Effect of processing conditions on the structural properties and corrosion behavior of TiO2-SiO2 multilayer coatings derived via the sol-gel method

TiO2-SiO2 multilayer protective coatings were prepared via the sol-gel method on a C45E steel substrate. The influences of the number of layers, annealing temperature and annealing atmosphere on the corrosion resistance were investigated. Electrochemical characterization showed correlations between the processing parameters and the corrosion resistance. A maximum polarization resistance of 61 k Omega cm(2) was achieved with coatings of three layers annealed at 900 degrees C in air compared to just 2 k Omega cm(2) for the uncoated C45E steel sample. This research revealed the possibility of preparing a dense corrosion-resistant layer on C45E steel with minimal surface defects by optimizing the processing parameters.