Effect of interface in hybrid reinforcement of flax/glass on mechanical properties of vinyl ester composites

Hybrid fiber-reinforced thermoset plastic matrix composites are increasingly being used in automotive applications, owing to their high specific strength and modulus. In this study, hybrid composites were manufactured by means of hybrid reinforcement; that is, biaxial glass and woven flax fabrics in vinyl ester resin with various stackings were created via the vacuum assisted resin transferee molding (VARTM) process. The manufactured composites were tested for their mechanical properties (tensile strength, modulus, flexural strength, and impact strength) and verified by means of morphological analysis. The results demonstrated rather unexpected phenomena, such as the tensile strength of the pure woven glass fibers (85.16 MPa) being lower than that of the hybrid composites (143.21 MPa). The flexural tests indicated that the strength (305.46 MPa) is higher for composites with glass ply at the bottom surface, and composites with glass ply on both ends exhibit high impact strength (0.145 J/mm(2)) compared to others. A water absorption test and thermo-gravimetric analysis were also performed.