Effect of current density and pH in obtaining the Ni-Fe alloy by electrodeposition

ABSTRACT

Metallic coatings can be applied for different purposes, for example to improve the mechanical, catalytic, anticorrosive properties or simply to improve the decorative appearance. In the work the Fe-Ni alloys have been obtained by electrodeposition process using a simple electrolytic bath containing the reagents, nickel sulfate, iron sulfate and sodium tartrate. A complete experimental design 2², associated with the response surface methodology (RSM) technique was used as optimization tool. Chemical composition, current efficiency, surface morphology and electrochemical corrosion measures were performed. It was observed that a decrease in the pH favored an increase in iron and decrease in nickel contents in the alloy. The iron content influenced the alloy morphology. The best experiment showed an average corrosion resistance 5471.5 Ω.cm² and a corrosion current density 4.814x10^-6 A/cm². This experiment presented a composition of 70 wt% Ni and 30 wt% Fe in the alloy and an average deposition current efficiency of 58.7%.

Keywords:
Ni-Fe alloy; Electrodeposion; Corrosion; Experimental Design