In this work, bimetallic Fe-Cu nanopowders with the addition of hydroxyapatite (HAp) were used for the fabrication of composite biodegradable material suitable for extrusion additive manufacturing processes. Varying the metal and organic binder constituents in the feedstock has led to high performance composite material. Increasing the organic binder content in the initial feedstock from 50 to 60 wt% contributes to the reduction of porosity of the obtained composites from 20.6 % to 8.9 %. The 45Fe-Cu-HAp samples were characterized by the highest mechanical properties in the tensile test: yield strength σ0.2 being 110 MPa and tensile strength σB being 150 MPa. The Young's modulus of all composites is close to that of the cortical bone tissue modulus (≈ 15 GPa). The microhardness of the composite has been shown to exceed that of pure iron more than in 2 times. Corrosion tests have demonstrated that the composite material with minimal content of the organic binder (50Fe-Cu-HAp) showed the highest corrosion rate, which makes it more attractive for its application in the fabrication of a biodegradable implant. From the findings, the presented composite material showed significant antibacterial activity (more than 99 % reduction) against S. aureus. The composites showed excellent biocompatibility against sensitive fibroblast cell line 3T3. The more than 90 % cell viability was observed after 24 hours incubated with sample.
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