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Experimental Mechanics

, Volume 37, Issue 1, pp 78–86 | Cite as

Local displacements and load transfer in shape memory alloy composites

  • K. Jonnalagadda
  • G. E. Kline
  • N. R. Sottos
Article

Abstract

Although there has been a significant amount of research dedicated to characterizing and modeling the response of shape memory alloys (SMAs) alone, little experimental work has been done to understand the behavior of SMAs embedded in a host material. The interaction between SMA wires and a host polymer matrix was investigated by correlating local displacements and stress fields induced by the embedded wires with SMA/polymer adhesion. Most SMA composite applications require transfer of strain from the wire to the matrix. In these applications, maximum interfacial adhesion between the SMA wire and the polymer matrix is most desirable. The adhesion was varied by considering four different surface treatments: untreated, acid etched, hand sanded and sandblasted. The average interfacial bond strength of the SMA wires embedded in an epoxy matrix was measured by standard pull out tests. Sandblasting significantly increased the bond strength, whereas hand sanding and acid cleaning actually reduced interface strength. In situ displacements of embedded, surface-treated SMA wires were measured using heterodyne interferometry, whereas the resulting stresses induced in the polymer matrix were investigated using photoelasticity. Increased wire adhesion resulted in lower axial wire displacement and higher interfacial stresses due to the restraining effect of the matrix on the actuated wire. A simplified theoretical analysis was carried out to estimate the shear stress induced in the matrix due to wire actuation. The maximum shear stress predicted for the case of a perfect interfacial bond was about 7 percent larger than the value measured experimentally for the sand-blasted wire.

