The Effect of Dispersion Phases of SiC and Al2O3 on the Properties of Galvanic Nickel Coatings

Abstract

In this study, Ni, Ni-SiC and Ni-Al2O3 coatings were electroplated on the 2xxx series aluminium alloy. The following parameters of the electroplating process were applied: current density -4A/dm 2 , time -60 minutes, and temperature -60°C. Hard particles of submicrometric size were used. The results of the research showing the effect of the addition of hard particles (introduced into the nickel bath as a dispersed phase) on the properties of coatings, including the effect of the type (SiC or Al2O3) and content (0, 25, 50 g / l) of these particles, were discussed. Based on extensive investigations, it was found that the type of ceramic particles significantly affects the structure of produced coatings. The dispersed particles incorporated into the nickel coatings improve their abrasion resistance. Improving of the corrosion properties were observed only in the case of coatings containing silicon carbide particles.

Archives of Metallurgy and Materials

“…The processes of the deposition of coatings were carried out with multi-component Watts solutions containing: nickel sulphate (source of Ni 2+ ions), nickel chloride (improvement of bath conductivity), boric acid (pH buffer), sodium dodecyl sulfate (surfactant), saccharin (a brightening agent) and in the case of composite coatings, an aqueous suspension of graphene oxide flakes. The Watts bath has been used because it is characterized by high efficiency and stable work [19][20]. Saccharin, as an additive to the bath, influences the fragmentation of the structure of the coatings [21].…”