Strength of aluminum single-lap bonded joints in various disbond size at circular and semi-circular notches

Abstract

Applications of assembly bonded technique have been extended currently to various industrial fields. Adhesively bonded joints are widely used in the aeronautics and astronautics industry as a result of their high strength and convenience in using the single-lap joint. The geometry of bonded single-lap joint is nonlinear and causes the eccentricity due to the non-collinear applied load, which conducts to a significant stress concentration at the extremities of overlap area, where the cracks may initiate. In this article, the finite element (FE) method is used to analyze the behavior of a bonded lap joint of aluminum adherend. The comparison of stress concentration factor and stress intensity factor of crack emanating from the circular and semi-circular notches are investigated. The single-lap bonded joints were analyzed to study the combined effect of the notch and the disbond as they pertain to joint strength and failure conditions. The results show that the stress concentration factor and stress intensity factor are affected by the negative disbond effect and their values are strongly proportional to its size.