Tensile Creep of CTD-101 S-2 Glass Reinforced Composites at 76 K

  • C. S. Hazelton
  • J. B. Darr
  • R. P. Reed
Part of the An International Cryogenic Materials Conference Publication book series (ACRE, volume 40)

Abstract

Laminates of epoxy fiberglass composite (C1D-101 epoxy, woven S-2 glass fabric, volume ~ 56%) were held under constant tensile stress at 76 K for up to 650 hours to measure creep response. Up to 5 specimens were simultaneously loaded under dead weight to various percentages (16% to 33%) of the ultimate tensile strength, and significant creep rates were detected. Two stages of creep were observed, an initial rapid stage, and a secondary, steady-state, creep stage. The tests were terminated before specimen failure occurred. Two equations (linear and power curve) were fit to the second stage data to predict creep behavior beyond the duration of the tests. Static tension tests were also performed to determine the baseline properties of the composite, which revealed transverse microcracking (90° to loading direction) at stresses as low as 22% of the ultimate strength. Therefore, creep behavior at stress levels above 22% is influenced by microcracking, crazing, and probably plastic and viscoelastic mechanisms.

Keywords

Ultimate Tensile Strength Creep Rate Ultimate Strength Creep Deformation Crack Density 
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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Copyright information

© Springer Science+Business Media New York 1994

Authors and Affiliations

  • C. S. Hazelton
    • 1
  • J. B. Darr
    • 1
  • R. P. Reed
    • 2
  1. 1.Composite Technology Development, Inc.BoulderUSA
  2. 2.Cryogenic Materials, Inc.BoulderUSA

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