In this work, the effect of Cu addition on the microstructure and corrosion passivation behavior of Sn alloyed ferritic stainless steel in 3.5 wt.% NaCl solution at 30 °C was investigated by optical microscope (OM), scanning electron microscope (SEM), energy-dispersion spectrum (EDS), potentiodynamic polarization curve and x-ray photoelectron spectroscopy (XPS). The results indicate that Cu addition has certain effect on grain refinement of ferritic stainless steel. Meanwhile, Cu addition has little influence on the cathodic corrosion process of ferritic stainless steel in 3.5 wt.% NaCl solution but shows beneficial effect on enhancing both the corrosion resistance of steel substrate and its passivation behavior. It has been found that the deposition of Cu particles at the bottom of corrosion pits is responsible for the better corrosion resistance and passivation behavior of ferritic stainless steel. Moreover, there is synergistic effect between Sn and Cu on enhancing the corrosion resistance of ferric stainless steel matrix and improving its passivation behavior in NaCl solution.

在这项工作中，通过光学显微镜（OM），扫描电子显微镜（SEM），能量研究了添加Cu对3.5 wt。％NaCl溶液中Sn合金铁素体不锈钢的组织和腐蚀钝化行为的影响，温度为30°C。色散光谱（EDS），电位动力学极化曲线和X射线光电子能谱（XPS）。结果表明，添加铜对铁素体不锈钢晶粒细化具有一定的影响。同时，Cu的添加对在3.5重量％的NaCl溶液中的铁素体不锈钢的阴极腐蚀过程几乎没有影响，但是对增强钢基底的耐腐蚀性和钝化性能均显示出有益的作用。已经发现，在腐蚀坑的底部沉积Cu颗粒是铁素体不锈钢更好的抗腐蚀性和钝化性能的原因。而且，锡和铜之间具有协同作用，以增强铁不锈钢基体的耐腐蚀性并改善其在NaCl溶液中的钝化行为。