Effect of Different Step-Lap Joints on the Natural Frequencies of Different Adhesively Bonded Metallic Materials: A Numerical Study

Due to their many applications' benefits, adhesively bonded joints are widely utilized in nearly every industry, including space, marine, automotive, and aeronautics. Since unpredicted loadings may cause resonance in the structures, an accurate prediction of the bonded joints' dynamic characteristics is crucial. Therefore, in this study, modal analysis was performed on the two-, three-, four- and double-step adhesively bonded lap joints of Aluminum (Al), Copper (Cu), and Mild steel (Ms) materials with Epoxy Araldite adhesive. Ansys commercial program was utilized to analyze it numerically. The results showed that modeling the bonding region of single lap joints as two-, three-, and four-step adhesively bonded lap joints has no significant effect on the natural frequencies. This modeling has a minor incremental effect on the natural frequencies. However, Double-step lap joints were found to cause a considerable reduction in natural frequencies compared to not only single lap joints but also two-, three-, and four-step adhesively bonded lap joints. Double-step bonding caused a decrease of 8.82%, 8.57%, and 8.73% for Al-Al, Cu-Cu, and Ms-Ms. In general, in all models, the best increase or decrease in terms of natural frequencies was found to be Cu-Cu adhesively lap joints.