3D FE adhesion failure analyses of adhesive bonded single lap joint made with functionally modulus graded curved adherends

Abstract

Adhesive bonded Single Lap joints (SLJ) are used to make several larger structures of several industries, including (aerospace and marine) by joining smaller laminated FRP composite panels. The Single Lap JointJ, due to its inherent overlapping geometry, possesses an eccentric load transfer path when subjected to tensile loading. The coupling of differential straining, bending, twisting and tension phenomenon induces out-of-plain peel, in-plane longitudinal shear and transverse shear stresses near the overlap ends. A small adhesion failure may be pre-existing or may onset from a vulnerable location in the Single Lap Joint. The propagation rate of this adhesion failure decides whether the jointed structure will fail slowly or catastrophically during loading. A three-dimensional adhesion failure analysis in the Single Lap Joint made with functionally modulus-graded curved adherends under uniformly applied tension is presented in this article. The peel and shear stresses in the bond line interfaces have been evaluated for different compositional gradient exponents of the material of adherends using the no-linear finite element method. The effects of the adhesion failure lengths and compositional gradient exponents on the opening, sliding and strain energy release rate (SERR) corresponding to have been evaluated to predict the structural integrity of the SLJ. The structural integrity and, hence, the service life of the adhesive-bonded single lap joint can be enhanced by the functionally graded modulus of the adherends to reduce the magnitudes of peel and shear stresses in the vicinity of the overlap ends. � The Author(s), under exclusive licence to Springer-Verlag France SAS, part of Springer Nature 2024.