Fundamental Issues Regarding the High Temperature Failure Properties of Graphite/Polyimide Fabric Composites

Abstract

In this work, a method based on X-ray diffraction (XRD) measurements of internal stresses in embedded metallic ellipsoidal inclusions is briefly described. The method has been recently developed for the determination of residual thermal stresses in high temperature graphite/polyimide composites. The effects of external bending loads and aging on the measurements of the internal stress in unidirectional and woven graphite fiber (T650-3 5)/polyimide (PMR-15) composites were examined in addition to several other factors which could influence the accuracy of the stress measurements. Such factors as the volume fraction of inclusions, their aspect ratios and the interaction between individual embedded inclusions were also evaluated in this study. It has been show that despite its complexity the proposed method can be successfully applied to the evaluation of residual stresses in high temperature polymer matrix composites subjected to external loads and aging.

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Document Details

Document Type
Technical Report
Publication Date
Oct 01, 2004
Accession Number
ADA430088

Entities

People

  • M. S. Kumosa

Organizations

  • University of Denver

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Composite Materials
  • Crystal Structure
  • Elastic Properties
  • Failure Mode And Effect Analysis
  • Finite Element Analysis
  • Graphitic Materials
  • Materials Laboratories
  • Materials Processing
  • Materials Science
  • Materials Testing
  • Mechanical Properties
  • Mechanics
  • Plastic Properties
  • Polymer Matrix Composites
  • Stress Strain Relations
  • Stresses
  • Tensile Strength

Fields of Study

  • Materials science

Readers

  • Computational Modeling and Simulation
  • Mechanical Engineering/Mechanics of Materials.
  • Powder metallurgy of Titanium alloys.