Silane-Based Coatings Containing TiO2 for Corrosion Protection of 316L Stainless Steel

The present work aims to evaluate the electrochemical behaviour of 316L stainless steel flat sheets both uncoated and coated with an organic–inorganic silane hybrid formulation based on TEOS (tetraethyl orthosilicate) and TMES (Trimethylethoxysilane) as silane precursors. The influence of the modification of the silane-based layer by the incorporation of 3-aminopropyl trimethoxysilane (APS) doped TiO2 (N-TiO2) on the pitting properties of the coatings has been studied. The obtained protective films have been characterized from compositional (EDX), morphological (FE-SEM), and electrochemical (corrosion) points of view. Concerning their morphology, the coatings look continuous and smooth. Regarding their electrochemical properties, the results show that the application of the developed N-TiO2-containing silane coatings extends the passive potential range of 316L stainless steel in simulated body fluid; thus, it improves the pitting resistance of the substrate.