Experimental investigation on enhancing the mechanical properties of biodegradable Zn-3Mg alloys reinforced with snail-shell particulates via powder metallurgy

Biodegradable zinc-based alloys are promising candidates as a new generation implant materials due to their favorable degradation rates compared to magnesium and iron. However, their relatively low mechanical strength hinders their clinical usage. In this experimental study, Zn-3Mg/xSnS (x = 0.5-6 wt%) composites were manufactured via powder metallurgy. The performance of the obtained samples was systematically investigated via microstructural analysis (SEM), mechanical properties (compressive yield strength, elastic modulus, and hardness), in vitro degradation, and cytocompatibility with L929 fibroblast cells. According to the obtained results, SnS reinforcement significantly improved mechanical performance. Microstructural investigation revealed homogeneous SnS distribution and refinement of intermetallic phases. Among all the sample groups, Zn-3Mg-2SnS resulted in a compressive yield strength of 402 MPa, elastic modulus of 49 GPa, and hardness of 151 HV. Degradation tests were performed for 28 days, and the samples exhibited a moderate corrosion rate (similar to 0.2 mm/year). Cytotoxicity assays confirmed >70% cell viability at 50% extract concentrations. These results show that Zn-3Mg alloys can be efficiently reinforced with bio-derived SnS particles, improving their strength and biocompatibility without decreasing their degradation performance.