Experimental Mechanics

, Volume 26, Issue 2, pp 175–184 | Cite as

The influence of fiber length and fiber orientation on damping and stiffness of polymer composite materials

  • S. A. Suarez
  • R. F. Gibson
  • C. T. Sun
  • S. K. Chaturvedi
Article

Abstract

This paper describes the theoretical analysis, the experimental results and the curve-fitting of the analytical model to the experimental results on the influence of fiber length and fiber orientation on damping and stiffness of polymer-composite materials. The experimental results show that, as predicted, very low fiber aspect ratios are required to produce significant improvements in damping. Measurements and predictions also indicate that the control of lamina orientation in a continuous fiber-reinforced laminate may be a better approach to the improvement of damping than the control of the fiber aspect ratio.

Keywords

Polymer Mechanical Engineer Aspect Ratio Composite Material Fluid Dynamics 

List of Symbols

Ef*

complex-extensional modulus for the fiber

EfT*

complex-transverse modulus for the fiber

EL*

composite extensional-complex modulus

Em*

complex modulus for the matrix

ET*

composite transverse-complex modulus

Ex*

composite complex modulus along the loading direction

E′f, E″f

extensional storage and loss moduli for the fiber

E′L, E″L

extensional storage and loss moduli for the composite

E′m, E″m

extensional storage and loss moduli for the matrix

GLT

in-plane shear modulus for the composite

GfLT*

complex in-plane shear modulus for the anisotropic fiber

Gm*

complex shear modulus for the matrix

K*

generalized complex viscoelastic constant, or complex modulus

K′

generalized storage modulus

K″

generalized loss modulus

fiber length

(ℓ/d)

fiber aspect ratio

(ℓ/d)eff

effective fiber aspect ratio

M

composite modulusET orGLT

Mf

fiber modulusEf orGf

Mm

matrix modulusEm orGm

r0

fiber radius

vf

fiber-volume fraction

vm

matrix-volume fraction

Z

curve-fitting parameter for fiber aspect ratio

β

parameter defined in eq (2)

ηf

fiber-loss factor

ηh,ηh*1ηh*2

parameters defined in eqs (6), (11) and (13)

ηm

matrix loss factor

θ

angle of the fibers with respect to the direction of the applied load

φ1, φ2

functions defined in eq (9)

