Identification of Dynamic Damping Properties of a Flexible Structural Adhesive

Authors

1 Amirkabir University of Technology

2 Amirkabir University of Technology Aerospace Engineering Department Tehran-Iran

http://dx.doi.org/10.22064/tava.2015.13478

Abstract

In this paper dynamic damping properties of a nominated flexible structural adhesive have been identified using an extended-direct modal based joint identification method. It has been revealed that damping characteristics of adhesive are correlated to both frequency and mode shape. Young’s and shear moduli increase with frequency but damping on the other hand, decrease. The results showed that mode shape has an important role on the dynamic mechanical properties of adhesive. Modes that dominantly create normal stress on the adhesion surface represent higher stiffness and lower loss factor compared to shear modes. The different level of loss factors between bending modes and shear modes are notable, but damping property of bending modes and shear modes on the other hand, is in the same order and decreases with frequency. It has been shown that the effective, viscoelastic, mechanical properties of the adhesive can be identified successfully, using the suggested method of identification.

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1 .R.D. Adams, J. Comyn, W.C. Wake, Structural Adhesive Joints in Engineering, Elsevier Applied Science Publishers, London, 1997
2 .R.W. Messler, Joining of Advanced Materials,  Butterworth-Heinemann, Boston, 1993
3 . A. Dellard, Advances in Structural Adhesive Bonding, Wood head Publishing Limited, Cambridge, London, 2010
4 .H. Xiaocong, A review of finite element analysis of adhesively bonded joints, Int. J. Adhes. Adhes., 31(2011) 248-264.
 
5 .L. Gaul, S. Bohlen, Identification of nonlinear structural joint models and implementation in discretized structure models, Proceeding of the 11th ASME Conference on mechanical vibration and noise, Boston, USA, (1987) 213-219.
6 .S.M.S. Sadati, A.S. Nobari, T. Naraghi, Identification of a nonlinear joint in an elastic structure using optimum equivalent linear frequency response function. Acta Mech. 223 (2012)1507-1516.
7 .A.S. Nobari, D.A. Robb, D.J. Ewins, A new approach to modal-based structural dynamic model updating and joint identification. Mechanical systems and signal processing 9(1)(1995) 85-100.
8 .M.M. Meshki, A.S. Nobari, K. Nikbin, Study of surface bonding imperfection effects on equivalent identified dynamic Young’s and shear moduli using a modal based joint identification method", MSSP. (2014)
9 .A.S. Nobari, K. Jahani, Identification of Damping Characteristic of a Structural Adhesive by Extended Modal Based Direct Model, Exp. Mech. 49(2009)785-798.
10 .Sikaflex-255FC, Technical data sheet, http://usa.sika.com/dms/getdocument.get/5d88ecdb-803a-368a-9a8a-3a43bb2ec065/ipd-pds-sikaflex255FC-us.pdf