PSI - Issue 68

P.M.D. Carvalho et al. / Procedia Structural Integrity 68 (2025) 398–404 P.M.D. Carvalho et al. / Structural Integrity Procedia 00 (2025) 000–000

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In view of these results, t P2 highly affects U in all evaluated designs. The highest U improvement with t P2 was 447.1% found for DAJ 1/8 with the 2015-AV138-2015 configuration from 1 ≤ t P2 ≤ 2. Oppositely, the highest U decrease (-57.8%) was found from 3 ≤ t P2 ≤ 4 on DAJ 1/8 with the 7752-2015-7752 configuration. The best U performance was achieved with t P2 =3 mm, similar to the P m evaluation. In addition, it is also notorious that the overlap area where the ductile adhesive is applied highly affects the joint strength (best U performance for DAJ 1/3). 4. Conclusions This study explored the DAJ technique to enhance the strength of T-joints. The approach was initially validated against experimental data across various geometries, specifically varying t P2 . The maximum absolute deviations from CZM predictions were 4.7% for the 2015 and 7.2% for the 7752, confirming the reliability of the CZM method for designing peel-dominant bonded joints. Numerical DAJ analysis revealed that P m is highly dependent on t P2 , reaching 150.6% P m improvements between consecutive t P2 for a given configuration. The best performance was typically achieved by t P2 =3 mm, and relevant P m depreciations were found by further increasing t P2 to 4 mm. The best design to maximize P m was the DAJ 1/4 with the 7752-2015-7752 configuration and t P2 =3 mm. U is also mostly affected by t P2 , with a significant improvement of almost 450% between consecutive t P2 for a given design. The maximized U between all configurations pertained to t P2 =3 mm, following the P m analysis. Increasing t P2 to 4 mm was highly detrimental to U . The DAJ 1/3 with the 7752-2015-7752 configuration and t P2 =3 mm was the overall recommend design which represents a slightly different design compared to P m . In view of these results, it was possible to propose the best T-joint designs for a given material/adhesive combination, which can be extended to other bonding scenarios. References Adams, R. D., Adams, R. D., Comyn, J., Wake, W. C. and Wake, W. (1997). Structural adhesive joints in engineering, Springer Science & Business Media. Adams, R. D. and Peppiatt, N. A., 1974. Stress analysis of adhesive-bonded lap joints. The Journal of Strain Analysis for Engineering Design 9(3), 185-196. Akhavan-Safar, A., Ramezani, F., Delzendehrooy, F., Ayatollahi, M. R. and da Silva, L. F. M., 2022. A review on bi-adhesive joints: Benefits and challenges. International Journal of Adhesion & Adhesives 114, 103098. Campilho, R. D. S. G., Banea, M. D., Neto, J. A. B. P. and da Silva, L. F. M., 2013. Modelling adhesive joints with cohesive zone models: effect of the cohesive law shape of the adhesive layer. International Journal of Adhesion & Adhesives 44, 48-56. Choffat, F., Corsaro, A., Di Fratta, C. and Kelch, S. (2023). Advances in polyurethane structural adhesives. Advances in Structural Adhesive Bonding, Elsevier : 103-136. Ebnesajjad, S. and Landrock, A. H. (2014). Adhesives technology handbook. New York, USA, William Andrew. Faneco, T. M. S., Campilho, R. D. S. G., Silva, F. J. G. and Lopes, R. M., 2017. Strength and fracture characterization of a novel polyurethane adhesive for the automotive industry. Journal of Testing and Evaluation 45(2), 398-407. Ferreira, C. L., Campilho, R. D. S. G. and Moreira, R. D. F., 2020. Experimental and numerical analysis of dual-adhesive stepped-lap aluminum joints. Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering 234(5), 454-464. Ferreira, L. R. F., Campilho, R. D. S. G., Barbosa, D. R., Rocha, R. J. B. and Silva, F. J. G., 2019. Static strength improvement of tubular aluminium adhesive joints by the outer chamfering technique. Procedia Manufacturing 38, 629-636. Gajewski, J., Golewski, P. and Sadowski, T., 2021. The Use of Neural Networks in the Analysis of Dual Adhesive Single Lap Joints Subjected to Uniaxial Tensile Test. Materials 14(2), 419. Huang, J., Zeng, J., Bai, Y., Cheng, Z., Wang, Y., Zhao, Q. and Liang, D., 2021. Effect of adhesive layer properties on the shear strength of single lap structures of dissimilar materials based on the cohesive zone model. Journal of Mechanical Science and Technology 35(1), 133-143. Lambiase, F., Scipioni, S. I., Lee, C.-J., Ko, D.-C. and Liu, F., 2021. A state-of-the-art review on advanced joining processes for metal-composite and metal-polymer hybrid structures. Materials 14(8), 1890. Masoudi Nejad, R., Ghahremani Moghadam, D., Hadi, M., Zamani, P. and Berto, F., 2022. An investigation on static and fatigue life evaluation of grooved adhesively bonded T-joints. Structures 35, 340-349. Neto, J. A. B. P., Campilho, R. D. S. G. and da Silva, L. F. M., 2012. Parametric study of adhesive joints with composites. International Journal of Adhesion & Adhesives 37(0), 96-101. Petrie, E. M. (2007). Handbook of adhesives and sealants, McGraw-Hill Education. Raphael, C. (1966). Variable-adhesive bonded joints (Stresses in ordinary lap joint compared to variable adhesive joint). Structural Adhesives Bonding Symposium, Hoboken, USA. Sadeghi, M. Z., Gabener, A., Zimmermann, J., Saravana, K., Weiland, J., Reisgen, U. and Schroeder, K. U., 2020. Failure load prediction of adhesively bonded single lap joints by using various FEM techniques. International Journal of Adhesion & Adhesives 97, 102493. Volkersen, O., 1938. Die Nietkraftverteilung in zugbeanspruchten Nietverbindungen mit konstanten Laschenquerschnitten. Luftfahrtfor schung 15, 41-47. Ye, J., Yan, Y., Li, J., Hong, Y. and Tian, Z., 2018. 3D explicit finite element analysis of tensile failure behavior in adhesive-bonded composite single-lap joints. Composite Structures 201, 261-275.