Materials used for biomedical applications, such as permanent or bioresorbable implants, require adapted mechanical properties as well as biocompatible features. Titanium alloys are coated with a passivating titanium oxide layer and therefore, have a high corrosion resistance along with an excellent biocompatibility and adequate mechanical properties. TiAl6V4 alloys are already established in biomedical engineering. Due to the addition of niobium and, in consequence, the impact on the hexagonal close packed (hcp) α- und body-centred cubic (bcc) β-phase, the performance of such an alloy can be enhanced, so that the requirements for biomedical applications can be achieved.
In this context, additive manufacturing is feasible for the production of individualized, patient specific implants made from TiAl6Nb7. In order to process TiAl6Nb7 by means of powder-bed-based, selective laser melting the processability has to be reproducible and ensured. The process parameters, e.g. laser power, scan strategy, scan speed and hatch distance, are varied and adjusted so that the required mechanical properties, based on the microstructure, can be achieved. In addition, analysis of the microstructure via light microscopy (LM) as well as via scanning electron and transmission electron microscopy (SEM, TEM) are employed and the mechanical properties are assessed by tensile tests. In further studies the long term stability (LCF and HCF) and the corrosion resistance in body-like media (m-SBF) will be determined.
The aim of the DFG funded project of the Chair of Materials Science (Paderborn University, Germany), the Chair of Materials Technology (Technical University of Dortmund, Germany) and the University of Veterinary Medicine Hannover, Foundation (Hannover, Germany) is the transfer of knowledge to the application of multi-layered or graded coating systems of Ti(Zr,Hf)CN coated implants.