Electrochemical corrosion resistance study of electroplated nickel/copper coatings obtained by pulsed current

Abstract

Abstract

In this work were obtained nickel-copper coatings on Zamak by electro- deposition using inverse-pulsed current, direct-pulsed current and direct

current techniques, with the purpose of studying the corrosion behavior

of each technique in a saline environment (3,5%wt. NaCl). Through the

analysis of the Tafel polarization curves it was found that the corrosion

rate of the coatings obtained by direct current technique are higher than
the

corrosion

rate

of

the

coatings

obtained

by

inverse-pulsed

current

technique. The Electrochemical Impedance Spectroscopy (EIS) allowed

fnding the electric model of the solution-coating

interface. The results

showed that pulsed current techniques generate deposits that

increase

the corrosion resistance of obtained coatings.