Causes of Delamination Failures of Kevlar/Epoxy Laminates Used in Hardened Army Tactical Shelters

Abstract

A series of chemical, mechanical, and physical tests were performed on Kevlar/epoxy laminates to determine the cause of failure in a structure which had undergone extensive delamination during a simulated solar load test. The results of these tests indicated that improper fabrication procedures caused microcracking at the fiber matrix interface which made the material particularly susceptible to invasion by environmental moisture and subsequent delamination at elevated temperatures. The material was also found to have been undercured by approximately 30%. Acting on recommendations resulting from this study, the fabricator was able to eliminate the microcracking and significantly increase the degree of cure in the laminates. Preliminary measurements of the effect of moisture on the mechanical properties of the laminate suggested that design properties of the material should be determined at elevated temperature and humidity.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1985
Accession Number
ADA165507

Entities

People

  • Margaret E. Roylance
  • William W. Houghton

Tags

Communities of Interest

  • Advanced Electronics
  • Air Platforms
  • Human Systems
  • Space
  • Weapons Technologies

DTIC Thesaurus Topics

  • Air Force
  • Chemistry
  • Composite Materials
  • Delamination
  • Epoxy Laminates
  • Epoxy Resins
  • Fabrication
  • Laminates
  • Liquid Chromatography
  • Material Degradation Processes
  • Materials
  • Materials Laboratories
  • Materials Processing
  • Materials Science
  • Mechanical Properties
  • Military Research
  • Resonant Frequency

Readers

  • Reinforced Composite Materials