Anodic passive filins formed on Fe60Ni40 in H3BO3-Na2B4O7 buffer solution (pH=9.20) and in H3PO4-Na2HPO4 buffer solution (pH=7.41) have been investigated by XPS. By analysis of the chemical states of elements, components and structure of films,we have probed into the mechanism of the formation of the anodic passive films. In the H3BO3-Na2B4O7 buffer solution (pH=9.20), the formation of passive film was controlled by adsorption of OH-, and the growth of the passive film was a function of passivation potential and time in passive range. The duplex structure, the Fe 、Ni/FeOx、NiO/FeOOH、 Ni(OH)2 was confirmed by detailed peak analysis and profiling. In H3PO4-Na2HPO4 buffer solution (pH= 7.41), the formation of passive film was controlled by competitive react, that is, cations of anodic dissolution reacted with anions such as PO and OH- et al in solution to form compacted deposit films of the phosphate phase.
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