Mode I Fracture Toughness Prediction as a Function of Temperature for a High Temperature Epoxy Adhesive

Abstract

In this work, the Double Cantilever Beam (DCB) test is analysed in order to evaluate the effect of the temperature on the adhesive mode I fracture toughness of a high temperature epoxy adhesive. Cohesive zone models, in which the failure behaviour is expressed by a bilinear traction– separation law, have been used to define the adhesive behaviour and to predict the adhesive load– displacement curves as a function of temperature. The simulation response for various temperatures matched the experimental results very well. It is shown that at temperatures below the glass transition temperature (Tg), the fracture toughness, GIc, is relatively insensitive to temperature, while above Tg (at 200ºC) a drastic decrease in fracture toughness was observed.