Analytical Evaluation of Residual Stress Singularity with Interfacial Slip in Dissimilar Material Bonded Joints

Abstract

It is important to obtain information on the effect of interfacial slip on the interfacial stress field, which is induced by the thermal activation processes in the bonding process of dissimilar materials, for performing interfacial fracture analysis. In this paper, the effect of the interfacial slip occuring in the bonding processes of dissimilar materials on the stress singularity near the free edge was studied by thermoelastic finite-element method (FEM), and the characteristics of interfacial mechanics were simulated by modified bond-element method, of which fundamental types were often used for contact problems. The results are as follows. When the slip occurred near the bonded free edge, another singular stress field was produced at the slip tip, although the interfacial slip releaved the singular stress at the free edge, and the order of the singular term was found to decrease as the slip region extended. For this reason, if the interfacial slip did not accompany interfacial peel, the interfacial slip occurring in bonding processes would be effective in preventing interfacial fracture in cooling periods of bonding processes. In addition, since the stress field was found to resemble a crack problem, the singular stress field was estimated by stress intensity factor K.