In this paper, the influence of metal salt ratio on the plating rate, composition, and structure of Ni-Fe-P films deposited by chemical process from sulphate bath was investigated. Gravimetric and electrochemical measurements, SEM, XRD were applied to characterize the films. The weight of Ni-Fe-P film increases near linearly with the plating time. The deposition potential shifts to negative direction and the plating current decreases with the increase of FeSO4, when the total concentration of the metal salts is fixed in bath. Increasing the FeSO4 concentration also causes an increase in the polarization resistances, indicating the FeSO4 has an inhibition effect on the chemical process. The plating current derived in the complete bath is higher than that determined from the simulation half-reaction cells due to the interaction between the two half reactions. It is found that the ratio of FeSO4/(NiSO4+FeSO4) affects the composition of Ni-Fe-P film, leading to the structure change of the film.
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