Progression of Bending Fatigue Damage around a Discontinuity in Glass/Epoxy Composites

Abstract

The progression of bending fatigue damage around a discontinuity in spring orientation glass fiber reinforced epoxy was investigated. The specimens contained circular holes of two different hole diameter/specimen width ratios. Bending fatigue tests were performed by applying a constant maximum deflection at the end of the cantilever type specimen. The extent of delamination and internal cracking was observed using visual and scanning electron microscopy. The reduction in stiffness during fatigue cycling was linearly related to the total delamination size, independent of the maximum applied load. It was also determined that the relative size of the hole had no significant effect on the bending fatigue life.