High-Speed Photographic Study of Wave Propagation and Impact Damage in Transparent Aluminum Oxynitride (AION)

Abstract

Fused silica and AlON (Aluminum Oxynitride) specimens were tested by means of a modified Edge-On Impact technique. The specimens were placed between crossed polarizers and the photo-elastic effect was utilized to visualize the stress waves. Pairs of impact tests at approximately equivalent velocities were carried out in transmitted plain (shadowgraphs, visualization of damage) and crossed polarized light (visualization of wave propagation). The experiments provided direct evidence of ceramic damage by nucleation and growth of fracture initiated by the stress waves, ahead of the coherent fracture front growing from the impacted edge. A comparison of the results in a reflected light set-up and the shadowgraphs indicated fracture nucleation in the interior of the ceramic. The experimental results provide a data basis for a deeper analysis of the damage mechanisms by means of numerical simulation.

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Document Details

Document Type
Technical Report
Publication Date
Feb 21, 2006
Accession Number
ADA454630

Entities

People

  • E. Strassburger

Tags

Communities of Interest

  • Weapons Technologies

DTIC Thesaurus Topics

  • Aluminum
  • Aluminum Oxides
  • Cameras
  • Impact Tests
  • Materials
  • Mechanical Properties
  • Nucleation
  • Optical Materials
  • Oxynitrides
  • Photographs
  • Polarizers
  • Refractive Index
  • Simulations
  • Stress Waves
  • Stresses
  • Wave Propagation
  • Waves

Readers

  • Combustion Dynamics and Shock Wave Physics.
  • Materials Science and Engineering.
  • Powder metallurgy of Titanium alloys.