The effect of co-creation of notches and recesses in the adhered material on the strength of single-lap adhesive joints: Experimental and numerical analysis

For decaces, many different adhesive joint geometries have been used in aerospace and automotive applications, with the idea that adhesively-bonded joints can be an alternative to traditional joining methods in aerospace applications. The single-lap joint geometry is today one of the most frequently used joint geometries in research. In this joint geometry, due to eccentric loading, peel stresses occur, which cause damage in the overlap region. Reducing these stresses increases joint strength. In this study, the strengths of single-lap joints (SLJ) obtained by creating notches and recesses of different lengths and depths in the adhered material were investigated experimentally and numerically. First, the strengths of the SLJ obtained by using different lengths and thicknesses of recesses and notches of different widths and depths in the adherend were investigated. After this examination, the strength of the joints with the best recess and notch joints together in terms of joint strength were examined. As a result, making a recess of the adherend on the outer part of the overlap region in single-lap joints increases the joint strength by approximately 29%, and making a notch increases the strength of the connection by approximately 27%. These increases in the joint strength vary according to the geometry of the recess and notch formed in the adherend. In addition, the use of both the notch and the recess in the joint improves the joint strength further. Additionally, in the presented study, experimental data were compared with numerical analysis and it was observed that the data were quite consistent with each other.