Experimental Investigation of Hybrid Glass-Sisal Fiber Reinforced Polyester Composites

Abstract In this study, the experimental testing of hybrid fiber composite material was conducted to characterize the mechanical properties such as tensile, compressive, and flexural strength. To improve the mechanical properties, natural fibers such as sisal fiber was hybridized with synthetic glass fiber. The hybrid fiber was prepared by hand lay-up method with consideration of process parameters such as fiber weight ratio (30%, 35%, and 40%), fiber orientation (mat-mat-mat, unidirectional-mat-unidirectional, mat-unidirectional-mat, mat-random-mat, and random-mat-random), and ply arrangement (sisal-glass-sisal, glass-sisal-glass, and sisal-sisal-sisal) respectively to form composites. The sisal fiber surfaces were chemically treated with 10% NaOH. The treated sisal fibers and glass fibers were combined by using matrix material unsaturated polyester and the hardener (methyl ethyl ketone peroxide). The tests are carried out as per the ASTM standards. From the mechanical property tests, the result showed that 35% fiber weight ratio composite material with mat-mat-mat fiber orientation and glass-sisal-glass ply arrangement revealed the highest tensile, flexural and compressive strength when compared to other composite materials.