SAV-1 (Al–Mg–Si) alloy. The investigated material was irradiated with neutrons to fluences of 1021–1026 n/m2 in the WWR-K research reactor and kept in dry storage. Long-term irradiation led to an increase in hardness of the alloy and a deterioration of pitting corrosion resistance. Post-irradiation ageing for 1 h at 100–300 °C resulted in a decrease in microhardness of the irradiated SAV-1. The effect of post-irradiation ageing on pitting corrosion was made clear through the formation of Guinier-Preston zones and secondary precipitates in the Al matrix. Ageing at 250 °C corresponded to the development of stable microstructure and the highest corrosion resistance for the irradiated samples. Mg2Si, Si, and needle-shaped β″ precipitates were formed in SAV-1 alloy that was irradiated with low fluences. β″ and clusters of rod-shaped B-type precipitates were observed in highly irradiated samples. The precipitates were similar to those seen in non-irradiated pseudo-binary Al–Mg2Si alloys with Si excess.