Influence of thermo-chemical treatment and particulate contents on mechanical and wear behavior of MangiferaIndica shell/calcium oxide hybridized epoxy-based composites

This study introduced a novel method for improving the mechanical and wear performances of epoxy-based composites using thermo-chemically treated Mangifera indica shell particulates (MIps) and calcium oxide (CaO) as hybrid reinforcement. Few studies on MIp-based composites did not examine the effects of advanced post-treatments on overall composite performance. In this study, MIps were refined to 45 µm and subjected to a two-step treatment: NaOH activation at 90 °C/4 h and HCl refluxing at 75 °C/2 h to improve interfacial bonding. The study assessed the synergistic effects of MIps and CaO on mechanical and wear performances via FTIR, SEM-EDS, mechanical testing, and density analysis. The results showed marked improvements with treated MIp: 155.6 % increase in tensile strength (299 MPa), 290.5 % increase in hardness (164 BHN), and 56.1 % reduction in wear rate (3.30 mm³/mm), compared to untreated MIp. CaO addition enhanced particle dispersion and carbide formation, with treated MIp composites achieving superior compactness and wettability. These findings highlight the potential of optimized MIp-CaO hybrids in sustainable composite development. The enhanced properties make them ideal for real-world applications in automotive components (e.g., dashboards, interior panels, and non-structural supports) and other consumer products like casings, furniture parts, and sporting goods.