In this study, the corrosion characteristics of essential materials used in supercritical water-cooled reactors (SCWRs) were investigated. Austenitic stainless steels 304 SS and 316 SS and nickel-based alloys 625 and 800 were exposed to supercritical water (SCW) at 500 °C and 25 MPa. The results showed that 304 SS, 316 SS, and Alloy 800 formed a double oxide layer, with the outer and inner layers enriched in Fe and Cr/Ni, respectively. Alloy 625 formed outer Ni-rich oxides (mainly NiO) and inner Cr-rich oxides and Ni-Cr oxides (mainly Cr₂O₃ and NiCr₂O₄, respectively). The results indicated that the difference in the protective performance of the corrosion products was mainly due to the Cr content, and the order of corrosion resistance was Alloy 625 > Alloy 800 > 304 SS > 316 SS. In addition, a corrosion mechanism model was established, which lays a good foundation for corrosion prediction and protection in SCWRs.

在这项研究中，研究了超临界水冷堆（SCWR）中使用的基本材料的腐蚀特性。将奥氏体不锈钢 304 SS 和 316 SS 以及镍基合金 625 和 800 暴露于 500 °C 和 25  MPa 的超临界水 (SCW) 中。结果表明，304 SS、316 SS 和 Alloy 800 形成了双层氧化层，外层和内层分别富含 Fe 和 Cr/Ni。合金625形成外部富Ni氧化物(主要是NiO)和内部富Cr氧化物和Ni-Cr氧化物(分别主要是Cr ₂ O ₃和NiCr ₂ O ₄ )。结果表明，腐蚀产物防护性能的差异主要是由Cr含量决定的，耐腐蚀性能顺序为合金625>合金800>304SS>316SS。此外，建立了腐蚀机理模型，为超临界水堆腐蚀预测和防护奠定了良好的基础。