Compressive Behavior of Hybrid Solid-Lattice Structures Produced via EB-PBF Process Using Ti6Al4V Alloy

Metallic lattice structures can be extremely useful in prosthesis development since their use allows the tuning of density and elastic modulus of the components. The latter effect is fundamental to control and avoid the so-called stress shielding effect, which is responsible for a progressive weakening of the bone tissue. This is typical for instance for hip endoprosthesis. In addition, the topology of lattice structures encourages bone tissue ingrowth into the prosthesis, representing a further advantage in terms of osteointegration of these biomedical devices. Additive Manufacturing represents the most suitable technology to manufacture prosthesis containing lattice structures since it allows a great freedom of design, which is hardly possible with conventional technologies. The design and characterization of these complex structures is crucial to develop reliable prosthesis, especially if the extreme variety of geometrical topologies is considered. Furthermore, lattice structures are frequently integrated into bulk structures or are connected to a bulk structure. In this case, also the interaction between the two parts has to be taken into account since the interface can represent a weak point when the component is loaded. In the present contribution, the microstructural and mechanical characterization of lattice structures produced with powder bed fusion technology using Ti6Al4V alloy is discussed. In detail, cylindrical lattice samples consisting of a solid external shell and an inner lattice part were manufactured and tested and the obtained results allowed a further understanding of the mechanical performance of these structures.