On quasi-static large deflection of single lap joints under transverse loading: Fid-Bau Portal

On quasi-static large deflection of single lap joints under transverse loading

Sun, Guangyong / Wei, Yang / Huo, Xintao / Luo, Quantian / Li, Qing

Abstract This study aims to characterize the mechanical behavior of a carbon fiber reinforced plastics (CFRP)/aluminum (Al) adhesive bonded single lap joint (SLJ) subjected to transversal three-point bending load with different adherend materials and kinematic boundary conditions. The experimental results divulged that the boundary conditions had noticeable influence on the load bearing capacity of the joint; and the stiffness and peak load for the fixed-support condition were much higher than those for the simply-supported condition. The stress distribution in the adhesive layer varies under different boundary conditions, leading to the different morphology of the residual adhesive at the fracture surface. The different cracks in the adhesive layer were further analyzed by SEM under peel stress and shear stress loadings. The finite element (FE) models were developed by using the material properties characterized in-house here. It is found that the load displacement curves and the crack energies predicted by finite element analysis (FEA) was well correlated with those measured by the experiment in the designated four groups of adhesive joints. This study is anticipated to provide systematic understanding of adhesive joints with dissimilar adherend materials under different boundary conditions subject to transverse loading.

Graphical abstract Display Omitted

Highlights • Comparison of the carrying capacity of two boundary conditions. • Accurate overlap strain field during loading measured by digital image correlation. • Analytical approach explains the internal causes of the experimental results. • Failure mechanism of two boundary conditions revealed by SEM analysis. • Effective finite element model based upon cohesive zone model predicts accurately.