DOI QR코드

DOI QR Code

Boundary element analysis of singular thermal stresses in a unidirectional laminate

  • Lee, Sang Soon (Mechanical Engineering Department, Korea Atomic Energy Research Institute) ;
  • Kim, Beom Shig (Mechanical Engineering Department, Korea Atomic Energy Research Institute)
  • Published : 1997.11.25

Abstract

The residual thermal stresses at the interface corner between the elastic fiber and the viscoelastic matrix of a two-dimensional unidirectional laminate due to cooling from cure temperature down to room temperature were studied. The matrix material was assumed to be thermorheologically simple. The time-domain boundary element method was employed to investigate the nature of stresses on the interface. Numerical results show that very large stress gradients are present at the interface corner and this stress singularity might lead to local yielding or fiber-matrix debonding.

Keywords

References

  1. Griffin, Jr., O.H. (1983), "Three-dimensional curing stresses in symmetric cross-ply laminates with temperature-dependent properties", J. of Composite Materials, 17, 449-463. https://doi.org/10.1177/002199838301700506
  2. Hahn, H.T. (1976), "Residual stresses in polymer matrix composite laminates", J. Composite Materials, 10, 266-277. https://doi.org/10.1177/002199837601000401
  3. Hahn, H.T. and Pagano, N.J. (1975), "Curing stresses in composite laminates", J. Composite Materials, 9, 91-106. https://doi.org/10.1177/002199837500900110
  4. Kim, R.Y. and Hahn, H.T. (1979), "Effect of curing stresses on the first ply-failure in composite laminates", J. Composite Materials, 13, 2-14. https://doi.org/10.1177/002199837901300101
  5. Lee, S.S. (1995), "Time-domain boundary element analysis of viscoelastic solids using realistic relaxation functions", Computers & Structures, 55, 1027-1036. https://doi.org/10.1016/0045-7949(94)00507-Y
  6. Lee, S.S. and Sohn, Y.S. (1994), "Visocoelastic analysis of residual stresses in a unidirectional laminate", Structural Engineering and Mechanics, 2, 383-393. https://doi.org/10.12989/sem.1994.2.4.383
  7. Lee, S.S. and Westmann, R.A. (1995), "Application of high-order quadrature rules to time-domain boundary element analysis of viscoelasticity", Int. J. Numerical Methods in Engineering, 38, 607-629. https://doi.org/10.1002/nme.1620380407
  8. Roy, A. and Murthy, P.N. (1976), "Viscoelastic analysis of the residual stress in glass fiber reinforced plastics", Fiber Science and Technology, 9, 81-101. https://doi.org/10.1016/0015-0568(76)90014-2
  9. Weitsman, Y. (1979), "Residual thermal stresses due to cool-down of epoxy-resin composite", J. Appl. Mech., 46, 563-567. https://doi.org/10.1115/1.3424606
  10. Weitsman, Y. and Harper, B.D. (1982), "Optimal cooling of cross-ply composite laminates and adhesive joints", J. Applied Mechanics, 49, 735-739. https://doi.org/10.1115/1.3162610