Keywords
How to Cite
Abstract
The paper presents the influence of simple structural modifications of the adherend on the fatigue properties of adhesive joints subjected to peel. The considered modifications consisted in making a chamfer and fillet on the front edge of the adherend. The purpose of such modifications was to locally increase the thickness of the adhesive layer in the area of stress concentration. Fatigue strength tests were carried out using an electrodynamic shaker at the resonant frequency of the flexible adherend. On the basis of fatigue strength tests carried out at the limited number of cycles equal to 2×106, it was shown that a local increase in the thickness of the adhesive layer in the front part of the joint allows a significant increase in the joint's fatigue lifetime and fatigue strength. The greatest effect was shown for the variant with the fillet R2. In this case, an increase in fatigue strength of 33.1% compared to the base variant was demonstrated. For the fatigue stress level of 20.25 MPa, an increase in fatigue lifetime of 337.7% was also demonstrated. Based on the conducted research, it was shown that the reason for the improvement of the fatigue properties of the joints due to the local increase in the thickness of the adhesive layer is the phenomenon of energy absorption in the frontal area of the joint. Absorption of energy that inhibits the process of fatigue results from, among others, local flexibility of the joint, as well as nucleation of cracks in the locally increased volume of the adhesive.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/)
References
Sowa, D., Czech, Z., Byczyński, Ł., Peel adhesion of acrylic pressure-sensitive adhesives on selected substrates versus their surface energies. // International Journal of Adhesion and Adhesives 49, (2014), pp. 38-43.
Lee, H., Neville, K., Epoxy Resins: Their Applications and Technology, Literary Licensing, LLC (2012).
Kowalczyk, K., Kowalczyk, A., Czech, Z., Synthesis and properties of solid structural adhesives modified in-situ using 1D and 2D-type microfillers. // International Journal of Adhesion & Adhesives, 32 (2012), pp. 76-81.
Czech, Z., Kowalczyk, A., Pełech, R., Wróbel, R., Shao, L., Bai, Y., Świderska, J., Using of carbon nanotubes and nano carbon black for electrical conductivity adjustment. // International Journal of Adhesion and Adhesives, 36 (2012), pp. 20-24.
Rosselli, F., Making the move from conventional joining to structural adhesives. // Reinforced Plastics, February (2006), pp. 42-46.
USA Patent 2004/0242835, Resolution Performance Products (2004).
Caile, D., Pascault, J.P., Tighzert, L., Reaction of a diepoxide with a diisocyanate in bulk. // Polymer Bulletin 24 (1990), pp. 23-30.
Pilawka, R., Kowalska, J., Czech, Z., Effect of 1-substituted imidazole derivatives for the curing process of epoxyisocyanate composition. // Polish Journal of Chemical Technology 15,4, (2013), pp. 1-6.
Rośkowicz, M., Wpływ lepkosprężystości klejów konstrukcyjnych na wytrzymałość połączeń klejowych. Wojskowa Akademia Techniczna, Warszawa 2013.
Domińczuk, J., Wpływ wybranych czynników konstrukcyjnych i technologicznych na wytrzymałość połączeń klejowych. // Postępy Nauki i Techniki, 10 (2011), pp. 14-26.
Rudawska, A., Chruściel, M., Wpływ sposobu przygotowania powierzchni na wytrzymałość połączeń klejowych lotniczego stopu aluminium. // Technologia i Automatyzacja Montażu, 2 (2011), pp. 42-46.
J. Godzimirski, J.; Kozakiewicz, J.; Łunarski, J.; Zielecki, W. Konstrukcyjne połączenia klejowe elementów metalowych w budowie maszyn. Oficyna Wydawnicza Politechniki Rzeszowskiej, Rzeszów 1997.
Belingardi, G., Goglio, L., Tarditi, A., Investigating the effect of spew and chamfer size on the stresses in metal/plastics adhesive joints. // International Journal of Adhesion & Adhesives 22 (2002), pp. 273-282.
You, M., Yan, Z., Zheng, X., Yu, H., Li, Z., A numerical and experimental study of adhesively bonded aluminium single lap joints with an inner chamfer on the adherends. // International Journal of Adhesion & Adhesives 28 (2007), pp. 71-76.
Lucas, F.M., Design Rules and Methods to Improve Joint Strength. Springer-Verlag, Berlin Heidelberg 2011.
Zielecki, W., Kubit, A., Badania statyczne wytrzymałości na oddzieranie połączeń klejowych. // Technologia i Automatyzacja Montażu, 4 (2014), pp. 37-40.