Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 30135
Effects of Different Fiber Orientations on the Shear Strength Performance of Composite Adhesive Joints

Authors: Ferhat Kadioglu, Hasan Puskul

Abstract:

A composite material with carbon fiber and polymer matrix has been used as adherent for manufacturing adhesive joints. In order to evaluate different fiber orientations on joint performance, the adherents with the 0°, ±15°, ±30°, ±45° fiber orientations were used in the single lap joint configuration. The joints with an overlap length of 25 mm were prepared according to the ASTM 1002 specifications and subjected to tensile loadings. The structural adhesive used was a two-part epoxy to be cured at 70°C for an hour. First, mechanical behaviors of the adherents were measured using three point bending test. In the test, considerations were given to stress to failure and elastic modulus. The results were compared with theoretical ones using rule of mixture. Then, the joints were manufactured in a specially prepared jig, after a proper surface preparation. Experimental results showed that the fiber orientations of the adherents affected the joint performance considerably; the joints with ±45° adherents experienced the worst shear strength, half of those with 0° adherents, and in general, there was a great relationship between the fiber orientations and failure mechanisms. Delamination problems were observed for many joints, which were thought to be due to peel effects at the ends of the overlap. It was proved that the surface preparation applied to the adherent surface was adequate. For further explanation of the results, a numerical work should be carried out using a possible non-linear analysis.

Keywords: Composite materials, adhesive bonding, bonding strength, lap joint, tensile strength.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1338740

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1830

References:


[1] R.F. Gibson, Principles of Composite Materials Mechanics, New York: McGrew-Hill, Inc. 1994.
[2] A.K. Kaw, Mechanics of Composite Materials, 2nd edition, New York: Taylor & Francois Group, 2006.
[3] F.L. Mathews, and T.T. Tester, “The influence of stacking sequence on the strength of bonded CFRP single lap joints”, International Journal of Adhesion and Adhesives, vol. 5 (1), 1985), p. 13.
[4] F. Mortensen and O.T. Thomsen, “Coupling effects in adhesive bonded joints”, Composite Structures, vol. 56 (2), 2002, p. 165.
[5] W.C. de Goeij, M.J.L. van Tooren and A. Beukers, “Composite adhesive joints under cyclic loading”, Materials & Design, vol. 20 (5), 1999, p. 213.
[6] M.D. Banea and L.F.M. da Silva, “Adhesively bonded joints in composite materials: an overview”, J. Materials: Design and Applications, vol. 223, 2009, p. 1.
[7] L. Jianfeng, Y. Ying, Z. Taotao and L Zudian,” Experimental study of adhesively bonded CFRP joints subjected to tensile loads”, International Journal of Adhesion and Adhesives, vol. 57, 2015. p. 95.
[8] M.M. Abdel Wahab, “Fatigue in adhesively bonded joints: A Review”, ISRN Materials Science, vol. 2012, 2012 p. 1.
[9] J.A.M. Ferreira, P.N. Reis, J.D.M. Costa and M.O.W. Richardson, “Fatigue behaviour of composite adhesive lap joints”, Composites Science and Technology vol. 62, 2002, p. 1373.
[10] B. Haghpanah, S. Chiu, and A. Vaziri, “Adhesively bonded lap joints with extreme interface geometry”, International Journal of Adhesion and Adhesives, vol. 48, 2014, p. 130.
[11] X. Jiang, M.H. Kolstein and F.S.K. Bijlaard, “Experimental and numerical study on mechanical behavior of an adhesively-bonded joint of FRP–steel composite bridge under shear loading”, Composite structures, vol. 108, 2014, p. 387.
[12] Hysol® EA 9394, Henkel.
[13] Standard test method for flexural properties of unreinforced and reinforced plastics and electrical insulating material: ASTM D792
[14] Standard test method for apparent shear strength of single lap joint adhesively bonded specimens: ASTM 1002.