Skip to main content

Advertisement

SpringerLink
Log in

Experimental study of the failure mechanism and strength characteristics of fiber bundles and composites

Authors establish experimentally the effect of the rate of loading on the mode and load at fracture of bundles of glass fibers and of glass-fiber-reinforced epoxy plates subjected to various quasi-static rates of tensile loading in the direction of fibers

  • Published:
Experimental Mechanics Aims and scope Submit manuscript

Abstract

The primary aim of this investigation was to establish the strength characteristics of S-glass fiber bundles and composites subjected to quasi-static loading. Ten glass-bundle specimens and glass-fiber unilayer specimens, each containing thirty-one approximately equally spaced fibers (S-glass, 0.00485-in. diameter) were prepared and tested in an Instron machine at three strain rates (0.0265 in./in./min, 0.66 in./in./min and 26.5 in./in./ min). Grid lines were placed on composite specimen producing interference moiré fringes with a reference master grid placed in front of the specimen. The specimens were observed photographically during deformation. The experimental bundle strength compares well with that obtained on the basis of Daniels' theory. The experimental standard deviation is, however, much larger than that predicted theoretically. The experimental mean composite strength is compatible with that obtained on the basis of rule of mixtures and Gücer-Gurland models. The Zweben crack-propagation criterion [E 2(f C )=1] gives too low a value for the composite strength. A new criterion [E 3(fC)=1] is suggested for the present test series. Due to the rather large standard deviation and the small number of test samples it was not possible to quantitatively evaluate the effect of rate of straining. However, it is observed that, within the range of strain rates employed, the effect of strain rate on bundle and composite strengths does not exceed 20 percent and 10 percent, respectively.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

Abbreviations

d f :

fiber diameter

E i :

groups containingi fiber breaks (i=1, 2, 3…)

E f :

Young's modulus for the fibers

E m :

Young's modulus for the matrix

E L (f):

expected strength of fibers of lengthL

f :

stress

f B :

bundle strength (load/fiber cross-section area)

f c :

composite strength (load/fiber cross-section area)

G m :

shear modulus of the matrix

L :

specimen length

n :

number of slabs (L/δ)

N :

number of fibers

v :

Instron head speed

V f :

fiber volume fraction

V m :

matrix volume fraction

α,β:

Weibull distribution parameters

δ:

ineffective length (length that carries less than 90 percent of the fiber load)

\(\dot \varepsilon\) :

strain rate

ψ:

bundle standard deviation

\(\psi _C\) :

composite standard deviation

References

  1. Dow, N. F., Rosen, B. W. andHashin, Zvi, “Studies of Mechanics of Filamentary Composites,”Space Sciences Laboratory, Missile and Space Division, General Electric Company, Philadelphia, Pa. (Dec. 1965).

    Google Scholar 

  2. Materials Advisory Board Ad Hoc Committee on Micromechanics of Fibrous Composites, “Micromechanics of Fibrous Composites,”National Academy of Sciences-National Research Council, Washington, D. C. (May 1965).

    Google Scholar 

  3. Kelly, A. and Davies, G. J., “The Principles of Fiber Reinforcement of Metals,” Metallurgical Reviews,10, (37), (1965).

  4. Tyson, W. R. andDavies, G. J., “A Photoelastic Study of the Shear Stresses Associated with the Transfer of Stress During Fiber Reinforcement,”Brit. Jnl. Appl. Phys.,16,199–205 (1965).

    Google Scholar 

  5. Schuster, D. M. andScala, E., “The Mechanical Interaction of Sapphire Whiskers with a Birefringent Matrix,”Trans. AIME,230,1635–1640 (1964).

    Google Scholar 

  6. MacLaughlin, T. F., “Effect of Fiber Geometry on Stress in Fiber-reinforced Composite Materials,”Experimental Mechanics,6,481–492 (1966).

    Article  Google Scholar 

  7. MacLaughlin, T. F., “A Photoelastic Analysis of Fiber Discontinuities in Composite Materials,”Jnl. of Composite Materials,2,44–55 (1968).

    Google Scholar 

  8. Edelman, W. E. and Dahlke, H. J., “Photomechanics of Stresstransfer Mechanism in Composite Materials,” 1967 SESA Annual Meeting, Chicago, Ill., Oct. 31–Nov. 3.

  9. Jenkins, D. R., “Analysis of Behavior Near a Cylindrical Glass Inclusion by Scattered Light Photoelasticity,” Owens-Corning Fiberglass Co.

