Thermal corrosion behavior of Inconel 693, Hastelloy N and 310S in ceramic waste forming reactions

• Published in: Journal of nuclear materials 2025-01, Vol.603, p.155416, Article 155416
• Main Authors: Ge, Zongyao, Tan, Shengheng, Li, Yingju, Bao, Liangjin, Feng, Xiaohui, Liu, Tianyu, Yang, Yuansheng
• Format: Article
• Language: English
• Subjects: 310S alloy; Nickel-based superalloys; Spent fuel reprocessing; Thermal corrosion behavior
• ISSN: 0022-3115
• DOI: 10.1016/j.jnucmat.2024.155416

•In experimental environment where both molten glass and chloride salts are present, Inconel 693 alloy and 310S alloy exhibit selective corrosion and Hastelloy N alloy is uniform corrosion.•In different corrosion environments, the alloys are subjected to different levels of corrosion due to the encapsulation of sintered products and different levels of gas supply.•Compared to the sintered product region, Inconel 693 alloy forms a more protective spinel layer in the atmosphere region due to a more adequate oxygen supply. The thermal corrosion behavior of Inconel 693, Hastelloy N, and 310S was investigated in the reaction environment of ceramic waste forming reactions. Due to the difference in Cr content and the effect of chlorides, the high Cr Inconel 693 and 310S alloys exhibit selective corrosion by Cr, while the low Cr Hastelloy N exhibits uniform corrosion and the volatilization of MoO3 caused high dimensional losses. The different behavior of the alloys in different corrosive environmental regions is also discussed. In the sintered product region, due to the encapsulation of the sintered product and the corrosion inhibiting role played by O2−, Hastelloy N alloy and 310S alloy experienced milder corrosion compared to alloy in the atmosphere region. And in the atmosphere region, the more abundant gas supply and the open environment caused Hastelloy N alloy and 310S alloy to experience more severe erosion. However, for Inconel 693 alloy, it formed a continuous spinel phase layer containing FeCr2O4 due to the higher partial pressure of O2 in the atmosphere region, resulting in more slight corrosion compared to the sintered product region.