Mechanical and thermo‐physical properties of Cascabela thevetia–Calotropis gigantean fiber reinforced epoxy based hybrid composites

Abstract The present work reports the mechanical, thermo‐physical and water absorption properties of Cascabela thevetia (CT)– Calotropis gigantean (CG)/epoxy natural fiber hybrid composites. Using a standard hand lay‐up method the hybrid natural fiber composites was fabricated from CT and CG fibers with different fiber loading (0, 10, 20, 30, and 40 wt%) and with different weight ratio of CT and CG fibers (1:1, 1:3, and 3:1). Physical property (density), various mechanical properties (tensile, young's modulus, flexural and impact strength), thermal properties (thermogravimetric analysis, specific heat, thermal conductivity, and thermal diffusivity) and water absorption properties were evaluated. It was observed that composites with CT:CG = 3:1 fiber loading reveals highest mechanical properties as compared to 1:1 and 1:3 fiber loading ratio. Moreover, the highest properties were obtained at 20 wt% which includes 15 wt% of CT fiber and 5 wt% of CG fibers. The findings show that at all fiber loadings, the composite manufactured with CT and CG fiber in a weight ratio of 3:1 soaks less water, exhibits less thermal conductivity and thermal diffusivity with highest mechanical properties. In order to decrease energy consumption, the manufactured hybrid composites were suited for use in construction materials and automobiles.