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Magnesium based alloys gained great interest for medical biodegradable applications. Limitations arise from high corrosion rates and mechanical properties of the Mg based alloys. In recent work it was shown that the corrosion rate of a precipitate free Mg-6Ag thin film can be reduced by a factor of three compared to pure sputtered Mg. As Mg-6Ag combines the very promising corrosion results with a potential therapeutically use of Ag ions, the investigation of their mechanical properties is needed for a full characterization of Mg-Ag alloys as biodegradable material. In this work the Ag content was varied from 2 to 10 wt%. The investigated thin film samples were dog-bone shaped samples with a thickness of 20 µm. The samples were fabricated by a combination of UV lithography, sacrificial layer technique and magnetron sputtering. The mechanical properties were determined using uniaxial tensile test. Compared to pure Mg samples fabricated by the same processing route the yield strength is approximately doubled for Ag containing samples. For films with a Ag concentration up to 8 wt% the elongation at fracture reaches a value of ∼7%. Further increase of the Ag concentration leads to lower elongation at fracture. Thus, especially due to the low corrosion rate, Mg-6Ag shows the optimum of all investigated alloys, with a yield strength of ∼310 MPa and an elongation at fracture of ∼6%.

FeMn alloys show a great potential for the use as a biodegradable material for medical vascular implants. To optimize the material properties, with respect to the intended application, new fabrication methods also have to be investigated. In this work different Fe–FeMn32 multilayer films were deposited by magnetron sputtering. The deposition was done on a substrate structured by UV lithography. This technique allows the fabrication of in-situ structured foils. In order to investigate the influence of the Mn content on the material properties foils with an overall Mn content of 5, 10, 15, and 17 wt % were fabricated. The freestanding foils were annealed post-deposition, in order to homogenize them and adjust the material properties. The material was characterized in terms of microstructure, corrosion, mechanical, and magnetic properties using X-ray diffraction, electron microscopy, electrochemical polarization, immersion tests, uniaxial tensile tests, and vibrating sample magnetometry. Due to the unique microstructure that can be achieved by the fabrication via magnetron sputtering, the annealed foils showed a high mechanical yield strength (686–926 MPa) and tensile strength (712–1147 MPa). Owing the stabilization of the non-ferromagnetic ε- and γ-phase, it was shown that even Mn concentrations of 15–17 wt % are sufficient to distinctly enhance the magnetic resonance imaging (MRI) compatibility of FeMn alloys.