The aim of this work is the study of the interaction mechanisms between hydroxyapatite-zirconia interface and the zirconia layer (ZrO2) on a stainless steel substrate in the HA/ZrO2/316LSS system. The Hydroxyapatite (HA) layer was applied by the screen printing technique on ZrO2 film previously deposited by electrophoresis on 316LSS substrates. The bilayer system was thermally annealed at temperatures less than or equal to 700 °C for a maximum time of 5 minutes. The electro-deposited amorphous layers of zirconium hydroxide with a thickness about 8 µm showed good adherence to the stainless steel substrates and allowed good chemical anchorage with the HA layer after the thermal treatment, producing a thin layer of zirconia stabilized in tetragonal and monoclinic mixed phases. The thermal treatment also degraded HA layer to form calcium phosphates. The bilayer system of HA/ZrO2 on 316LSS substrate ensures a good anchorage, being a good and inexpensive candidate for a protective coating in stainless steel orthopedic prostheses. This solves the low adherence between HA and 316LSS, in addition of the low cost the 316LSS prostheses as a biocompatible system with low production costs.

Using the reactive magnetron rf co-sputtering technique and a Ti target partially covered with a small Al plate, TiAlN coatings were made on c-Si in a reactive atmosphere of nitrogen and argon. Coatings were deposited on substrates at 22°C and at 150°C. The substrate temperature notably affected the thickness, crystalline grain size, and hardness of the coatings. We analyzed the dependence of both structure and crystalline grain sizes on substrate temperature and the chemical composition of the coatings. The structural properties and the chemical composition were obtained by means of XRD and EDS techniques. High aluminum content was found in the coatings for the samples grown at the lower substrate temperature when samples were measured by electron dispersive spectroscopy technique. Atomic force microscopy measurements showed a surface morphology dependent on the nitrogen content. Scanning electron microscopy measurements showed a clear pyramidal microstructure of TiAlN coatings grown at 22°C, while the microstructure of those grown at a substrate temperature of 150°C were not well defined.