Single lap bonded composite joints with interlaminar hybridisation::A two-scale finite element model

In this study, a two-scale finite element model is developed for single-lap bonded composite laminate joints to investigate the effect of interlaminar hybridization on the static behaviour of bonded joints with hybrid laminates. Hybrid laminates with uni-directional (UD) carbon fibre-reinforced plastic (CFRP) laminae and glass fibre-reinforced plastic (GFRP) laminae are considered. Single-lap bonded joints are analysed by examining different combinations of hybrid layups for the adherends (laminates). To achieve graded hybrid layup sequences, the fibre volume fractions in the CFRP and GFRP laminae are varied within the adherends. A micro-scale repeating unit cell (RUC) model is used to obtain the elastic lamina properties of the CFRP and GFRP laminae with different fibre volume fractions. A macro-scale finite element model is then developed for single-lap bonded joints with hybrid laminates. Cohesive elements are employed in the macro-scale model to account for damage initiation and propagation at the adherend-adhesive interfaces. The numerical simulation reveals that the distributions of the peel and shear stress along the adhesive bonding line change only marginally with various hybrid sequences, so does the strength of single-lap bonded joints.