Temperature effects on tensile and bending properties of carbon/Kevlar hybrid fiber sandwich composites

In this paper, the mechanical properties of carbon/Kevlar hybrid fiber-reinforced resin composites at different temperatures were studied. The hybrid composites were prepared by Vacuum Assisted Resin Infusion (VARI). The sandwich structure of reinforcement consists of Kevlar plain weave fiber as a surface layer and carbon fiber plain weave fabric as a core layer, while the matrix consists of a curing agent and epoxy resin. The bending and tensile properties of the composite specimens were tested at different temperatures using the in situ testing method, separately. The fracture morphology was analyzed using scanning electron microscopy (SEM) to understand the damage mechanism of the material properties at the micro-scales. The results show that the sandwich composite material shows a positive hybrid effect. The carbon fibers increases effectively the strength and rigidity of the sample, while Kevlar fiber improves the toughness and brittle damage mode. The mechanical properties of hybrid composite laminates are strongly dependent on temperature. The tensile and bending properties of carbon/Kevlar hybrid composites decreased when the temperature increased from -30 degrees C to 40 degrees C. The effect of temperature on the bending properties was more pronounced for the carbon/Kevlar hybrid composites. This study consists of damage analysis and variation analysis of the mechanical behavior of carbon/Kevlar composite specimens, which will lay the foundation to provide basic data for the application of carbon/Kevlar hybrid composites.Highlights Advantages of carbon/Kevlar hybrid sandwiched structure on tensile and bending properties. Comprehensive mechanical property testing in multiple composite environments. Based on the hybrid effect and temperature effect, the damage mechanism of the sample was analyzed.