Keywords

Polymer Matrix Bond Strength Shape Memory Alloy Interfacial Bond Maximum Shear Stress 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    Duerig, T.W. andWayman, C.M., “An Introduction to Martensive and Shape Memory,”Engineering Aspects of Shape Memory Alloys, ed, D. Stockel, T.W. Duerig, K.N. Melton andC.M. Wayman, Butterworth-Heinemann, Boston, 3–20 (1989).Google Scholar
  2. 2.
    Hodgson, D.E., Using Shape Memory Alloys, Cupertino, CA (1995).Google Scholar
  3. 3.
    Hebda, D. andWhite, S.R., “Effect of Training Conditions and Extended Thermal Cycling on Nitinol Two-way Shape Memory Behavior,”Smart Materials and Structures,4,298–304 (1995).CrossRefGoogle Scholar
  4. 4.
    Liang, C., Jia, J. and Rogers, C., “Behavior of Shape Memory Alloy Reinforced Composite Plates Part II: Results,” Proc. 30th Structures, Structural Dynamics and Materials Conf., AIAA-89-1331-CP, 1504–1513 (1989).Google Scholar
  5. 5.
    Rogers, C.A., “Active Vibration and Structural Control of Shape Memory Alloy Hybrid Composites: Experimental Results,”J. Acoustical Society of America,88, (6),2803–2811 (1990).Google Scholar
  6. 6.
    Baz, A. andRo, J., “Thermo-dynamic Characteristics of Nitinol Reinforced Composite Beams,”Composites Eng.,2,527–542 (1992).Google Scholar
  7. 7.
    Chaudry, Z. and Rogers, C.A., “Response of Composite Beams to an Internal Actuator Force,” Proc. 32th Structures, Structural Dynamics and Materials Conf., AIAA-91-1166-CP, 186–193 (1989).Google Scholar
  8. 8.
    Paine, J.S.N. andRogers, C.A., “The Effect of Thermoplastic Composite Processing on the Performance of Embedded Nitinol Actuators,”J. Thermoplastic Composite Mateirals,4 (2),102–122 (1991).Google Scholar
  9. 9.
    Hebda, D.A., Whitlock, M.E., Ditman, J.B. andWhite, S.R., “Manufacturing of Adaptive Graphite/epoxy Structures with Embedded Nitinol Wires,”J. Intelligent Materials and Smart Systems,6 (2)220–228 (1985).Google Scholar
  10. 10.
    Paine, J.S.N., Jones, W.M. and Rogers, C.A., “Nitinol Actuator to Host Composite Interfacial Adhesion in Adaptive Hybrid Composites,” Proc. 33rd Structures, Structural Dynamics and Materials Conf., AIAA-92-2405-CP, 556–565 (1992).Google Scholar
  11. 11.
    Bidaux, J.-E., Bataillard, L., Manson, J.-A. and Gotthardt, R., “Phase Transformation Behavior of Thin Shape Memory Alloy Wires Embedded in a Polymer Matrix Composite,” Proc. 3rd European Conf. Advanced Materials and Processes, Paris (1993).Google Scholar
  12. 12.
    Boyd, J.G. andLagoudas, D.C., “A Thermodynamic Constitutive Model for Shape Memory Materials, Part II The SMA composite Material,”Int. J. Plasticity,12 (7),843–873 (1996).CrossRefGoogle Scholar
  13. 13.
    Wake, W.C., “Theories of Adhesion and Uses of Adhesives: A Review,”Polymer,19,291–308 (1978).CrossRefGoogle Scholar
  14. 14.
    Paine, J. andRogers, C., “Characterization of Interfacial Shear Strength between SMA Actuators and Host Composite Material in Adaptive Composite Material Systems,”Adaptive Structures and Material Systems, vol ASME AD-35, 63–70 (1993).Google Scholar
  15. 15.
    Penn, L.S. andLee, S.M., “Interpretation of Experimental Results in the Single Pull-out Filament Test,”J. Composites Science and Technology,11 (1),23–30 (1989).Google Scholar
  16. 16.
    Piggott, M.R., “Failure Processes in Fiber-polymer Interphase,”Composite Science and Technology,42 (1),56–76 (1991).Google Scholar
  17. 17.
    Sottos, N.R., Scott, W.R. andMcCullough, R.L., “Micro-interferometry for Measurement of Thermal Displacements and Fiber/matrix Interfaces,” EXPERIMENTAL MECHANICS,31 (2),98–103 (1991).Google Scholar
  18. 18.
    Li, L., andSottos, N.R., “Measurement of Surface Displacements in 1-3 and 1-1-3 Piezocomposites,”J. Applied Physics,79 (3),1707–1712 (1996).CrossRefGoogle Scholar
  19. 19.
    Bellesis, B.H., Harlice, P.S., Renema, A., andLambeth, D.N., “Magnetostriction Measurement by Interferometry,”IEEE Transactions on Magnetics,29 (6)2989–2991 (1993).CrossRefGoogle Scholar
  20. 20.
    Ryan, M.J., Scott, W.R. andSottos, N.R., “Scanning Heterodyne Micro-interferometry for High Resolution Contour Mapping,”Review of Progress in Quantitative Nondestructive Evaluation, Plenum, New York (1990).Google Scholar
  21. 21.
    Post, D., “Fringe Multiplication in Three-dimensional Photoelasticity,”J. Strain Analysis,1, (5),380–388 (1966).Google Scholar
  22. 22.
    Tyson, W.R. andDavies, G.J., “A Photoelastic Analysis of the Shear Stresses Associated with the Transfer of Stress during Fibre Reinforcement,”British J. Applied Physics,16,199–205 (1965).Google Scholar
  23. 23.
    MacLaughlin, T.F., “A Photoelastic Analysis of Fiber Discontinuities in Composite Materials,”J. Composite Materials,2 (1),44–55 (1968).Google Scholar
  24. 24.
    Xu, Z.R. andAshbee, K.H.G., “Photoelastic Study of the Durability of Interfacial Bonding of Carbon Fibre-epoxy Resin Composites,”J. Materials Science,29,394–403 (1994).Google Scholar
  25. 25.
    Krynicki, J.W., Nagle, D.C. andGreen, R.E., Jr.Photoelastic Measurement of Residual Thermomechanical Stress in SiC-reinforced Glass Composites,”J. Am. Ceram. Society,75, (8),2225–2231 (1992).Google Scholar
  26. 26.
    Jackson, C.M., Wagner, H.J., and Wasilewski, R.J., “55-nitinol —The Alloy with a Memory: Its Physical Metallurgy, Properties, and Applications”, Technical Report SP-5110, NASA (1972).Google Scholar

Copyright information

© Society for Experimental Mechanics, Inc. 1997

Authors and Affiliations

  • K. Jonnalagadda
    • 1
  • G. E. Kline
    • 1
  • N. R. Sottos
    • 1
  1. 1.Department of Theoretical and Applied MechanicsUniversity of Illinois at Urbana-ChampaignUrbana

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