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Novel chitosan composite coatings containing titania nanoparticles (n-TiO 2 ) for biomedical applications were developed by electrophoretic deposition (EPD) from ethanol-water suspensions. The optimal ethanol-water ratio was studied in order to avoid bubble formation during the EPD process and to ensure homogeneous coatings. Different n-TiO 2 contents (0.5-10 g L 21) were studied for a fixed chitosan concentration (0.5 g L 21) and the properties of the electrophoretic coatings obtained were characterized.Coating composition was analyzed by thermogravimetric analysis (TG), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis. Scanning electron microscopy (SEM) was employed to study both the surface and the cross section morphology of the coatings, and the thicknesses (2-6 mm) of the obtained coatings were correlated with the initial ceramic content. Contact angle measurements, as a preliminary study to predict hypothetic protein attachment on the coatings, were performed for different samples and the influence of a second chitosan layer on top of the coatings was also tested. Finally, the electrochemical behavior of the coatings, evaluated by polarization curves in DMEM at 37 uC, was studied in order to assess the corrosion resistance provided by the n-TiO 2 /chitosan coatings.

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An intrinsic feature of the hot stamping process, in which a hot blank is quenched and formed between water cooled dies, is the severe thermo-mechanical deformation that the blank experiences under the combined influences of non-isothermal and non-proportional loadings. This results in challenges for conventional forming limit prediction models to accurately predict material behavior. In this paper, a novel viscoplastic-Hosford-MK model was developed to predict the forming limits of an Al-Li alloy under hot stamping conditions. The effectiveness of the developed model was verified by the demonstration of accurate responses to cold die quenching, strain rate and loading path changes, enabling the developed model to reveal a realistic critical material response under complex deformation conditions. Finally, by applying the developed model to the hot stamping of an AA2060 component, its accuracy was successfully validated. It was indicated that the onset of necking during hot stamping of the component did not necessarily occur at the maximum thinning region, and this was due to the comprehensive effects of varying loading path, strain rate and temperature. A detailed mathematical analysis of the developed M-K model was also conducted, and it was found that the incremental work per unit volume ratio (View the MathML source) between Zone b (where a thickness inhomogeneity exists) and Zone a (the remainder of the material) was a significant parameter that determined the formability of AA2060 under hot stamping conditions