Exploring the Effects of Ball Milling and Microwave Sintering on Microstructural and Mechanical Behavior of AA7075/SiC/ZrO₂ Hybrid Composites

Particle reinforced metal matrix composites, owing to their superior performance compared to their parent alloys, are currently in high demand across industrial sectors. This study aimed to enhance the performance of the base alloy by fabricating an AA7075/SiC/ZrO₂ hybrid composite utilizing microwave energy. Ball milling was employed to effectively disperse the reinforcements within the matrix material. The incorporation of SiC reinforcement led to noticeable improvements in mechanical properties up to the critical weight fraction. However, significant enhancements in mechanical properties were observed upon introducing ZrO₂ into the matrix material. The composite achieved remarkable mechanical strength, with compression and hardness values reaching 345 MPa and 140 HV, respectively, when a composition of 7% SiC and 3% ZrO₂ was integrated into the AA7075 matrix. Furthermore, during attempts to disperse higher reinforcement content levels with extended ball milling durations, non-uniform strains were noted in the SiC particles, indicating lattice defects that may contribute to the generation of intermetallic compounds, even within the microwave sintering process. Composite processed at 8% SiC content levels with extended ball milling showed a decreased trend in its mechanical properties, noted a strength of 272 MPa in compression. This research highlights the potential for tailoring advanced composites with enhanced mechanical properties for various industrial applications.