Calcium Phosphate Glass Coating on Titanium Alloy by CO2 Laser Irradiation

A novel method of preparing a calcium phosphate glass coating on a metallic titanium alloy, Ti-29Nb-13Ta-4.6Zr (TNTZ), was developed by CO2 laser irradiation. It was difficult to melt 60CaO-30P2O5-3TiO2-7Na2O (mol%) glass powders dip-coated on TNTZ for joining by the irradiation of 5 W power. After a trace amount of sodium phosphate was dispersed between the glass particles on TNTZ, the CO2 laser was irradiated to the surface; sodium phosphate was melted by the irradiation to react with the surfaces of the glass particles and with the thin oxide layer on TNTZ, resulting in the formation of a strong calcium phosphate glass coating on the substrate.