Influence of pulsed current on the aqueous corrosion resistance of electrodeposited zinc

In the present study, the influence of the mode of electrodeposition on the corrosion resistance of zinc (Zn) coating on mild steel substrate has been evaluated. Towards above purpose, Zn coatings were electrodeposited using direct, pulsed and pulse reverse current (PRC). The corrosion resistance was analyzed using electrochemical impedance spectroscopy and potentiodynamic polarization in 3.5% NaCl. The influence of pulse current mode on coating structure and hardness has also been investigated. The results indicate that pulse reverse deposited Zn coatings provide better protection against corrosion. The improved corrosion resistance has been attributed to the microstructure of the PRC coating and also the formation of compact corrosion product.