Water absorption behavior and residual strength assessment of glass/epoxy and glass-carbon/epoxy hybrid composite

Abstract

Present investigation is aimed to study the water absorption behaviour and evaluation of residual strength of glass fibre/epoxy (GE) and alternate plies of glass- carbon/epoxy (GCE) hybrid composite. Both the composite systems were exposed to water at 70°C. Specimens were weighed after certain time periods to study the water uptake kinetic. Flexural tests were conducted after 4, 100 and 450 hours of ageing to evaluate the effect of hot water ageing on the mechanical properties of these potential materials. The water uptake kinetic was found to follow Fickian diffusion kinetic for GE as well as GCE hybrid composite but the rate of diffusion was higher for GE composite over GCE composite. The water content was also higher in GE composite over GCE composite after 450 hours of ageing. Significant decrement in flexural strength was observed with the increase in ageing time. Presence of water in the composite also imparted significant embrittlement to the matrix as reflected in the decrease in strain at peak for both the composite systems.