Mechanical characterization of IM7/8551-7 carbon/epoxy under biaxial stress: (Final report)

Colvin, Jr, G E; Swanson, S R

Title: Mechanical characterization of IM7/8551-7 carbon/epoxy under biaxial stress: (Final report)

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Abstract

This is the final report on an investigation to evaluate the mechanical response of Hercules IM7/8551-7 carbon/epoxy, which is a high strength, high elongation fiber and a high toughness resin system used in a prepreg form. The material characterization involved testing both laminate and lamina forms under a wide range of biaxial stress states. Tubular specimens were employed that have been designed to eliminate undesirable end effects, permitting uniform stress states to be achieved. Quasi-isotropic (90/+-45/0)/sub ns/laminates and (90)/sub 16T/ lamina specimens were loaded under combinations of internal pressure, axial load, and torsion. Both stiffness and strength data were obtained under these multiaxial stress conditions. The measured laminate stiffnesses correlated well using classical laminated plate theory, and that laminate failure occurred in the two separate modes of matrix cracking and fiber failure. Like the previously examined carbon/epoxy systems, laminate failure could be predicted by using a fiber failure criterion to identify the critical plies and critical load levels. It was found that either maximum fiber stress or fiber direction strain could be used as a failure criterion on a ply level. 16 refs., 10 figs., 3 tabs.

Authors:: Colvin, Jr, G E; Swanson, S R

Publication Date:: Fri Nov 13 00:00:00 EST 1987

Research Org.:: Utah Univ., Salt Lake City (USA). Dept. of Mechanical Engineering

OSTI Identifier:: 5613415

Report Number(s):: UCRL-15977
ON: DE88004058

DOE Contract Number:: W-7405-ENG-48

Resource Type:: Technical Report

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; COMPOSITE MATERIALS; MECHANICAL PROPERTIES; CARBON COMPOUNDS; COMPRESSIBILITY; CRACKS; EPOXIDES; FAILURES; FIBERS; LAYERS; MATERIALS TESTING; PROGRESS REPORT; RESINS; SHEAR; STRESSES; TUBES; DOCUMENT TYPES; MATERIALS; ORGANIC COMPOUNDS; ORGANIC OXYGEN COMPOUNDS; ORGANIC POLYMERS; PETROCHEMICALS; PETROLEUM PRODUCTS; POLYMERS; TESTING; 360603* - Materials- Properties

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                    Colvin, Jr, G E, and Swanson, S R. Mechanical characterization of IM7/8551-7 carbon/epoxy under biaxial stress: (Final report).  United States: N. p., 1987. 
        Web.

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                    Colvin, Jr, G E, & Swanson, S R. Mechanical characterization of IM7/8551-7 carbon/epoxy under biaxial stress: (Final report).  United States.

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                    Colvin, Jr, G E, and Swanson, S R. 1987.  
        "Mechanical characterization of IM7/8551-7 carbon/epoxy under biaxial stress: (Final report)".  United States.

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@article{osti_5613415,

  title        = {Mechanical characterization of IM7/8551-7 carbon/epoxy under biaxial stress: (Final report)},

  author       = {Colvin, Jr, G E and Swanson, S R},

  abstractNote = {This is the final report on an investigation to evaluate the mechanical response of Hercules IM7/8551-7 carbon/epoxy, which is a high strength, high elongation fiber and a high toughness resin system used in a prepreg form. The material characterization involved testing both laminate and lamina forms under a wide range of biaxial stress states. Tubular specimens were employed that have been designed to eliminate undesirable end effects, permitting uniform stress states to be achieved. Quasi-isotropic (90/+-45/0)/sub ns/laminates and (90)/sub 16T/ lamina specimens were loaded under combinations of internal pressure, axial load, and torsion. Both stiffness and strength data were obtained under these multiaxial stress conditions. The measured laminate stiffnesses correlated well using classical laminated plate theory, and that laminate failure occurred in the two separate modes of matrix cracking and fiber failure. Like the previously examined carbon/epoxy systems, laminate failure could be predicted by using a fiber failure criterion to identify the critical plies and critical load levels. It was found that either maximum fiber stress or fiber direction strain could be used as a failure criterion on a ply level. 16 refs., 10 figs., 3 tabs.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/5613415},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Fri Nov 13 00:00:00 EST 1987},

  month        = {Fri Nov 13 00:00:00 EST 1987}

}

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