Deformation, Fracture and Explosive Properties of Reactive Materials

Abstract

A range of optical techniques, based on moire and speckle, have been developed at Cambridge for studies of the deformation, strength and fracture properties of materials including PBXs and propellants. In some cases, these high spatially sensitive methods (micron resolution) have been combined with high speed photographs (microsecond timing intervals). A review paper has been prepared for the 10th Detonation Symposium and this is given as Appendix 1. Section 2 describes a study of the deformation of inert propellant grains; cylinders with seven axial holes. The grains were stressed to failure in three geometries. The optical technique chosen for the study was the 'fine grid method. An important advance was the development of methods to add a fine grain grid to the surface of the grains (spatial period - 80 micron). The results show the detailed deformation, for the whole viewed surface, up to failure. Section 3 is concerned with fragment attack of propellant grains. A gas gun has been used to fire projectiles of various shapes into different arrays and types of propellant grains; the whole process is recorded with an image converter camera at microsecond framing intervals. The results show the way the propellant deforms and the sites at which any ignition takes place. This report presents results on uncased propellant. Appendix 2, a preprint of a paper presented at the 10th Detonation Symposium, gives results on cased propellant. Finally, section 4 gives recent results obtained with our transparent anvil drop-weight apparatus. Explosive, Ignition, Impact, Sensitivity, Hot spots, High speed photography, Optical techniques, Deformation fracture, PBX's Propellant.

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1993
Accession Number
ADA269999

Entities

People

  • John E. Field

Organizations

  • University of Cambridge

Tags

Communities of Interest

  • Weapons Technologies

DTIC Thesaurus Topics

  • Cameras
  • Combustion
  • Explosive Charges
  • Explosives
  • Geometry
  • Image Converters
  • Insensitive Explosives
  • Materials Laboratories
  • Measurement
  • Mechanics
  • Microsecond Time
  • Photographs
  • Photography
  • Plastic Bonded Explosives
  • Propellant Grains
  • Propellants
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Geodesy
  • Mechanical Engineering/Mechanics of Materials.
  • Rocket Propulsion.