Development of hydroxyapatite coating on porous titanium via electro-deposition technique

摘要

Titanium disks were fabricated with a porous surface layer and a dense inner core by utilizing microwave sintering. Hydroxyapatite (HA) was electro-deposited on the surface of the titanium. The electrolyte consisted of Ca(NO{sub}3){sub}2·4H{sub}20 and NH{sub}4H{sub}2PO{sub}4. This initial investigation examined the effect of current (0.2 and 0.4 Amperes) and duration (1, 5, 10 and 30 minutes) on coating morphology and phase evolution. The capability of electodeposition technique to infiltrate the pores of the titanium substrate was also considered. The interconnected surface pores allowed for infiltration of the HA coating as seen through scanning electron microscopy. Uniform coating of HA was best achieved with lower current values (0.2 Ampere) as it reduced the evolution of hydrogen gas during the coating. The application of pulsed current further improved the uniformity of the coating. Phase analysis of the coating, via X-ray Diffraction, revealed the presence of calcium hydroxide during the initial stages of the electro-deposition process.