Preparación de recubrimientos de hidroxiapatita a partir de precursores de tipo sol-gel

Abstract

Since the 90s countless researches are carried out obtain a system that combines the mechanical advantages of the metals and the biological likeness of the hydroxyapatite ceramics. Hydroxyapatite coatings obtained via solgel have been used with these purposes. The preliminary results of an integrated study in which are observed diverse aspects as well as design, preparation, characterization and evaluation of the behavior against the corrosion of new hydroxyapatite coatings for biomedical applications are presented; on the superalloy of MA 956 titanium of nominal composition Fe-20 Cr-5 Al-0.5 Ti-0.5 Y₂O₃. A thermal treatment to produce a homogeneous and compact film a-aluminium oxide was previously applied over this superally, that acts as a barrier against the corrosion of the metallic substrate previously treated before the Hap coating. The hydroxyapatite layer deposited on the metallic substrate, was prepared using a variant of the process sol-gel used by D. M. Liu in alcoholic medium and later, crystallized by the novel technique of thermal treatment to controlled speed. The resulting hydroxyapatite coating was characterized by means of the reflection way of Fourier transform of infrared spectroscopy (FTIR), x-ray diffractions of closed angle (XRD), scanning electronic microscopy with micro- probe (SEM/DEX) and photo electronic of x-ray (XPS). The analyses of FTIR and XRD show the crystallinity of the phase and the homogeneity in the chemical composition of the formed hydroxyapatite, corroborated by the results obtained by XPS. The studies of SEM show the morphology of the coatings obtained.