Synergistic effect of niobium carbide and titanium nanoparticles on the mechanical and microstructural properties of Al-Zn-Mg-Cu alloy hybrid composites

In this study, an Al-Zn-Mg-Cu alloy matrix serves as the matrix material, with Niobium Carbide (NbC) and Titanium (Ti) nanoparticles acting as reinforcements to enhance composite strength. Incorporating nano-structured reinforcements significantly enhance both strength and toughness, surpassing micro-sized counterparts. To prevent nanoparticle agglomeration during manufacturing, we employ vigorous stirring via the stir casting technique to ensure uniform dispersion within the composite matrix. SEM analysis confirms uniform dispersion of NbC and Ti nanoparticles within the matrix. Experimentally, the composite exhibits exceptional tensile strength, with sample B achieving the highest load of 5500 N, correlated with an optimal NbC percentage of 5 wt% and Ti percentage of 2 wt%. However, increasing NbC percentage from 5 wt% to 10 wt% results in decreased ductility and tensile strength for composite C. Similar trends are observed in bending strength, with composite B exhibiting the highest load at 9023.8 N, surpassing samples C and D. Microhardness results demonstrate an increase with NbC content, peaking at 230 HV, but declining to 185 HV with reduced NbC and Ti concentrations. Charpy impact tests reveal a consistent rise in impact energy from samples B to D, attributed to the escalating proportion of NbC relative to Ti. Overall, meticulous material selection and processing optimization are essential for developing high-performance metal matrix composites with enhanced mechanical properties.