Microstructure and Corrosion Resistance of Composite nc-TiO2/Ni Coating on 316L Steel

Abstract

The aim of this work was to obtain composite of nc-TiO2/Ni coatings on 316L steel and to characterize their corrosion resistance. In order to investigate the influence of the addition of TiO2 nanoparticles, both pure Ni and composite nc-TiO2/Ni coatings were electrodeposited from nickel citrate baths. The microstructure of the coatings was examined by scanning and transmission electron microscopy. The nc-TiO2/Ni coatings were about 10 μm thick. Their microstructure consisted of TiO2 nanoparticles uniformly distributed in nanocrystalline Ni matrix. The corrosion resistance of the coatings was measured using impedance spectroscopy and polarization curves techniques in Ringer’s solution. It was determined that the addition of nano-TiO2 particles improved corrosion resistance and reduced corrosion rate of the coated steel.

Keywords

• nc-TiO2/Ni coatings
• electrodeposition
• nanocomposite
• microstructure
• corrosion resistance