An Experimental Study to Determine the Reduction in Ultimate Bending Moment of a Composite Plate due to an Internal Delamination.

Abstract

The purpose of this study was to determine experimentally the effects of internal delaminations in a graphite-epoxy composite plate on the plate's ultimate bending moment. The experiments were conducted using 4-inch by 7-inch specimens with a balanced 0, + or - 45, 90, 8-ply layup. The delaminations were created by inserting a thin teflon disc between two lamina during layup preparation. The location of the disc, i.e. delamination, was varied in each test, and two disc sizes were considered. The test results revealed that delaminations located near an outer surface resulted in a greater reduction in the ultimate moment than those located near the center of the layup. Furthermore, the reduction in ultimate bending moment was found to be independent of the disc size. The tendency for the internal delaminations to propagate at relatively low load levels was observed and recorded. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1977
Accession Number
ADA052662

Entities

People

  • Robert Gary Sprigg

Organizations

  • Naval Postgraduate School

Tags

Communities of Interest

  • Air Platforms
  • Weapons Technologies

DTIC Thesaurus Topics

  • Aircrafts
  • Bending Moments
  • Composite Materials
  • Delamination
  • Diameters
  • Epoxy Composites
  • Graphite Epoxy Composites
  • Graphitic Materials
  • Horizontal Stabilizers
  • Laminates
  • Materials
  • Materials Laboratories
  • Materials Science
  • Materials Testing
  • Military Aircraft
  • Physical Properties
  • United States Naval Academy

Readers

  • Structural Health Monitoring of Composite Structures.