Non-Destructive Evaluation of Adhesive Bonded Structures Using Dielectric Methods

Abstract

This report results from a contract tasking University of Strathclyde as follows: The contractor shall characterize the dielectric signature of the hydrated lightly coated oxide surface, and investigate the effect of various solvent systems on bond durability. The contractor shall carry out aging studies using hydraulic fluid, aviation fluid, de-icing fluid and urea solutions to explore the way in which aging is influenced by these media. The outcome of this study shall be a definition of the rate and potential mechanisms of attack of these common fluids. The contractor shall characterize the aging of boron fiber/epoxy aluminum bonded structures taking into account that the electrical conductivity of the boron fibers is intermediate between those of carbon and glass. As a result the approach to measurements used with either the carbon fibers or the aluminum structures is not appropriate with these structures. An electrode structure has been constructed which allows investigation of the dielectric properties of these structures, but the effects of moisture and aging in high humidity environments has not been evaluated. Structures have been created and it is planned to carry out aging studies over the next two years. Boron fiber composites are used in repair of damage on the skins of aluminum fabricated aircraft. This study will demonstrate the usefulness of the method for the characterization of aging in these bonded structures.

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Document Details

Document Type
Technical Report
Publication Date
Aug 01, 2002
Accession Number
ADA408347

Entities

People

  • Richard Pethrick

Organizations

  • University of Strathclyde

Tags

Communities of Interest

  • Advanced Electronics

DTIC Thesaurus Topics

  • Adhesives
  • Aluminum
  • Bonded Joints
  • Carbon Fibers
  • Composite Materials
  • Contractors
  • Contracts
  • Dielectric Permittivity
  • Dielectric Properties
  • Electrical Conductivity
  • Environment
  • Fibers
  • Fluids
  • High Humidity
  • Hydraulic Fluids
  • Mechanical Properties
  • Test And Evaluation

Readers

  • Aerospace Test and Evaluation
  • Computational Fluid Dynamics (CFD)
  • Reinforced Composite Materials