MagTi-Implant - Hybrid implants made of magnesium and titanium using L-PBF

• Applicant: Professor Dr.-Ing. Sebastian Härtel
• Subject Area: Primary Shaping and Reshaping Technology, Additive Manufacturing
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 534007237

Currently, the various materials approved in medical technology are combined in implantable joint replacements by means of different individual components. The combination of the materials magnesium and titanium within a hybrid implant leads to a significant improvement in the use properties, such as the ingrowth behavior and the longevity. However, a hybrid implant consisting of two different materials does not exist to date. The titanium-magnesium combination represents a great potential for application, whereby titanium can be used as a permanent base material in the combination. As a non-permanent material, magnesium alloys are coming into focus. These are ideally suited due to their similar strength properties to bone compared to other resorbable material alternatives and additionally due to the stimulation of bone growth, whereby during bone growth the magnesium part is dissolved in the human body and replaced by the new bone. In addition, the speed of the degradation behavior can be adjusted by a suitable choice of alloy. By combining the two materials, a permanent joint replacement can be implemented, with good accretion behavior due to the outer material. The global goal of the research project is to develop a basic understanding of how the conception (design) and process chain for manufacturing a hybrid implant (consisting of magnesium and titanium) must be designed in order to ensure safe behavior in the subsequent application. In the future, additive manufacturing will be used to create patient-specific implant solutions that will also be able to handle the subsequent loads. The aim of this project is to investigate the interactions between residual porosity and process parameters in the processing of magnesium materials using L-PBF. Such basic knowledge is essential for further investigations. On the one hand, high residual porosity tends to improve the ingrowth behavior of the implant, while on the other hand it reduces the mechanical load-bearing capacity. A further objective of the project is to investigate a methodology for the force-locked and material-locked joining of magnesium and titanium specimens produced by means of L-PBF in a subsequent HIP process. On the basis of simple geometries, a basic understanding is being created of how such a process chain must be designed in order to achieve both force and material closure.

• DFG Programme: Research Grants
• Co-Investigator: Dr.-Ing. Alexander Sviridov