Wave Surfaces Due to Impact on Anisotropic Fiber Composite Plates.

Abstract

The application of advanced fiber composite materials to the fabrication of fan or compressor blades depends on their ability to sustain limited damage under impact forces. For small objects such as pebbles or hailstones, the impact times are of the order of microseconds. Thus the energy transmission to the blade is completed before there are any or many reflections from the boundaries. The stress waves induced in anisotropic plates by transverse, short-duration impact forces are examined in this report. The anisotropy is related to the layup angles of the fibers. Using a modification of Mindlin's approximate theory of plates, it is shown that both extensional and bending waves are generated by transverse impact. The magnitudes of the wave velocities in different directions are calculated for graphite fiber-epoxy matrix plates as well as boron-aluminum and glass-epoxy systems for various layup angles. Finally the shapes of the wave fronts or wave surfaces due to point impact are also presented for the cases mentioned.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1971
Accession Number
ADA308173

Entities

People

  • Francis C. Moon

Organizations

  • Glenn Research Center

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Composite Materials
  • Compressor Blades
  • Elastic Waves
  • Epoxy Composites
  • Equations
  • Equations Of Motion
  • Failure Mode And Effect Analysis
  • Glass Fibers
  • Graphitic Materials
  • Impact Point
  • Materials
  • Materials Processing
  • Plane Waves
  • Secondary Waves
  • Stress Waves
  • Wave Propagation
  • Waves

Fields of Study

  • Physics

Readers

  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Structural Dynamics.
  • Structural Health Monitoring of Composite Structures.