Development of Fe-Mn-Zn alloys via spark plasma sintering as biodegradable biomaterials: Corrosion behavior, mechanical properties, and antibacterial performance

Biodegradable metallic materials have garnered considerable interest in biomedical applications due to their capacity to degrade within the body, hence eliminating the necessity for surgical removal. This research focuses on the combination of mechanical alloying and spark plasma sintering (SPS) as a novel approach to develop Fe-Mn-Zn biodegradable alloys with the aim of modifying the degradation rate of Fe-based alloys. Two alloy compositions, Fe-30Mn and Fe-30Mn-5Zn (wt%), were produced and evaluated for their microstructural, mechanical, electrochemical, and antibacterial characteristics. The addition of Zn led to a refined microstructure with reduced pore size due to liquid-phase sintering. Consistent with the electrochemical impedance spectroscopy (EIS) results, potentiodynamic polarization evaluation indicated a higher corrosion rate in Fe-30Mn-5Zn (3.64 × 10 -6 A/cm 2 ) compared to Fe-30Mn (3.11 × 10 -6 A/cm 2 ). The mechanical investigation demonstrated improved compressive strength (2023 MPa) and microhardness (305 HV) in the sample containing Zn. Furthermore, antibacterial evaluations revealed enhanced bactericidal efficacy of Fe-30Mn-5Zn against E. coli and S. aureus. The findings suggest that Fe-Mn-Zn alloys can provide significant mechanical strength, controlled biodegradability, and antibacterial properties, rendering them appropriate choices for biodegradable biomaterials applications.