resumo
Titanium and its alloys are widely used as materials for implants, owing to their corrosion resistance, mechanical properties and excellent biocompatibility. However, clinical experience has shown that they are susceptible to localised corrosion in the human body causing the release of metal ions into the tissues surrounding the implants. Several incidences of clinical failures of such devices have demanded the application of biocompatible and corrosion resistant coatings and surface modification of the alloys. Coating metallic implants with bioactive materials is necessary to establish good interfacial bonds between the metal substrate and the bone. Hence, this work aimed at developing a bioglass-apatite (BG-HAP) graded coating on Ti6Al4V titanium alloy through electrophoretic deposition (EPD) technique. The coatings were characterized for their properties such as structural, electrochemical and mechanical stability. The electrochemical corrosion parameters such as corrosion potential (E(corr)) (open circuit potential) and corrosion current density (I(corr)) evaluated in simulated body fluid (SBF) have shown significant shifts towards noble direction for the graded bioglass-apatite coated specimens in comparison with uncoated Ti6Al4V alloy. Electrochemical impedance spectroscopic investigations revealed higher polarisation resistance and lower capacitance values for the coated specimens, evidencing the stable nature of the formed coatings. The results obtained in the present work demonstrate the suitability of the electrophoretic technique for the preparation of graded coating on Ti6Al4V substrates. (C) 2008 Elsevier Ltd. All rights reserved.
palavras-chave
HYDROXYAPATITE COATINGS; STAINLESS-STEEL; IN-VITRO; IMPEDANCE SPECTROSCOPY; METALLIC BIOMATERIALS; TITANIUM-ALLOYS; CORROSION; GLASS; INTERFACE; IMPLANTS
categoria
Electrochemistry
autores
Balamurugan, A; Balossier, G; Michel, J; Ferreira, JMF
nossos autores
José Maria da Fonte Ferreira
Professor(a) Jubilado(a)agradecimentos
Financial support by the CICECO, University of Aveiro, Portugal and the technical support from INSERM ERM 0203, University of Reims, France are gratefully acknowledged. The authors also would