1Cr18Ni9Ti钢在酸性高锰酸钾去污体系中的腐蚀行为研究

Corrosion behavior of 1Cr18Ni9Ti stainless steel in decontamination system of acidic permanganate solution

采用失重法、金相观察、电子扫描探针观测、电化学阻抗图谱测试等方法,研究了1Cr18Ni9Ti钢在不同浓度KMnO4+10%HNO3清洗条件下的腐蚀行为。结果表明,1Cr18Ni9Ti钢在该体系中发生晶间腐蚀,表面粗糙度增大,且随着KMnO4浓度的提高,腐蚀速度上升。当KMnO4浓度在0.5%时,腐蚀速度近80nm/h,并发现电荷传递电阻下降,金属耐蚀性降低,晶间电阻减小,晶间腐蚀加剧,界面电容提高,金属表面形貌均匀性下降等现象。

With weight loss method, metallurgical observation, SPM and EIS, the corrosion behavior of 1Cr18Ni9Ti steel in washing condition with different concentrations KMnO4 ＋10% HNO3 solution was studied. The results showed that 1Cr18Ni9Ti steel in the system occurred intergranular corrosion, and the surface roughness increased. Meanwhile, with the increase of the concentration of KMnO4, the corrosion rate rose. When the KMnO4 concentration was 0.5%, the corrosion rate was about 80 nm/h, and following phenomena were observed： the charge transfer resistance decreased, the metal corrosion resistance and the intergranular resistance reduced, the intergranular corrosion intensified, the interface capacitance increased, and the uniformity of metal surface topography decreased.