Effect of Intra-Ply Hybridization of Carbon-Aramid/Epoxy Laminates under Tension-Tension Fatigue Loading

The objective of the research is to investigate the fatigue life of intra-ply hybrid Carbon-Aramid laminate with Epoxy resin in on-axis and off-axis directions. Three different off-axis angles of 15°, 30° and 45° were considered for the present work. The intra-ply hybridization is used to combine the superior mechanical properties of Carbon fibre with excellent elongation-to-failure property of Aramid fibre in the same lamina. The fatigue test was performed using load control using a frequency of 5Hz. The fatigue behaviour was studied for Carbon/Epoxy, Aramid/Epoxy, Carbon-Aramid/Epoxy, Carbon-Aramid/Epoxy - 15°, Carbon-Aramid/Epoxy - 30° and Carbon-Aramid/Epoxy - 45° with the stress ratio of R = 0.1. The ultimate tensile strength decreases progressively for Carbon/Epoxy, Carbon-Aramid/Epoxy, Aramid/Epoxy, Carbon-Aramid/Epoxy - 15°, Carbon-Aramid/Epoxy - 30° and Carbon-Aramid/Epoxy - 45°. The effect of off-axis loading indicates that the increase of fibre angle influences the decrease in tensile strength and fatigue life.