The Effect of Loading on the Laser Ablation of Graphite/Epoxy Composite Material

Abstract

An investigation was conducted to quantify the effect structural loading of a graphite/epoxy member has upon the mass removal rate during laser ablation. An effective heat of ablation (Q*eff=energy absorbed/mass removed) was used as a measure of this efficiency. A simple physical model of the important factors affecting the graphite/simple physical model of the important factors affecting the graphite/epoxy was developed, and predictions were made of the effect of loading on Q*eff. A three-dimensional finite difference heat transfer code was written to predict the temperature distribution in the composite while modeling the orthotropic nature of the thermal conductivity tensor. The effect of thermal and mechanical loads upon the stress distribution in a single fiber was calculated. A hypothesis was formed that fracture of individual fibers, a process linearly dependent upon applied stress, will remove a fraction of the composite independent of the absorption of laser energy. Theses.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1989
Accession Number
ADA216209

Entities

People

  • Joseph L. Hamrick Ii

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies
  • Weapons Technologies

DTIC Thesaurus Topics

  • Classification
  • Composite Materials
  • Directed Energy Weapons
  • Epoxy Composites
  • Laser Beams
  • Materials Laboratories
  • Materials Processing
  • Materials Science
  • Materials Testing
  • Measurement
  • Mechanics
  • Photographs
  • Strain Gages
  • Temperature Gradients
  • Thermal Properties
  • Three Dimensional
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Computational Modeling and Simulation
  • Structural Health Monitoring of Composite Structures.
  • Thermal Physics or Thermal Science.

Technology Areas

  • Directed Energy