Thermal Stresses in Adhesively Bonded Joints: Numerical and Analytical Analysis

The adhesive technique is observing a considerable increase in applications in various fields. Unlike traditional joining methods, this technology allows the stress peaks and the weight of the resulting structure to be reduced. Adhesive joints during their service life not only undergo mechanical but also thermal stresses. The thermal compatibility between the adhesive and the adherents used is a fundamental aspect to consider in the design phase. This paper reports on and analyses the results obtained from a linear Finite Element Method (FEM) simulation for a hybrid adhesive joint, as the thickness and characteristics of the adhesive layer vary. An analytical solution for adhesive-free joints is presented according to both beam and plate theories. The analytical and numerical results, in case of no adhesive, are in good agreement with good approximation. The introduction of the adhesive layer allows to obtain higher displacement values than in the adhesive-free configuration. The increase in displacement and therefore in ductility confirms the effectiveness of the adhesive joint for real applications.