Experimental Investigation of the Effect of Curing Pressure on Strength of Single Lap Adhesive Joints

Abstract

It is a common method to apply a certain pressure to the bonded surfaces while bonding. In this way, it is ensured that the adhesive covers all surfaces and the air in the adhesive is evacuated. However, the effects of pressure changes on the curing process and mechanical properties, especially in adhesives that harden by chemical reaction, are an issue that should be handled with numerical data at a scientific level. When the literature is examined, there are limited studies on the effects of curing pressure on mechanical properties of adhesive joints. In this study, the effect of curing pressure on bond strength in adhesive joints was investigated experimentally. Single lap adhesive joints were manufactured using steel plate and DP460 epoxy. At this stage, bonding joints with different curing pressure conditions were obtained by placing weights on the adhesive area. The samples were subjected to tensile tests. In consequence of the experiments, a reducing in the joint endurance was observed after a certain pressure value. Thus, it has been understood that the pressure applied to the adhesive area affects the curing process, and must be taken within certain limits.

Keywords

• Adhesive joints
• Curing pressure
• Epoksi adhesive
• Single lap joint

References

1. [1] M.Ş. Adin, E. Kılıçkap, "Strength of double-reinforced adhesive joints," Materials Testing, vol. 63, no. 2, pp. 176-181, Feb. 2021.
2. [2] H.B. Rachid, D. Noureddine, B. Benali, M.Ş. Adin, “Effect of nanocomposites rate on the crack propagation in the adhesive of single lap joint subjected to tension,” Mechanics of Advanced Materials and Structures, pp. 1-9, Mar. 2023.
3. [3] İ. Saraç, “Failure analysis of simple overlap bonding joints and numerical investigation of the adhered tip geometry effect on the joint strength,” Materials Testing, vol. 63, no. 11, pp. 1007-1011. Nov. 2021.
4. [4] J.K. Kim, D.G. Lee, “Effects of applied pressure and temperature during curing operation on the strength of tubular single-lap adhesive joints,” Journal of Adhesion Science and Technology, vol. 18, no. 1, pp. 87-107, Apr. 2004.
5. [5] D.N. Markatos, K.I. Tserpes, E. Rau, S. Markus, B. Ehrhart, S. Pantelakis, “The effects of manufacturing-induced and in-service related bonding quality reduction on the mode-I fracture toughness of composite bonded joints for aeronautical use,” Composites Part B: Engineering, vol. 45, no. 1, pp. 556-564, Feb. 2013.
6. [6] T. Şekercioğlu, “Makine Elemanları Hesap Şekillendirme,” Birsen Publisher İstanbul, 2018.
7. [7] T. Şavaşkan, “Malzeme Bilimi ve Malzeme Muayenesi,” Papatya Publisher, İstanbul, 2018.
8. [8] A. Rudawska, “The influence of curing conditions on the strength of adhesive joints,” The Journal of Adhesion, vol. 96, no. 1, pp. 402-422, Aug. 2019.

9. [9] İ. Saraç, H. Adin, Ş. Temiz, “Experimental determination of the static and fatigue strength of the adhesive joints bonded by epoxy adhesive including different particles,” Composites Part B: Engineering, vol. 155, pp. 92-103, Dec. 2018.
10. [10] K. Matsui, “Effects of curing conditions and test temperatures on the strength of adhesive-bonded joints,” International Journal of Adhesion and Adhesives, vol. 14, no. 4, pp. 277-284, Oct. 1990.
11. [11] A. Agha, F. Abu-Farha, “Experimental methods to capture curing induced effects in adhesive bonded joints,” International Journal of Adhesion and Adhesives, vol. 104, pp. 102735, Jan. 2021.
12. [12] A.Tran, J. Konnerth, H.W. Van Herwijnen, W. Gindl-Altmutter, “Low temperature and moisture dependent curing behavior of selected wood adhesives,” International Journal of Adhesion and Adhesives, vol. 117, pp. 103178, Sept. 2022.
13. [13] M. Voss, J. Haupt, “Accelerated curing of adhesively bonded G-FRP tube connections—Part I: Experiments,” Composite Structures, vol. 268, pp. 113999, Jul. 2021.
14. [14] I. Morfini, L. Goglio, G. Belingardi, S.A. Nassar, “Effect of autoclave cure time and bonded surface roughness on the static and fatigue performance of polyurethane film Adhesive Single lap joints,” International Journal of Adhesion and Adhesives, vol. 92, pp. 37-43, Jul. 2019.
15. [15] F. Marchione, G. Chiappini, P. Munafò, “Effect of temperature and relative humidity on the shear performance of double-lap adhesive joints between steel and glass adherends,” Journal of Building Engineering, vol. 45, pp. 103546, Jan. 2022.
16. [16] Y. Jahani, M. Baena, C. Barris, R. Perera, L. Torres, “Influence of curing, post-curing and testing temperatures on mechanical properties of a structural adhesive,” Construction and Building Materials, vol. 324,pp. 126698, March 2022.
17. [17] A.I.M. Foletti, J.S. Cruz, A.P. Vassilopoulos, “Fabrication and curing conditions effects on the fatigue behavior of a structural adhesive,” International Journal of Fatigue, vol. 139, pp. 105743, Oct. 2020.
18. [18] R. Mengel, J. Häberle, M. Schlimmer, “Mechanical properties of hub/shaft joints adhesively bonded and cured under hydrostatic pressure,” International Journal of Adhesion and Adhesives, vol. 27, no. 7, pp. 568-573, Oct. 2007.
19. [19] M.D. Aydın, Ş. Temiz, A. Özel, “Effect of curing pressure on the strength of adhesively bonded joints,” Journal of Adhesion, vol. 83, no. 6, pp. 553-571, Jul. 2007.
20. [20] S. Akpinar, “The strength of the adhesively bonded step-lap joints for different step numbers,” Composites Part B: Engineering, vol. 67, pp. 170-178, Dec. 2014.
21. [21] M.S. Kim, H.T. Kim, Y.H. Choi, J.H. Kim, S.K. Kim, J.M.A. Lee, “A new computational method for predicting ductile failure of 304L stainless steel,” Metals, vol. 12, no. 8, pp. 1309, Aug. 2022.
22. [22] L.P. DeMejo, D.S. Rimai, L.H. Sharpe, “Fundamentals of Adhesion and Interfaces, ” Gordon and Breach Science Publishers, 1995.
23. [23] J. Schultz, M. Nardin, “Theories and mechanisms of adhesion,” Materials engineering-New York, vol. 14, pp. 1-26, 1999.