Direct-ink writing of strong and biocompatible titanium scaffolds with bimodal interconnected porosity

International audience ; Additive manufacturing of porous Ti6Al4V (Ti64) parts is promising for biomedical applications. In this study, Ti64 scaffolds with two scales of interconnected porosity networks were developed using a direct-ink writing process. Inks were made by dissolving a copolymer (Pluronic F-127) in water to obtain a hydrogel, which was then loaded with Ti64 particles. Both Pluronic F-127 amount in the hydrogel and solid loading influenced ink printability, as shown by rheological measurements and printing accuracy investigation. The best compromise was obtained for a 25 wt% Pluronic hydrogel loaded with 50 vol% of Ti64 particles. A partial sintering of 2 h at 1200 ∘ C led to interconnected micropores within strut, which was characterised by X-Ray computed tomography. Sintered scaffolds presented a compressive strength higher than bone, with a similar Young's modulus. According to their biocompatibility, final microstructure and mechanical properties, these scaffolds show a promising potential for load-bearing implants.