Mechanical Behaviour of Hygrothermally Conditioned FRP Composites After Thermal Spikes

Abstract

The effect of absorbed moisture on the mechanical properties of E-Glass/Epoxy composite was investigated. It is now well known that the exposure of polymeric composites in moist environments, under both normal and sub-zero conditions, leads to certain degradation of its mechanical properties which necessitates proper understanding of the correlation between the moist environment and the structural integrity. Environments similar to several that in real life, like marine environments, the high temperature excursions (thermal spikes) experienced by the undercarriage of VTOL aircraft, or even natural weathering conditions were tried to be regenerated and an attempt was made to understand their impact on the fiber-matrix adhesion property. The tensile and bending properties were determined under hydrothermal conditions and the effect of thermal spike on the interlaminar shear strength (ILSS) values of the composite under different conditions were also discussed. The changes in glass transition temperature (Tg) and investigations through scanning electron microscopy (SEM) showed that E-Glass/epoxy composites quite sensitive to environmental conditioning.