Processing of HA-coated Ti–6Al–4V by a ceramic slurry approach: an in vitro study

Hydroxyapatite-coated titanium alloy composite powders (Ti–6Al–4V/HA) was produced by a ceramic slurry approach. The aim was to evaluate the stability of the coating when subjected to a physiological medium simulated body fluid (SBF). Three consolidation conditions (700°C for 5 h, 700°C for 8 h and 700°C for 11 h) were used in the production of the Ti–6Al–4V/HA composite powders. Results showed that biodissolution followed by apatite precipitation had taken place after soaking in SBF. In addition, it was found that consolidation at 700°C for 5 h resulted in a weak mechanical locking of calcium phosphate on the Ti–6Al–4V surfaces; and the formation of small crystallites, which would increase the dissolution rate.