  10. Ebullin, J., Berry, J. W. and Gatti, A., “Some Fundamental Fracture Mechanisms Applicable to Advanced Filament Reinforced Composites,” Space Sciences Laboratory, Materials Section, General Electric Co., Missile Space Div.

  11. Pih, D. and Sutliff, D. R., “Photoelastic Analyses of Reinforced Composites,” AFML-TR-68-380 (Nov. 1968).

  12. Rosen, B. W., “Mechanics of Composite Strengthening, Fiber Composite Materials,” Am. Soc. Metals (1965).

  13. Zweben, C., “Tensile Failure Analysis of Fibrous Composites,”AIAA Jnl.,6 (12),2325–2331 (1968).

    Google Scholar 

  14. Boue, C. A., “Microscopic Study of Mode of Fracture in Filament Wound Glass Resin Composites,”T. & A. M. Report No. 234, Univ. of Ill. (Urbana), (Nov. 1962).

    Google Scholar 

  15. Grinius, V. G., “Micromechanics-Failure Mechanism Studies,” Technical Report AFML-TR-66-177, Air Force Materials Laboratory (Aug. 1968).

  16. Friedman, E., Flom, D. G. and Mazzio, V. F., “High Strength, High Modulus Whisker Reinforced Plastic Composites,” Technical Report AFML-TR-66-362, Air Force Materials Laboratory (Feb. 1967).

  17. Jech, R. W., McDaniels, D. L. and Weston, J. W., “Fiber Reinforced Metallic Composites,” Proc. Sixth Sagamore Ordnance Materials Research Conf. (Aug. 1959).

  18. Parratt, N. J., “Defects in Glass Fibers and Their Effect on the Strength of Plastic Mouldings,” Rubber Plastics,41, (263) (1960).

  19. Coleman, B. D., “A Stochastic Process Model for Mechanical Breakdown,”Trans. Soc. of Rheology,1,153–168 (1957).

    Google Scholar 

  20. Gücer, D., Gurland, J., “Comparison of the Statistics of Two Fracture Modes,”Jnl. Mech. Phys. Solids,10,365–373 (1962).

    Google Scholar 

  21. Zweben, C. and Rosen, B. W., “A Statistical Theory of Material Strength with Application to Composite Materials,” AIAA Paper No. 69-123, Presented at AIAA 7th Aerospace Sciences Meeting, New York, Jan. 20–22, 1969.

  22. McKee, R. B. Jr., and Sines, G., “A Statistical Model for the Tensile Fracture of Parallel Fiber Composites,” ASME Paper No. 68-WAIRP-7, Presented at ASME Winter Annual Meeting, New York, Dec. 1–5, 1968.

  23. Daniels, H., “The Statistical Theory of the Strength of Bundles of Threads 1,”Proc. Royal Society,183A,405–435 (1945).

    MathSciNet  Google Scholar 

  24. Armenàkas, A. E., Garg, S. K. andSciammarella, C. A., “Strength Characteristics of Glass Fibers Under Dynamic Loading,”Jnl. of Appl. Phys.,41 (4),1657–1664 (March 1970).

    Google Scholar 

  25. Coleman, B. D., “On the Strength of Classical Fibers and Fiber Bundles,”Jnl. Mech. Phys. Solids,7,60–70 (1958).

    MATH  Google Scholar 

  26. Epstein, B., “Statistical Aspects of Fracture Problems,”Jnl. Appl. Phys.,19,140–147 (1948).

    Google Scholar 

  27. Hedgepeth, J., “Stress Concentrations in Filamentary Structures,” NASA TN D-882 (May 1961).

Download references

Authors
  1. A. E. Armenakas
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. S. K. Garg
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. C. A. Sciammarella
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. V. Svalbonas
    View author publications

    You can also search for this author in PubMed Google Scholar

Additional information

A. E. Armenakas, S. K. Garg, C. A. Sciammarella and V. Svalbonas were associated with Polytechnic Institute of Brooklyn at the time that paper was prepared.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Armenakas, A.E., Garg, S.K., Sciammarella, C.A. et al. Experimental study of the failure mechanism and strength characteristics of fiber bundles and composites. Experimental Mechanics 12, 1–10 (1972). https://doi.org/10.1007/BF02320783

Download citation

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF02320783

Keywords

Search

Navigation