Investigating the Synergistic Impact of TiB<sub>2</sub> and ZrO<sub>2</sub> Reinforcements on Forged AA7075-Based Hybrid Metal Matrix Composites

In today's automotive, aerospace, and high-temperature applications, there is a pressing demand for lightweight, high-strength materials. Meeting these industry requirements necessitates the development of such materials through rigorous research efforts. This study is focused on synthesizing, characterizing, and exploring the mechanical and tribological properties of forged AA7075-based Hybrid Metal Matrix Composites (HMMCs) reinforced with TiB 2 (titanium boride) and ZrO 2 (zirconium oxide) particles. The composites were subjected to hot forging, and comprehensive analyses were conducted to assess their microstructural features, elemental composition, and phase distribution. Mechanical properties were evaluated to gauge the enhancements achieved by incorporating TiB 2 and ZrO 2 reinforcements. Tribological behavior was examined using a tribotester under diverse conditions to elucidate the influence of these particles on wear resistance and frictional characteristics, thereby shedding light on potential applications in demanding tribological environments. This investigation incorporates varying percentages of ZrO 2 (zirconium dioxide) by weight (4% and 6%) and TiB 2 particles at 5% by weight into an AA7075 matrix alloy to synthesize a composite material. Scanning Electron Microscope (SEM) micrographs illustrate the uniform distribution of ZrO 2 and TiB 2 particles achievable through the stir casting and grain refinement after the forging process. Experimental results demonstrate that the addition of ZrO 2 and TiB 2 particles enhances the hardness and tensile strength of the AA7075/ZrO 2 /TiB 2 composite compared to the base matrix material, with the AA7075/5%TiB 2 /4%ZrO 2 composite exhibiting the highest hardness and strength among all variants. At the same time, tribological evaluations underscored enhanced wear resistance and frictional performance, indicating suitability for applications where tribological stability and mechanical strength are paramount. This investigation contributes valuable insights to developing advanced MMCs for high-performance engineering applications, demonstrating that the forging technique facilitates fine grain refinement, enhancing the abovementioned properties. Furthermore, the study identifies notable property improvements achieved through the forging process.