VISCOELASTIC BEHAVIOR OF A NONLINEAR FIBER-REINFORCED PLASTIC.

Abstract

The nonlinear mechanical properties of a unidirectional, glass fiber-epoxy composite at 164F are characterized by using creep and recovery tests together with a constitutive equation based on a thermodynamic theory. The results show that the composite is linearly elastic for the load range studied, but nonlinear viscoelastic behavior is observed for the other orientations. Guided by the nonlinear constitutive equation, the creep and recovery data are plotted on double-logarithmic paper, and the material properties are found by shifting the data to form a 'master curve' for each fiber orientation. Four principal creep compliances are estimated by using the master curves and tensor transformation relations. Finally, we use the nonlinear equation to predict strain response due to multiple-step loading and unloading. The Appendix contains two abstracts of papers which were completed and published during the period covered by this report. (Author)

Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1969
Accession Number
AD0693654

Entities

People

  • R. A. Schapery
  • Yuequn Lou

Organizations

  • Purdue University

Tags

DTIC Thesaurus Topics

  • Composite Materials
  • Constitutive Equations
  • Epoxy Composites
  • Equations
  • Fibers
  • Glass Fibers
  • Materials
  • Mechanical Properties
  • Orientation (Direction)
  • Recovery
  • Textiles
  • Unidirectional

Readers

  • Calculus or Mathematical Analysis
  • Mechanical Engineering/Mechanics of Materials.
  • Reinforced Composite Materials