Evaluating the corrosion performances of wear resistant alloys is important for designing the molten salt-wetted bearings and valves in molten salt reactors. In this study, the corrosion behavior of wear-resistant Tribaloy T-400 alloy (Co-29Mo-8.5Cr-2.8Si) in molten FLiNaK salt (LiF–NaF–KF: 46.5–11.5–42 mol.%), with and without the presence of UNS N10003 alloy, were investigated through static immersion tests at 650°C. After 400hrs corrosion, T-400 alloy showed greater weight loss than UNS N10003 alloy, and the presence of UNS N10003 alloy further increased the weight loss of T-400 alloy. Electron microscopic and salt chemistry analyses showed that Cr and Co were selectively dissolved from T-400 alloy matrix after corrosion, resulting in a porous structure. On the other hand, the Laves phase precipitates were hardly corroded but showed signs of carbide formation on the surface. In addition, when tested with UNS N10003 alloy, some of the Co dissolved from T-400 alloy transferred to the surface of UNS N10003 alloy, hence promoted the corrosion of T-400 alloy. The results have indicated that even T-400 alloy has a relatively low Cr content among high temperature wear-resistant hardfacing alloys, its corrosion resistance is still inadequate in a typical molten salt reactor environment where UNS N10003 alloy and graphite are also present.

评估耐磨合金的腐蚀性能对于设计熔盐反应堆中浸有湿盐的轴承和阀门非常重要。在这项研究中，耐磨的Tribaloy T-400合金（Co-29Mo-8.5Cr-2.8Si）在熔融的FLiNaK盐（LiF–NaF–KF：46.5–11.5–42 mol。％）中的腐蚀行为，以及通过在650°C下的静态浸没试验研究了无UNS N10003合金的情况。腐蚀400小时后，T-400合金的失重比UNS N10003合金大，而UNS N10003合金的存在进一步增加了T-400合金的失重。电子显微镜和盐化学分析表明，Cr和Co在腐蚀后从T-400合金基体中选择性溶解，形成多孔结构。另一方面，Laves相沉淀几乎不被腐蚀，但在表面显示出碳化物形成的迹象。此外，在用UNS N10003合金进行测试时，从T-400合金中溶解的某些Co转移到UNS N10003合金的表面，从而促进了T-400合金的腐蚀。结果表明，即使T-400合金在高温耐磨堆焊合金中具有相对较低的Cr含量，但在还存在UNS N10003合金和石墨的典型熔盐反应堆环境中，其耐腐蚀性仍然不足。