电沉积铁镍合金纳米晶薄膜微结构与耐蚀性能

Relationship between microstructure and corrosion resistance of electrodeposited nano-crystal Fe-Ni alloy film

采用电沉积方法从硫酸盐体系镀液中制备3种纳米级Fe-36Ni、Fe-44Ni、Fe-80Ni合金薄膜,应用原子力显微镜(AFM)、X射线衍射仪(XRD)、中性盐雾试验和电化学测量技术对三种Fe-Ni合金薄膜的微观结构和耐蚀性能进行了研究.结果表明,3种纳米Fe-Ni合金薄膜的耐腐蚀性能与合金的微观结构密切相关,具有单一γ相结构的Fe-80Ni耐蚀性能最好,由α-(Fe,Ni)相和γ-(Fe,Ni)相组成的混合固溶体Fe-44Ni次之,而含有单相铁、α-(Fe,Ni)相和γ-(Fe,Ni)相的混合固溶体Fe-36Ni合金最差,这是由于合金薄膜中各相电化学稳定性存在显著差异所致.

Three nanocrystalline alloy thin films,Fe-36Ni,Fe-44Ni and Fe-80Ni,were prepared in sulphate bath by electrodeposition.Atomic force microscopy,X-ray diffraction spectroscopy,neutral salt spray and electrochemical measurement were used to investigate the microstructure and corrosion resistance of as-prepared Fe-Ni alloy thin films.Results showed that the corrosion resistance of three thin films was closely associated with their intrinsic microstructures.The corrosion resistances were in the following order：Fe-80Ni with single γ-（Fe,Ni） solid solution phase Fe-44Ni composed of the mixed solid solution phase of α-（Fe,Ni） and γ-（Fe,Ni） Fe-36Ni with single ferrous phase and the mixed phase of α-（Fe,Ni） andγ-（Fe,Ni）.The corrosion resistance was assigned to the different electrochemical stability of different phases and the surface effect of nano-materials.