Hybrid composite laminates reinforced with glass/carbon woven fabrics for lightweight load bearing structures

Light-weight structure utilising novel design and advanced materials is one of the keys to improving the fuel efficiency and reducing the environmental burden of automotive vehicles. To ensure the low cost of applying fibre-reinforced materials in automotive vehicles, it is proposed to selectively incorporate carbon fibres to enhance glass fibre composites along main loading path. This paper investigates the influences of stacking sequence of on the strength of hybrid composites comprising materials with differing stiffness and strength. Hybrid composite laminates were manufactured using varying ratio of glass woven fabric and carbon woven fabric in an epoxy matrix. Static tests including tension, compression and three-point-bending were carried out to composite coupons containing various ratios of carbon fibres to glass fibres. The results show that hybrid composite laminates with 50% carbon fibre reinforcement provide the best flexural properties when the carbon layers are at the exterior, while the alternating carbon/glass lay-up provides the highest compressive strength. The tensile strength is insensitive to the stacking sequence. Analytical solutions are also developed and are shown to provide good correlation with the experimental data, which allow the optimisation of stacking sequence of hybrid composites to achieve the maximum strength.

► Hybrid composites with low cost and high mechanical strength were prepared.
► Analytical solutions were developed for optimal design of flexural strength.
► Failures of hybrid composites under different loading were investigated by optical microscopy.
► Tensile strength was insensitive to the stacking sequence of composite layers.
► Alternating stacking sequence provided the best compressive strength.