Heightened concerns over the exhaustion of natural mineral resources, escalating waste accumulation, and the need for lightweight materials to meet strict emission norms have spurred growing interest in sustainable aluminium-based composites. In this work, a hybrid aluminum matrix composite was developed using Al6063 as the base material and agricultural waste-derived eggshell powder (ESP) and rice husk ash (RHA) as reinforcing phases. The composites were manufactured via stir casting by varying the RHA content between 1 and 5 wt% and the ESP content between 2 and 10 wt%. The addition of ESP and RHA decreased material density while simultaneously enhancing mechanical and tribological characteristics. Compared with unreinforced Al6063, Rockwell hardness improvements of 12%, 16%, 20%, 32%, and 24% were observed, with the highest increase of 32% for the S2 composite. Compression strength showed remarkable enhancement, exhibiting increases of 409.22%, 663.8%, 361.48%, 90.96%, and 154.61% relative to the base alloy. Microstructural investigations revealed uniform dispersion of the reinforcement particles throughout the aluminum matrix, and fractographic analysis indicated a predominantly brittle fracture mechanism. The results demonstrate the potential of using low-cost agricultural waste materials to produce lightweight, cost-effective, and environmentally sustainable aluminium matrix composites suitable for advanced engineering applications.
Hatti et al. (Sun,) studied this question.