Corrosion properties of double layer nickel coatings obtained by pulse plating techniques

Abstract

In this study, the influence of pulse plating on the microstructure, morphology and corrosion properties of semibright nickel layers was investigated and it was observed that applied pulse sequences led to deposits with higher corrosion resistance than those obtained by direct current. Moreover, the study of the effect of pulse plated semibright nickel deposits on double layer nickel coatings showed that the applied pulse sequences provoked an increase in potential difference between individual nickel layers, favouring the lateral spread of pitting corrosion and reducing its penetration to substrate. In addition, the influence of the applied pulse sequences on the consumption of the organic additives in the semibright nickel electrolyte was evaluated, observing that this influence was similar to that given by direct current.