Chemometrics applied to functional chromium electroplating by pulse plating techniques

Abstract

Electrodeposited chromium coatings offer high levels of mechanical and tribological properties that justify their use in many industrial and engineering applications. However, one problem of these functional coatings is their limited corrosion resistance and the low current efficiency of their electrodeposition process. Reverse pulse plating can lead to an improvement in the characteristics of chromium deposits, but the high number of variables involved and the interactions among them make the selection of operating parameters difficult. In this paper, a chemometric approach was used in order to design the experiments and study the effect of pulse plating parameters on the properties of chromium coatings. Multivariate analysis was proposed to establish a relationship among structural and physical characteristics of chromium deposits and to determine the pulse parameters required to achieve certain properties. The results indicated that by reverse pulse electrodeposition, it is possible to obtain crack free chromium coatings, with similar hardness values as those obtained from direct current electrodeposited coatings, but with an improved corrosion resistance.

Keywords:

• Chromium
• Reverse pulse plating
• Chemometrics
• Multivariate
• Principal components

The authors would like to thank IkanKronitek S.L. Company, Gobierno Vasco-Eusko Jaurlaritza (project no. S-PE11UN042) and Ministerio de Ciencia e Innovación of the Spanish government (project no. MAT2011-27380-C02-02) for their financial support. This paper is based on a presentation given at the Fifth European Pulse Plating Seminar, Vienna, Austria, 9 March 2012.