Effects of Hot-Water Aging on the Compression Properties of E-Glass/Epoxy Composites at Varying Strain Rates

The effects of hot-water aging on the quasi-static and dynamic compression properties of unidirectional E-glass/epoxy laminates were investigated. E-glass/epoxy specimens were aged in water at 60°C for 4900 h and then aged and unaged specimens were tested in compression at a rate of 1.3·10 –3 s –1 and by a split Hopkinson pressure bar apparatus at varying strain rates. Their diffusion behavior was successfully described by the two-stage model whose parameters were found by the nonlinear regression method. The strain-rate-sensitivity of aged and unaged E-glass-reinforced epoxy specimens in the longitudinal direction was studied. Their dynamic and static compression properties were compared for specimens with the same dimensions. Empirical models were proposed to predict dynamic properties as functions of strain rate. SEM micrographs showed a low degradation of the resin matrix and fiber-matrix interface at hot-water aging for a time up to 4900 h.