FLAME SPRAY DEPOSITION OF COMPOSITE TITANIUM ALLOY AND BIOACTIVE GLASS COATINGS

Titanium alloy (Ti-6Al-4V) powder and bioactive glass (45S5) were deposited by flame spraying to fabricate coatings applicable for bone fixation implants. 15wt. % bioactive glass was blended with titanium alloy powder. The blended powder was deposited with a flame spray torch; pure titanium alloy was also flame-sprayed as a control. The as-deposited coatings were characterized with cross-sectional optical microscopy and scanning electron microscopy (SEM). Immersion testing in simulated body fluid (SBF) was carried out for 0, 1, 7, and 14 days. The in vitro bioactive response was assessed by determining if hydroxyapatite (HA) was present through SEM with energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). Optical analysis showed that the coatings had a rough and porous structure. The SEM, FTIR, XRD analyses showed the formation of some HA on the bioactive glass-alloy blend after 7 days of immersion. No HA was observed after 14 days on the pure titanium alloy coating control. The HA formation on the bioactive glass-alloy composite coating suggests that the addition of bioactive glass to the blend greatly increased the bioactivity of the coating through surface mineralization.