Experimental and numerical investigation of balanced Boron/Epoxy single lap joints subjected to salt spray aging

The present study concerns with the experimental and analytical investigation of balanced Boron/Epoxy single lap joints subjected to tensile loading, after being exposed to an aggressive environment (salt spray chamber) in order to study the effect of a controlled corrosive environment on their strength and failure. FM94, a high strength adhesive produced by Cytec, was used for bonding. Four different overlap lengths (13, 20, 30 and 40 mm) have been tested and an extensive experimental analysis has been executed. A geometrically nonlinear, two-dimensional (2D) 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. Additionally, a numerical solution has been applied to determine the Von Mises stress distribution and a simulation for four different overlap lengths (13, 20, 30 and 40 mm) has been performed. 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. A good agreement between finite element results and experimental findings was found.