Advanced numerical methods for the strength prediction of hybrid adhesively bonded T-peel joints

Abstract

ABSTRACT The market requirements impose searching for new joining solutions, which must be simple and effective. Adhesive joints are currently used, for example in the automotive and aeronautical industries, since welding is not possible in many cases and because drilling the base materials is not required. To analyse adhesive joints, the Finite Element Method (FEM) is increasingly used. The Extended Finite Element Method (XFEM) is able to predict crack growth and joint strength in adhesive structures. However, there are still not many case studies about its suitability. On the other hand, hybrid joints, which combine spot-welding with adhesive bonding, are being increasingly used in different industries. This study has the purpose of validating the XFEM to predict the performance of T-peel hybrid joints between DIN C45E steel adherends under tensile loads. A comparison is made with spot-welded and adhesive joints. Three adhesives are tested (Araldite® AV138, Araldite® 2015 and Sikaforce® 7752). Different damage initiation and growth criteria, and also damage law shapes, were evaluated for strength and dissipated energy predictions. The joints’ performance was found to highly vary between adhesives and bonding method, and the XFEM analysis is accurate for specific modelling conditions.