Advanced Alloys for Biomedical Implants College of Engineering & Applied Science Materials Science and Engineering Department Advanced Alloys for Biomedical Implants by Murtatha Jamel

Why Mg Physical Properties Compatibility The density (1.7-1.85 g/cm3) is similar to human cortical bone (1.75 g/cm3) Mechanical properties, E of natural bone (10–20 GPa), Mg (41–45 GPa) Can reduce stress shielding effect Compatibility Mg has no toxic effect Can be absorbed by the body as vitamins Intake of Mg 240–420 mg/day The excess will be excreted by the kidneys and intestine Stimulates multiple enzyme system 1.Chen (2014), 9. Li (2013)

Biodegradable-Nontoxic Mg-Alloying System Objectives & Novelty Selecting alloying elements with good biocompatibility Eliminating the processing defects Reducing micro segregation by using rapid solidification. Studying the effect of cooling rate and alloying elements Studying the relationship between the grain size and alloy performance Studying the effectiveness of shifting the overall chemical potential of the alloy Novelty Biodegradable-Nontoxic Mg-Alloying System

Conclusion The grain size was reduced with increasing the cooling rate Increasing the content of alloying elements refined the structure and prompted more continuous secondary phase The rapid solidification improved the hardness by 40% Adding alloying elements further improved the hardness up to 65% The impact strength was slightly affected by the cooling rate and alloying elements The fracture morphology showed slightly less deformation with increasing the cooling rate The deformation and fracture path were significantly reduced with adding alloying elements

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