Fatigue life evaluation of adhesively bonded scarf joints

The fatigue life of adhesively bonded scarf joints with various scarf angles was analyzed experimentally in this study. Experimental results indicate that the fatigue strength increases significantly with the scarf angle of the studied specimen. The main failure modes for the specimens with small and large scarf angles are adhesive and cohesive, respectively. Additionally, the finite element method was employed to obtain the stress states within the studied scarf joint specimens, and the fatigue data of specimens with 0°/30° scarf angles and 45°/60° scarf angles were successfully correlated using the interfacial peeling stress parameter and the von Mises stress within the adhesive, respectively.

► Fatigue life data of scarf adhesive joints with various scarf angles were reported.
► The fatigue strength increases with the scarf angle of the studied specimen.
► The failure mode changes from adhesive to cohesive when the scarf angle increases.
► The finite element method was used to obtain the stress states of the scarf joints.
► The fatigue life prediction parameters are strongly dependent on the failure mode.