Speaker
Description
Biodegradable implants constitute a new generation of biomedical materials that are being developed to assist the tissue healing processes and gradually corrode and degrade in-vivo after their function is being fulfilled. Among others, Fe-based alloys show promising mechanical properties such as ductility and high ultimate strength. However, the corrosion rate of those implants is relatively slow, therefore alloying with other elements such as Mn, is studied to accelerate the biodegradation rate.
In this work, porous Fe-Mn austenitic equiatomic alloy with additions of antibacterial elements such as Zn and Ag has been fabricated through powder metallurgy using two approaches, namely simple pressing of ball-milled powders and vacuum sintering at 1173K and polymeric sponge impregnation with slurry, followed by heat treating the foam/slurry mixtures at 1273K under a flow of Ar+H2. Antibacterial Zn and Ag, aimed at limiting the infection rates of implants, are added to the Fe50Mn50 base alloy using different approaches such as mechanical alloying of metallic powders or incorporation as nanoparticles through electrodeposition. As a result, materials with varying degrees of porosity and Zn/Ag distribution are obtained to assess their influence on the degradation rates. The microstructure of fabricated materials is studied using scanning electron microscopy and X-ray diffraction. Mechanical properties are examined through nanoindentation while biodegradability is investigated by immersing the specimens in simulated body fluid (Hank’s solution).
Our results reveal that porous, non-cytotoxic, metallic FeMn-based biomaterials with higher degradation rates can be fabricated by the powder metallurgy route. The addition of Zn/Ag is believed not only to accelerate the corrosion rate but also to limit the biofilm formation on the surface of implants.
| Speaker Country | Spain |
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