Abstract Niobium-stabilised austenitic stainless steel (20Cr-25Ni-Nb) has been immersed in sodium hydroxide, which is used as a corrosion inhibitor. The work shows how NbC precipitates may be degraded by use of pH 13 NaOH. Initial electrochemical measurements indicate that there is no benefit to this pretreatment as regards long-term corrosion inhibition, and post corrosion imaging shows the initiation of pitting corrosion at Nb-rich precipitates still present in the microstructure.

中文翻译：

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氢氧化钠对热敏化 20Cr-25Ni-Nb 奥氏体不锈钢中碳化铌沉淀的影响

摘要 铌稳定奥氏体不锈钢（20Cr-25Ni-Nb）已浸入氢氧化钠中，氢氧化钠用作缓蚀剂。该工作显示了如何使用 pH 值为 13 的 NaOH 降解 NbC 沉淀物。最初的电化学测量表明，这种预处理在长期腐蚀抑制方面没有任何好处，腐蚀后成像显示在仍存在于显微结构中的富 Nb 沉淀物处开始点蚀。