Vf

fiber Poisson's ratio

VLT

composite major Poisson's ratio

ξ, ξ1, ξ2

Halpin-Tsai parameters

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Gibson, R.F., “Development of Damping Composite Materials,” 1983 Advances in Aerospace Structures, Materials and Dynamics, AD-06, Amer. Soc. Mech. Eng., 89–95 (1983).Google Scholar
  2. 2.
    Gibson, R.F., Chaturvedi, S.K. andSun, C.T., “Complex Moduli of Aligned Discontinuous Fibre-Reinforced Polymer Composites,”J. Mat. Sci.,17,3499–3509 (1982).CrossRefGoogle Scholar
  3. 3.
    Sun, C.T., Gibson, R.F. andChaturvedi, S.K., “Internal Damping of Polymer Matrix Composites Under Off-Axis Loading,”J. Mat. Sci.,20,2575–2585 (1985).CrossRefGoogle Scholar
  4. 4.
    Schultz, A.B. andTsai, S.W., “Dynamic Moduli and Damping Ratios in Fiber-Reinforced Composites,”J. Comp. Mat.,2 (3),368–379 (1968).Google Scholar
  5. 5.
    Adams, R.D. andBacon, D.G.C., “Effect of Fibre Orientation and Laminate Geometry on the Dynamic Properties of CFRP,”J. Comp. Mat.,7,402–428 (1973).Google Scholar
  6. 6.
    Ni, R.G. andAdams, R.D., “The Damping and Dynamic Moduli of Symmetric Laminated Composite Beams-Theoretical and Experimental Results,”J. Comp. Mat.,18,104–121 (1984).Google Scholar
  7. 7.
    Chang, S. andBert, C.W., “Analysis of Damping for Filamentary Composite Materials,”Composite Materials in Engineering Design, Amer. Soc. for Met., Metals Park, OH, 51–62 (1973).Google Scholar
  8. 8.
    Gibson, R.F. andPlunkett, R., “Dynamic Mechanical Behavior of Fiber-Reinforced Composites: Measurement and Analysis,”J. Comp. Mat.,10,325–341 (1976).Google Scholar
  9. 9.
    Suarez, S.A., Gibson, R.F. andDeobald, L.R., “Random and Impulse Techniques for Measurement of Damping in Composite Materials,”Experimental Techniques,8 (10)19–24 (Oct. 1984).Google Scholar
  10. 10.
    Suarez, S.A. and Gibson, R.F., “Computer-Aided Dynamic Testing of Composite Materials,” Proc. 1984 SEM Conf. on Exp. Mech., Milwaukee, WI, 118–123 (1984).Google Scholar
  11. 11.
    Cox, H.L., “The Elasticity and Strength of Paper and Other Fibrous Materials,”Brit. J. Appl. Phys.,3,72–79 (1952).CrossRefGoogle Scholar
  12. 12.
    Chamis, C.C., “Mechanics of Load Transfer at the Interface,”Composite Materials,6,Academic Press,New York (1974).Google Scholar
  13. 13.
    Hashin, Z., “Complex Moduli of Viscoelastic Composites. I. General Theory and Application to Particulate Composites,”Int. J. Solids and Struct.,6,539–552 (1970).MATHGoogle Scholar
  14. 14.
    Jones, R.M., Mechanics of Composite Materials, Scripta Book Co. (1975).Google Scholar
  15. 15.
    Suarez, S.A., Optimization of Internal Damping in Fiber Reinforced Composite Materials, PhD dissertation, Univ. of Idaho (Dec. 1984).Google Scholar
  16. 16.
    Hashin, Z., “Analysis of Properties of Fiber Composites with Anisotropic Constitutents,”J. Appl. Mech.,46,543–550 (Sept. 1979).MATHGoogle Scholar
  17. 17.
    Whitney, J.M., “Elastic Moduli of Unidirectional Composites with Anisotropic Filaments,”J. Comp. Mat.,1,188–193 (1967).Google Scholar
  18. 18.
    Gibson, R.F., Deobald, L.R. andSuarez, S.A., “Laboratory Production of Discontinuous-Aligned Fiber Composite Plates Using an Autoclave-Style Press Cure,”J. Comp. Tech. and Res.,7 (2),49–54 (Summer 1985).Google Scholar
  19. 19.
    DiCarlo, J.A., “The Fiber Contribution to Composite Damping,” presented at Symp. on the Role of Surfaces and Interfaces in Material Damping, 1985 ASM Met. Cong., Toronto, Canada (Oct. 1985).Google Scholar
  20. 20.
    Hwang, S.L., “Finite Element Modeling of Damping in Discontinuous Fiber Composite Materials,” MS Thesis, Univ. of Idaho (1985).Google Scholar
  21. 21.
    Hwang, S.L. and Gibson, R.F., “Micromechanical Modeling of Damping in Discontinuous Fiber Composites Using a Strain Energy/Finite Element Approach,” Paper 85-WA/Mats-3, presented at ASME Winter Annual Mtg., Miami Beach, FL (Nov. 1985).Google Scholar

Copyright information

© Society for Experimental Mechanics, Inc. 1986

Authors and Affiliations

  • S. A. Suarez
    • 1
  • R. F. Gibson
    • 1
  • C. T. Sun
    • 2
  • S. K. Chaturvedi
    • 3
  1. 1.Mechanical Engineering DepartmentUniversity of IdahoMoscow
  2. 2.Department of Engineering SciencesUniversity of FloridaGainesville
  3. 3.Civil Engineering DepartmentOhio State UniversityColumbus

Personalised recommendations