Biodegradable Fe-based alloys have emerged as potential candidates for temporary orthopedic implants due to their favorable mechanical performance and their higher degradation rate compared to pure iron. However, their fabrication by laser powder bed fusion (LPBF) typically employs pre-alloyed spherical powders produced by gas atomization, which increases the cost of manufacture. In this work, a robust, versatile, and affordable powder preparation route is proposed for the LPBF fabrication of biodegradable austenitic FeMnC alloys using irregular elemental particles. The approach starts from mechanical mixing of Fe, Mn, and C powders followed by a thermal treatment and milling to improve the flowability and promote elemental diffusion. Five conditions were evaluated to investigate how laser power and scanning velocity influence the properties of the printed samples, such as microstructure, porosity, hardness and corrosion behavior. The printed Fe12Mn1.2C alloy exhibited a fully austenitic microstructure, with pore size and interconnection strongly dependent on the chosen values of laser power and scanning velocity. Microhardness values around 350 HV were obtained, which are higher than those typically reported for conventionally processed Hadfield-type steels. Electrochemical analyses demonstrated that samples with higher porosity exhibited an accelerated degradation rate (∼2 mmpy), governed mainly by charge-transfer processes and enhanced by diffusion-assisted pathways. Overall, this research demonstrates the viability of the proposed powder preparation method to use irregular elemental powders for LPBF processing and highlights the potential of this cost-effective route for the manufacture of biodegradable FeMnC alloys.
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