The present study focusses on the experimental and analytical investigation of unbalanced Boron/Epoxy-Aluminum 2024 T3 single lap joints subjected to tensile loading, after being exposed to a corrosive environment (salt spray chamber) in order to study its effects on their strength and failure. FM94, high strength adhesive, was used for bonding. Different overlap lengths have been tested and an extensive experimental analysis has been executed. A geometrically nonlinear, two-dimensional finite element analysis has been employed to determine the hydrostatic stress and the shear strain distribution across the two interfaces of the single-lap joints, for four different overlap lengths. The results mainly prove that the overlap length and the aging conditions directly affect the joint tensile strength, while an optimum value of the overlap length can be defined. The maximum shear and normal stresses are found to increase as the overlap length increases, but the lap shear strength is not proportional to the overlap length. A good agreement between finite element results and experimental findings was found.

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The present study concerns with the effect of bending moment coefficient in the stress distribution in a balanced boron/epoxy single lap joints subjected to tensile loading. The main feature of the single lap joint is the eccentric loading path, which results in large deflections of the outer adherend and the overlap, and the joint edge moment or bending moment coefficient at the end of the overlap. Theoretical models such as Goland–Reissner, Oplinger and Hart-Smith are examined in detail for different l/c and η/t ratios. Four different overlap lengths have been analysed. A geometrically non-linear, two-dimensional finite element analysis is also performed to provide useful comparisons with the theoretical analysis. The analytical results mainly prove that the Oplinger's model is the most appropriate for the specific geometry and materials, and the values of the bending moment coefficient are compared with the additional model of Zhao for four different l/c ratios.

A study was conducted to investigate the bending moment coefficient in unbalanced boron/epoxy–aluminium single lap joints subjected to tensile loading. It is well known that the main feature of the single lap joint is the eccentric loading path, which results in large deflections of the outer adherend and the overlap. In addition, the joint edge moment or bending moment coefficient at the end of the overlap is a significant feature. Four different overlap lengths (13, 20, 30 and 40 mm) have been analysed. A geometrically non-linear, two-dimensional finite element analysis was also performed to provide useful comparisons with the theoretical analysis. The analytical results mainly proved that, as the overlap length increases, the bending moment coefficient mainly decreased at the stiffer adherend, while the maximum l/c ratio is also decreased. The latter conclusions show that unbalanced (asymmetrical) single lap joints should be designed and manufactured with extreme care.