Electrochemical and biomimetic deposition of calcium phosphates on titanium alloys

The presence of impurities of other metals in titanium alloys affects the composition of the oxide film after heat treatment: in addition to rutile, the VT 00 alloy contains Ti6O oxide, which in the VT 1-0 and VT 6 alloys is transformed into Ti3O oxide, which affects the corrosion resistance and mechanical strength. Calcium phosphate coatings containing brushite, calcite and apatite were obtained by electrochemical deposition on titanium plates at room temperature, pH 5, and a constant current density of 30 mA/cm2 from a suspension electrolyte CaCO3 / Ca(H2PO4)2. A layer of amorphized apatite was applied to the coatings using the biomimetic method in a 3-fold concentrated model solution of Simulated Body Fluid to improve biocompatibility. After heat treatment at 800°C, calcium phosphate coatings obtained on titanium VT 00 have greater biocompatibility, but lower resorbability, due to the presence of a larger amount of crystalline hydroxyapatite in the coating.