Mode I fracturing properties of epoxy bonding paste

The wedge-splitting method by Tschegg was applied for the investigation of mode I fracture behavior of epoxy-based adhesives. Specific fracture energy and notch tensile strength of “traditional” thickened laminating resin were measured between −40 and +45 °C and compared to those of four new trial compounds. The adhesives in bulk were investigated as well as the interfaces between these adhesives and glass fiber-reinforced plastic. The wedge-splitting method has turned out suitable for epoxy resin. The quality of thickened laminating resin was not reached by the new trial compounds. Adherend pre-treatment with laminating resin and peel ply improved interfacial properties.