Biodegradable iron–hydroxyapatite scaffolds fabricated via advanced rapid tooling: unveiling mechanical properties, corrosion behaviour, and biocompatibility

Abstract

Iron and hydroxyapatite (Fe–HA) bio-composites are promising for biomedical applications, yet their optimal composition for corrosion rate, mechanical properties, and biocompatibility remains unidentified. This study introduces an advancement in the rapid tooling process combining polymer 3D printing with loose powder sintering to fabricate Fe–HA scaffolds. A thorough investigation is carried out to evaluate the effect of varying hydroxyapatite (HA) compositions (5 to 15 wt.%) on the mechanical properties, in vitro degradation, and biocompatibility of Fe–HA composites for orthopaedic applications. Microstructural studies, elemental analyses, and phase determination using SEM, EDS, and XRD revealed a compact morphology with higher concentrations of Ca, O, and P in the 10HA-Fe samples, which also exhibited superior compressive strength and corrosion resistance. Notably, all HA-xFe (x = 5,10 and 15 wt.%) samples demonstrated promising biocompatibility without any sign of toxicity. However, 10HA-Fe claimed itself to be an optimal composition exhibiting balanced mechanical properties, microstructural stability, corrosion resistance, and biocompatibility. In the context of biomedical applications, these findings are crucial for advancing the quality of Fe–HA bio-composites. © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2025.