A New Process for the Thermal Treatment of Calcium Phosphate Coatings Electrodeposited on Ti6Al4V Substrate

This work presents a new experimental process for the thermal treatment of prosthetic coatings obtained by electrodeposition on titanium alloy Ti6Al4V. This thermal treatment is required to evaporate the solvent from the coating and to improve its cohesion and its adhesion to the titanium alloy substrate. When such treatment is carried out in air, the temperature is limited to 550 °C due to the high oxidation of the titanium substrate. To overcome this limitation, we introduce a new thermal treatment process using a controlled atmosphere obtained by Argon injection under vacuum. In these conditions, the temperature can be increased up to 1 000 °C. This process prevents the formation of the oxide layer onto the titanium alloy surface without noticeable modification of its mechanical properties. It also allows to obtain a fully crystallized biphasic coating made of hydroxyapatite and β‐tricalcium phosphate. Consequently, this work resulted in obtaining an implant (calcium phosphate coating on Ti6Al4V) with improved mechanical properties.