Numerical Analysis Of Stress Distribution Of Adhesively Bonded Metal Joint Under Cleavage Loading

In this dissertation, the mechanical behavior of the metal adhesively bonded composite joints under loading have been systematically investigated by numerical calculation methods and experiments, and effects of shape dimensions and physical parameters of joints on stress distribution and strength of adhesively bonded joints have been placed emphasis upon. Based on a review of its current states and developing tendency all over the world, the thesis presents some new achievements in the theoretical analysis in this field. Components qualities of bonding technology are influenced by many factors, which is complicated. This paper evaluates the quality of bonding technology based on analytical hierarchy process, which provides theory reference for quality controlling process, and proving it proper in contact with examples.The stress distribution of adhesively-bonded metal/metal single lap joints under tensile shear loading is analysed using elastic-plastic finite element method (FEM) .The influence of lap length on the strength of adhesively bonded metal joints which are bonded with phenolic resin and acrylic resin respectively is discussed in detail. It is shown that adhesive has great influence on the stress distribution of the lap region. With the increment of lap length, the stress concentration of adhesive layer decreases.The stress distribution of adhesively bonded metal/metal single lap joints under cleavage loading has been analyzed using three-dimensional elastic or elasto-plastic finite element method (FEM), stress state in adhesive layers and adherend is complex, and there exist mostly normal stress components. There exist greater stresses at left edge of bondline than those other region in adhesive layer. However, observations have been made in particular on normal and shear stress components at the interfaces and the middle of adhesive layer and in the upper adherend 3 mm parallel to the interface of ahesive- adherend, which provides useful insight into the 3D nature of the problem. For verification, experiments were performed on the joint strength. The analytical results were consistent with the experimental ones.And the effects of adhesive thickness, elastic modulus and Poisson's ratio of adhesive or adherend, the ratio of elastic modulus of adherend to adhesive, the ratio of Poisson's ratio on the stress distribution at the interface were clarified by numerical calculation. The analysis with elasto-plastic materials'behavior was performed in order to include a more general situation. It is shown that adhesive has great influence on the stress distribution of...