Influence of Cordia dichotoma Fibers and Zinc Oxide Nanoparticles on the Mechanical and Thermal Behavior of Epoxy Hybrid Composites

Recently, natural fibers have been increasingly used in lightweight applications to reduce the reliance on synthetic materials. The reinforcing phase in this study consists of Cordia dichotoma fiber (CDF), while the matrix material is an epoxy polymer composite with zinc oxide (ZnO) nanofiller. To determine the mechanical properties of the hybrid composites, five composite laminates were made with different weight ratios of filler-to-fiber. The results indicate that the composite laminate sample (S1) showed better mechanical properties with a higher weight ratio of CDFs. These attributes include tensile strength (22.45 MPa), flexural strength (26.14 MPa), and impact energy absorption (25 J). Moreover, the addition of ZnO nanofiller contributed to improved thermal stability, with higher filler content elevating the degradation temperature to 454 °C. Scanning Electron Microscopy (SEM) was employed to analyze the surface interactions among the CDFs, ZnO nanofiller, and epoxy matrix, as well as to determine the failure modes of the composite laminates during mechanical testing.