Study of Ni-TiO2 nanocomposite coating prepared by electrochemical deposition

Advances in materials performance often require the development of composite system. Nanocomposites containing titanium oxide nanoparticles in a nickel matrix have been prepared by means of electrocodeposition process from nickel plating bath an sulphate bath. The nanocomposite coatings were obtained by codeposition of the TiO2 nanoparticles (mean diameter 21 nm) with nickel during plating process. The surface morphology and microstructure of the nickel matrix was significantly altered due to the presence of titania nanoparticles. In the case of both nickel baths, the Vickers microhardness showed a tendency to increase with the amount of particle incorporation. The corrosion behaviour of the electrodeposited nickel in 0.5M Na2SO4 and 0.5M NaCl was studied using electrochemical methods. The corrosion rate calculated by polarization potentiodynamic curves obtained after 30 min and 1 h from immersion in solution is bigger for nanostructured coatings in 0.5M Na2SO4 (5.92 μm/year) and a little bit smaller in 0.5M NaCl (3.77 μm/year).