Open AccessCHARACTERIZATION OF FLUORIDATED HYDROXYAPATITE (FHA) SOL-GEL COATINGS ON TITANIUM SUBSTRATE
Author(s) -
Ngo Thi Anh Tuyet
Publication year - 2018
Publication title -
vietnam journal of science and technology/science and technology
Language(s) - English
Resource type - Journals
eISSN - 2815-5874
pISSN - 2525-2518
DOI - 10.15625/2525-2518/55/5b/12208
Subject(s) - biocompatibility , titanium , materials science , scanning electron microscope , corrosion , simulated body fluid , nuclear chemistry , coating , sol gel , apatite , fluoride , substrate (aquarium) , metallurgy , chemical engineering , composite material , chemistry , mineralogy , inorganic chemistry , nanotechnology , oceanography , geology , engineering
In this paper, FHA coatings [FHA, Ca10(PO4)6(OH)2-x Fx] (wherein 0 ≤ x ≤ 2) were deposited on titanium substrate by sol-gel method with heat treatment at 900 oC for 4 hours. Different concentrations of F- were incorporated into the apatite structure during the sols preparation. The FHA sols were prepared using various amounts of ammonium fluoride [NH4F] with the [P]/[F] molar ratios of 12, 6, 4, 3 in order to have the corresponding compositions of Ca10(PO4)6(F0.5 OH1.5), Ca10(PO4)6 FOH, Ca10(PO4)6(F1.5 OH0.5) and Ca10(PO4)6F2, respectively. The fabricated FHA coatings were assessed by various methods, namely: morphological structure and chemical composition of coatings were studied by scanning electron microscopy (SEM) and Energy dispersive spectrometry (EDS). The anti-corrosion properties of samples were evaluated by Potentiodynamic polarization curves and Nyquist impedance spectrum. The biocompatibility of FHA coatings on titanium substrates were evaluated by in-vitro tests in simulated body fluid (SBF) solution during 21 days, and ICPMS (Inductively Coupled Plasma Mass Spectrometry) analysis method has been used. The results showed that with dense structure, FHA coatings expressed higher anti-corrosion and biocompatibility performance as compared with that of HA coating.