Corrosion behaviour of composite coatings obtained by electrolytic codeposition of zinc with nanoparticles of Ce[O.sub.2] x Zr[O.sub.2] binary oxides

Composite Zn coatings incorporating Ce[O.sub.2] x Zr[O.sub.2] nanoparticles were obtained by electrodeposition on steel from an industrial electrolyte, containing 75 g [L.sup.-1] Zn[Cl.sub.2], 230 g [L.sup.-1] KCl, 20 g [L.sup.-1] [H.sub.3]B[O.sub.3] and two additives, 1 mL [L.sup.-1] each. The influence of the oxide nanoparticles on phase composition, morphology and structure of the obtained coatings was investigated by X-ray diffraction and SEM-EDX methods. By using polarization measurements, the corrosion behaviour of the deposits was examined and the corrosion process on Zn-Ce[O.sub.2] x Zr[O.sub.2] composite coatings was compared with that taking place on composite coatings prepared with a simple mixture of Ce[O.sub.2] and Zr[O.sub.2] oxides and with each oxide separately. On all the composite coatings, corrosion was found to be slower than on the pure Zn surface. Keywords: Corrosion; Electrodeposition; Zinc-nanoparticles composite coatings; Ce[O.sub.2] x Zr[O.sub.2] binary oxides