Fabrication and characterization of Mg-Zn alloys reinforced with carbon nanofiber for orthopaedics implant application: A study on the different compositions

Abstract

Introduction: Biodegradable materials, such as Mg-based, Fe-based, and Zn-based, bring as much attention as bone-implant materials due to its biocompatibility and biodegradability characteristics. Among them, the Mg is the most abundant elements in human body and primarily found in the bones. However, the Mg has a lower mechanical properties and resistances to fracture compared to the other biodegradable and non-biodegradable metals. Therefore, the aim of this study was to develop a possible biodegradable material made of Mg-Zn alloys reinforced with carbon nano fiber (CNF) and later tested with several testing procedures. Methods: The powder metallurgy method (PM) was utilized to fabricate a total of 24 samples of Mg-Zn alloys reinforced with 1.0%wt, 1.2%wt, 1.4%wt, 1.6%wt, 1.8%wt and 2.0%wt of CNF. The PM method was involved with the process of grinding using ball milling, compaction under 400MPa pressure and sintered under 400 °C. Compression testing was done to measure the mechanical strength meanwhile scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDS) was used to identify the microstructural of samples. Results: From this study, it was found that Mg-Zn alloys with 1.6 wt% of CNF produce the highest Young's modulus (2687.91MPa) with acceptable yield strength (84.91MPa). For microstructural analysis, the results showed a compact surface for 1.2, 1.4 and 1.6 wt% of CNF and non-homogeneous structure of all the samples. Conclusion: In conclusion, this study has successfully shown the promising use of Mg-Zn-CNF composite as new materials for implant in terms of suitable strength and structure.