BEHAVIOR OF PLASTICS UNDER IMPULSIVE STRESS

Abstract

Under brief impulsive loading by flying plates, fractures formed in rubbery resins differ from those formed in glassy resins. The latter usually crack by spreading of well-defined ridged disks roughly parallel to the wave front. Fractures in rubbery resins may be bursts of feathery cracks, ridged cones, or nearly feature less disks. The fracture orientation usually departs widely from that of the wave front. The fracture threshold for a glassy resin was found to lie between 0.4 and 0.6 kb; whereas the threshold for a chemically similar rubbery resin lay between 1.0 and 1.4 kb. Changes of pulse height and pulse shape with travel were found to be rapid within the first pulse length but quite slow thereafter. Pulse steepness was shown to be lost faster in rubbery than in glassy material. The observations were made with quartz transducers. Electron and optical micro graphy of fracture surfaces, x-ray diffraction, and measurements of Poisson's ratio and compressibility under dynamic conditions all contributed to an explanation of differences in strength and type of fractures.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1963
Accession Number
AD0426664

Entities

People

  • And H. W. Semon
  • D. G. Flom
  • F. A. Lucy

Organizations

  • General Electric

Tags

Communities of Interest

  • Advanced Electronics
  • Air Platforms
  • Weapons Technologies

DTIC Thesaurus Topics

  • Air Force
  • Cameras
  • Diffraction
  • Geometry
  • Light Sources
  • Materials
  • Measurement
  • Mechanical Properties
  • Orientation (Direction)
  • Photographs
  • Plastics
  • Scattering
  • Stress Concentration
  • Three Dimensional
  • Transducers
  • X Rays
  • X-Ray Diffraction

Fields of Study

  • Geology

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Materials Science (Mechanical Engineering).
  • Materials Science and Engineering.

Technology Areas

  • Microelectronics