Effect of Deposition Parameters on Electrophoretically Deposited TiO2
In the current study, TiO2 coatings on stainless steel substrates were prepared by Electrophoretic Deposition (EPD) of colloidal dispersions of TiO2 nanoparticles in ethanol. The effects of deposition parameters on surface morphology, phase composition and mechanical properties were investigated. The surface morphology of the EPD layers was observed using Atomic Force Microscopy (AFM). The composition of the EPD layer was determined from the peak intensity using an X-ray Diffractometer (XRD) and mechanical properties of films were investigated by nanoindentation techniques. Characterization of the obtained films by atomic force microscope showed a relatively uniform microstructure. The coatings mainly consisted of anatase and rutile; anatase is the predominant phase with an average percentage of 71%. As a result of nanoindentation experiments, load–displacement curves were obtained and two mechanical characteristics of the substrate and investigated films – indentation hard-ness (HIT) and indentation modulus (EIT) – were calculated using Oliver & Pharr’s approximation methods. Mechanical properties show an improvement with the applied voltage. The results illustrate that Young's modulus and hardness of TiO2 thin films are increased with increasing voltage.
Dhiflaoui H, Khlifi K and Cheikh larbi AB