Effect of β-TCP on the In Vitro Biocompatibility, Mechanical Properties, and Corrosion Resistance of Centrifugally Cast Mg–2Zn–1Mn Alloy for Orthopedic Implants

Sports, trauma, inflammation, and age-related musculoskeletal diseases and abnormalities have increased the demand for orthopedic implant materials. In this context, this research work examines the potential of Mg–2Zn–1Mn alloy with xβTCP (x = 7.5, 10, and 12.5 Wt.%) composites as biodegradable materials suitable for temporary orthopedic implant applications. Despite its excellent biodegradable properties, magnesium degrades at a high rate in the body fluid environment. This rapid degradation could lead to the material breaking down before the fracture has fully healed. Hence this study explores the effect of incorporating bioactive ceramics β-tricalcium phosphate (β-TCP) into the Mg–2Zn–1Mn alloy to enhance its in-vitro biocompatibility, mechanical properties, and corrosion resistance. The β-TCP was added in varying compositions using the centrifugal casting process. The microstructural analysis was conducted using field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX), and X-ray diffraction (XRD) to ensure elemental composition and phase analysis. Mechanical testing, wear studies, electrochemical corrosion testing, and immersion studies were performed to evaluate the effect of β-TCP on the properties of the composites. Furthermore, the biological behavior was also assessed using the L-929 fibroblast cell line, and hemolysis tests were conducted to determine the hemolysis rate of the β-TCP reinforced magnesium composites. The findings reveal that the Mg–2Zn–1Mn-10βTCP composite shows a substantial decrease in corrosion rate (94.25%) compared to the Mg–2Zn–1Mn alloy in simulated body fluid conditions. These results indicate that β-TCP reinforcement in magnesium alloys can effectively regulate degradation rates, enhancing their suitability for temporary orthopedic implant applications.