Last modified: 2018-07-24
Abstract
The aim of this work was to produce and to characterize composite deposits of nickel titanium dioxide on copper substrate. These deposits are obtained from watts bath without additives [1]. Titanium dioxide is one of the most important oxides used in the engineering materials. The oxide is used in electrochemical deposition of a substrate within sufficient properties.
Ni and Ni–TiO2 films were galvanostatically deposited on copper substrate from nickel sulfate bath. The composite coatings of nickel incorpating TiO2 nanoparticules were characterized by using electrochemical methodes such as open circuit potential (ocp) measurements, polarization curves and electrochemical impedances spectroscopy, the corrosion behavior of the nickel-TiO2 coating was examined. The corrosion tests in an agressive 3.5% NaCl solution indicate a reduced electrochemical activity and a high corrosion resistance in the case of composite deposits compared to the deposition of pure Ni, being confirmed the beneficial effect of the incorporation of TiO2 into the Ni matrix. The best results are obtained for a concentration of 5 g / l of TiO2.The results of the impedances are in agreement with the results of the currents of corrosion and the resistance of polarization which indicate the best resistance to corrosion in the case of the deposition of Ni obtained from the bath in the presence of 5 g / l TiO2
Keys word : Corrosion, electrolytic codeposition, nickel composite
References
[1] D. Peltcher, "˜Industrial Electrochemistry, Chapman & Hall, New York, (1984) , p. 184.