Additive manufacturing of biomimetic Titanium-Tantalum lattices for biomedical implant applications

Abstract

Although additively manufactured titanium-tantalum alloys can offer unique mechanical and biological advantages for implant applications, their use in conjunction with engineered lattice architectures is yet to be explored. In the present study, the promising gyroid, diamond and Schwarz primitive minimal surfaces are used for the design of 3D lattices for biomedical implants. The lattices are fabricated using laser powder-bed fusion and a blend of elemental titanium-tantalum powder. The processability, compressive mechanical properties and in vitro biological properties of the dense and lattice samples are assessed via non-destructive and destructive characterization methods. The topologies from the designed structures are retained through processing and the compressive tests results show that the strength-to-modulus ratios are comparable to the conventional Ti-6Al-4 V alloy. However, the higher ductility and absence of toxic elements make the Ti-25Ta lattices a more favourable option for a new generation of implants. Compared to conventional lattices, the designs presented here also show advantageous mechanical properties for use in bone implants with higher elastic admissible strains. The in vitro cell cultures confirm the high biocompatibility of the material and improved biological response of the interconnected lattices over dense material.

Keywords

• Laser powder-bed fusion
• Titanium
• Tantalum
• Biomedical implants
• Lattices