The effects of water aging on the mechanical properties of glass-fiber and kevlar-fiber epoxy composite materials

Abstract

This paper presents the results of experimental in-vestigations of composite materials on the effects of water aging. The experimental investigation was conducted un-der longitudinal tension for different cross-ply laminates constituted of glass fibers, Kevlar fibers and resin epoxy. Static and fatigue properties were investigated in the first stage. Stiffness degradation approach is used to study the mechanical behaviour of composite materials in fatigue tests. The interactions between hydrothermal aging and fatigue damage in composite were studied in the second stage. The static strength and residual stiffness were evalu-ated in static tests after fatigue of specimens at different cycle numbers and aged in tap water.