Study of the mechanical behavior and corrosion resistance of hydroxyapatite sol–gel thin coatings on 316 L stainless steel pre-coated with titania film

Autor: Sabeha Yala, Djahida Sidane, Didier Chicot, Hafit Khireddine, Alain Iost, S. Ziani, Xavier Decoopman
Přispěvatelé: Laboratoire de Mécanique de Lille - FRE 3723 (LML), Université de Lille, Sciences et Technologies-Centrale Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Génie Civil et Géo-Environnement (LGCgE) - ULR 4515 (LGCgE), Université d'Artois (UA)-Université de Lille-Ecole nationale supérieure Mines-Télécom Lille Douai (IMT Lille Douai), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-JUNIA (JUNIA), Université catholique de Lille (UCL)-Université catholique de Lille (UCL), Université Abderrahmane Mira [Béjaïa], Université de Lille, Sciences et Technologies, Mechanics surfaces and materials processing (MSMP), Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM), Université de Lille, Sciences et Technologies-Ecole Centrale de Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)
Rok vydání: 2015
Předmět:
Zdroj: Thin Solid Films
Thin Solid Films, 2015, 593, pp.71-80. ⟨10.1016/j.tsf.2015.09.037⟩
Thin Solid Films, Elsevier, 2015, 593, pp.71-80. ⟨10.1016/j.tsf.2015.09.037⟩
ISSN: 0040-6090
Popis: International audience; In order to reinforce the clinical applications of hydroxyapatite (HAP) sol–gel coatings deposited onto 316 L stainless steel, we suggest the introduction of an intermediate thin layer of titania (TiO2) on the substrate. The titania sub-layer is introduced in order to improve both the corrosion resistance and the mechanical properties of the HAP/316 L stainless steel coated system. The two coatings, HAP and TiO2, were studied separately and afterwards, compared with the bi-layered coating. A film without any cracks is obtained under the optimum conditions in terms of annealing temperature, dipping rate and aging effect. Microstructural, morphological and profilometry analysis revealed the non-stoichiometric carbonated porous nature of the hydroxyapatite coatings, which were obtained after annealing at 500 °C during 60 min in the atmosphere. The obtained TiO2 coatings exhibit a dense and uniform surface. Addition of TiO2 as sub-layer of the HAP coating tends to increase the homogeneity and the crystallinity rate as compared to the HAP one.The mechanical properties, i.e. hardness and elastic modulus, are determined by means of nanoindentation experiments and the adhesion between the coating and substrate is estimated by scratch tests. The corrosion behavior is evaluated by potentiodynamic cyclic voltammetry tests. As a main result, the values of the elastic modulus and hardness, respectively of 30 GPa and 2.5 GPa, are relatively high for the HAP–TiO2 bilayer coating. This result allows the use of such coated material as a replacement material for hard tissues. The adhesion strength increased from 2925 mN up to 6430 mN after the addition of the TiO2 intermediate film. According to the Tafel's analysis, the 316 L stainless steel specimens coated with both HAP and titania layers (ECorr = − 234 mV, lCorr = 0.089 μA cm− 2) present a better resistance than the HAP-coated specimens (ECorr = − 460 mV, lCorr = 0.860 μA cm− 2).
Databáze: OpenAIRE
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