Objectives: The goal of this work is to fabricate bioactive graded glass-ceramic coatings on Ti6Al4V by sequential dip coating. Methods: Cylindrical Ti6Al4V samples were coated using mixtures of glasses in the Si-Ca-Mg-Na-K-P-O system and calcium phosphates (hydroxyapatite, β-tricalcium phosphate, β-TCP, dicalcium phosphate anhydrous, DCPA). Two layers were applied by dip coating: a high-silica glass layer in contact with the metal and a glass-ceramic layer on the surface. In order to prepare the coatings, the samples were immersed in the appropriate suspensions in ethanol and were removed at controlled velocity. Subsequently, they were fired at temperatures ranging between 800 and 820°C for 0-30 s. Coating surfaces and polished cross sections were analyzed by XRD and SEM-EDS. The adhesion to the substrate was evaluated by interfacial Vickers indentation. The in vitro evolution of coatings in simulated body fluid (SBF) at 36.5°C was analyzed by XRD, FTIRSM and SEM-EDS. Results: It is possible to prepare dense coatings 50-100 µm thick by using suspensions with a solid content of 75 wt% and dipping velocities of 1 m/min. A two-way Anova and Tukey's tests showed that optimum glass-metal adhesion (as measured by indentation) was achieved by firing at 800-820°C for 5 s. Apatite precipitates covered 85±5% of the surface of those coatings containing a mixture of HA and a glass with 53 wt% SiO2 after one month in SBF. β-TCP and DCPA did not promote the in vitro precipitation of new apatite. Conclusion: It is possible to use sequential dipping to fabricate graded glass-ceramic coatings on Ti6Al4V that have optimum adhesion and can precipitate apatite during in vitro tests in SBF. This work was supported by the NIH/NIDCR Grant 1R01DE11289. Sonia Lopez-Esteban wishes to acknowledge Fulbright Grant and the Spanish Ministry of Education, Culture & Sports for financial sponsorship.

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