Load Effects on Dynamic Viscoelasticities of Epoxy and Its Composites

摘要

Presently the dynamic viscoelasticities of fibre reinforced composites are mainly tested under the lower load than the actual condition. So this paper investigated the load effects on dynamic viscoelasticities of novolac epoxy resin casting and glass fibre reinforced plastic (GFRP) and carbon fibre reinforced plastic (CFRP) under the relatively higher loads by using EXPLORER500. Results of epoxy 648 casting show that the storage modulus increases and the loss tangent exhibits a peak with the increasing static load, while these two parameters decrease with the increasing dynamic load. These effects are more sensitive for GFRP than for 648 casting. Besides this, the higher the cure degree of epoxy resin is, the more significant the load effects are. Compared with GFRP, the load influences CFRP more strongly for storage modulus, while more weakly for loss tangent. The loss tangent of CFRP monotonically decreases without showing a peak when the static load increases.