Development of biodegradable Fe-Mn thin structures by electroforming in deep eutectic solvents

Fe-Mn alloys represent promising candidates for temporary biomedical intravascular implants with a thin structure (e.g., coronary, cerebral and peripheral stents) due to their high mechanical strength, acceptable biocompatibility, and controllable corrosion rate. Traditionally, these devices are produced by casting followed by thermo-mechanical processing, i.e. a time- and energy-intensive top-to-bottom approach. This study explores electroforming as an alternative method to fabricate bottom-to-top thin Fe-Mn structures using ethylene glycol-based deep eutectic solvents (DESs). Glycine was introduced as a complexing agent to enhance Mn co-deposition. Electroforming was investigated in presence of three glycine concentrations (0.2, 0.4, and 0.6 M), and the the microstructure, composition, corrosion behavior, and cytocompatibility of the developed thin (50-85 µm) structures were characterized. Higher glycine content improved Mn incorporation, crystallinity, hardness and increased corrosion rate. These findings support the use of DES-based electroforming as a promising route for fabricating biodegradable Fe-Mn devices with tunable properties.