Biomimetic hydroxyapatite coatings deposited onto heat and alkali treated Ti6Al4V surface.

In the present work, time of calcium phosphate formation on Ti6Al4V alloy with or without alkali and heat treatments was investigated. Specimens were soaked in 0, 5 and 10M solutions of NaOH at temperatures of 60 and 80°C for 1 and 3 days and then their surfaces were characterised by using scanning electron microscopy and thin film X-ray diffraction. It was found that optimum condition is 3 days soaking in 5M NaOH in 80°C. Specimens treated under these optimum conditions were subsequently heat treated at 500, 600 and 700°C for 1 h to consolidate the sodium titanate hydrogel layer. With heat treatment at 600°C for 1 h and then soaking in simulated body fluid, apatite formed within 3 days. However, there were no signs of apatite formation in control samples (without alkali and heat treatment) up to 7 days soaking in SBF. [ABSTRACT FROM AUTHOR]