Corrosion Performance of Ni-TiO2 Nanocomposite Coatings in NaCl, HNO3 and NaOH Solutions

Ni-matrix nanocomposite coatings with various contents of TiO₂ nanoparticles were prepared by electrodeposition in a Ni plating bath containing TiO₂ nanoparticles to be codeposited. The surface morphology of coatings was studied by scanning electron microscopy (SEM). The codeposited TiO₂ nanoparticles were uniformly distributed in the Ni matrix. The corrosion performance of coatings in the 0.5M NaCl, 1M NaOH and 1M HNO₃ as corrosive solutions was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy methods. With increasing of TiO₂ nanoparticles content in the coating, the polarization resistance increases, the corrosion current decreases and the corrosion potential shifts to more positive values.