Preparation and characterization of nanocrystalline Fe-Ni-Cr alloy electrodeposits on Fe substrate

摘要

Fe-Ni-Cr alloy layers were prepared by electrodeposition from trivalent chromium plating bath in chloride-sulfate based solution. The influences of bath composition and plating parameters on the alloy electrodeposition process and the properties of deposited alloy were studied. The effects of plating parameters and bath composition such as current density, bath pH, bath temperature, the concentrations of FeSO4 center dot A 7H(2)O and CrCl3 center dot A 6H(2)O on the contents of Fe and Cr in Fe-Ni-Cr alloy layer were investigated. Electrodeposited Fe-Ni-Cr alloy layers on Fe substrate were characterized by X-ray diffraction (XRD), Electronic Differential System (EDS) and a CHI600B electrochemistry workstation. The composition of the Fe-Ni-Cr coatings depends on bath composition and plating conditions including pH, current density, and temperature. The internal structure of the alloy is nanocrystalline, the average grain size is 87 nm, and the corrosion resistance of the alloy layers is better than that of pure nickel layers.