MECHANICAL TESTING AND NUMERICAL MODELLING OF POROUS STRUCTURES IMPROVING OSEINTEGRATION OF IMPLANTS

Implants, such as dental, are ordinary devices in medical care nowadays, even though they are quite expensive. In the present study, the use of trabecular and gyroid structures as external layer of implants is examined. The advantage of porous structures compared to surface modification of compact implants is the possibility to be fabricated by additive manufacturing together with the whole implant. The additive manufacturing also allows us to produce various shapes with controlled porosity for bone ingrowth. The design of 6 types of trabecular and 4 types of gyroid structures is part of the study. The trabecular structures are strut-based, whereas the gyroid structures are based on a wall system. The study is focused on mechanical testing of samples which were 3D printed from the titanium alloy Ti6Al4V. The gyroid structures, which we evaluated as more reliable, were chosen for numerical modelling. Other observed advantages and disadvantages of the structures are also discussed

GEOMETRY AND MECHANICAL PROPERTIES OF A 3D-PRINTED TITANIUM MICROSTRUCTURE

Construction applications sometimes require use of a material other than construction steel or concrete – mainly in cases, where strength to weight ratio needs to be considered. A suitable solution to this problem are structures manufactured using the 3D printing process, as they have a very good strength to weight ratio (i.e.: Ti-6Al-4V – σult = 900 MPa and ρ = 4500 kg/m3). Trabecular structures are porous structures with local material characteristics identical to their commonly manufactured counterparts, but due to their geometry, they have different global mechanical properties and are suited for special applications. We designed and manufactured six variants of these structures and subjected them to uniaxial compression tests, nanoindentation tests and subsequently evaluated their differences and elastic moduli. The values of global moduli E are in the range of 2.55 GPa – 3.55 GPa for all specimens