Cleavage strength of steel/composite joints

This paper presents the experimental results of an on-going study to examin e cleavage strength, particularly at the interface regions of epoxy adhesiv e with steel and glass reinforced epoxy (GRE) composite. The adhesion is ch aracterised by mechanical testing of cleavage specimens. A standard specime n was modified to allow testing of hybrid joints. The effects of adhesive t hickness and Various surface conditions of both adherends were examined. Am ong key conclusions, the study found that cleavage strength is not strongly dependent upon adhesive thickness and that polished composite gives better adhesion compared with polished steel. Test results were analysed and comp ared with aspects of numerical analyses. The study has also established a n ew methodology to test hybrid adhesive cleavage joints.