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Plastic Response of Thin Films Due to Thermal Cycling

  • Lucia Nicola
  • Erik Van der Giessen
  • Alan Needleman
Conference paper
Part of the Solid Mechanics and Its Applications book series (SMIA, volume 114)

Abstract

Discrete dislocation simulations of thin films on semi-infinite substrates under cyclic thermal loading are presented. The thin film is modelled as a two-dimensional single crystal under plane strain conditions. Dislocations of edge character can be generated from initially present sources and glide in the film on a given set of slip systems. At each time step of the simulation, the stress field in the film is calculated through the solution of a boundary value problem, taking into account the long-range stress contribution of the current dislocation structure. The numerical results show a clear size effect in the plastic behaviour of two films with thicknesses of 0.25µm and 0.5µm. The mechanical response of the two films during the cyclic thermal loading is analysed, with an emphasis on the evolution of the dislocation structure.

Keywords

Thin films thermal cycling discrete dislocation plasticity 

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References

  1. [1]
    O.S. Leung, A. Munkholm, S. Brennan, and W.D. Nix, “A search for strain gradients in gold thin films on substrates using x-ray diffraction”, J Appl. Phys., vol. 88, pp. 1389–1396, 2000.CrossRefGoogle Scholar
  2. [2]
    M. Hommel and O. Kraft, “Deformation behavior of thin copper film on deformable substrates”, Acta Mater., vol. 49, pp. 3935–3947, 2002.CrossRefGoogle Scholar
  3. [3]
    R. Venkatraman and J.C. Bravman, “Separation of film thickness and grain boundary strengthening effects in Al thin films on Si”, J. Mat. Res., vol. 7, pp. 2040–2048, 1992.CrossRefGoogle Scholar
  4. [4]
    N.A. Reck and J.W. Hutchinson, “Strain gradient plasticity”, Adv. Appl Mech, vol. 33, pp. 295–361,1997.CrossRefGoogle Scholar
  5. [5]
    N.A. Fleck and J.W. Hutchinson, “A reformulation of strain gradient plasticity”, J. Mech. Phys. Solids, vol. 49, 2245–2271, 2001.CrossRefGoogle Scholar
  6. [6]
    M.E. Gurtin, “A gradient theory of single-crystal viscoplasticity that accounts for geometrically necessary dislocations”, J. Mech. Phys. Solids, vol. 50, pp. 5–32, 2002.CrossRefGoogle Scholar
  7. [7]
    L.B. Freund, “The stability of dislocations threading a strained layer on a substrate”, J. Appl. Mech., vol. 54, pp. 553–557,1987.CrossRefGoogle Scholar
  8. [8]
    W.D. Nix, “Yielding and strain hardening of thin metal films on substrates”, Scripta Mater., vol. 39, 545–554,1998.CrossRefGoogle Scholar
  9. [9]
    L. Nicola, E. Van der Giessen, and A. Needleman, “A discrete dislocation analysis of size effects in thin films”, (submitted).Google Scholar
  10. [10]
    E. Van der Giessen and A. Needleman, “Discrete dislocation plasticity: a simple planar model”, A. Simul. Mater. Sci. Eng., vol. 3, pp. 689–735, 1995.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media Dordrecht 2004

Authors and Affiliations

  • Lucia Nicola
    • 1
  • Erik Van der Giessen
    • 1
  • Alan Needleman
    • 2
  1. 1.The Netherlands Institute for Metals Research/Dept. of Applied PhysicsUniversity of GroningenGroningenThe Netherlands
  2. 2.Division of EngineeringBrown UniversityProvidenceUSA

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