Design and manufacturing of graded high-purity magnesium-calcium-zinc-material by fractional crystallization for the application as biodegradable implant material

• Applicants: Professor Dr.-Ing. Bernd Friedrich; Professorin Dr.-Ing. Daniela Zander
• Subject Area: Metallurgical, Thermal and Thermomechanical Treatment of Materials ; Biomaterials
• Term: from 2019 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 431892627

The objective of this research project is to develop an innovativealternative manufacturing process to vacuum distillation in order tomanufacture high-purity magnesium for implementation asbiodegradable implant material. As this proposed method is based on fractional crystallization, this production method of high-purity magnesium and magnesium alloys will reduce equipment Investments while simultaneously increasing production speed and resource efficiency. Utilizing the “striation” phenomena, alloying elements (e.g. calcium and zinc) will be integrated into the substrate material with increasing concentrations over the cross-section, but within one processing step and without the currently required re-melting step. With the production of graded magnesium materials, the currently unattainable degradation design defined in the literature as optimally initiating slowly before increasing degradation rate, can be realized. Investigations regarding the degradation processes will confirm the suitability of fractional crystallization with regards to the manufacturing aspects in addition to the targeted degradation design while simultaneously characterizing the corrosion mechanisms which occur in graded materials. In order to accomplish this, high-purity magnesium is required as impurities are known to cause synergistic effects with both the microstructure and corrosion processes. Through this project, an essential, fundamentally-based contribution to the manufacturing and development of implantable magnesium can be achieved.

• DFG Programme: Research Grants