OBSERVATIONS OF HYPERVELOCITY IMPACT OF TRANSPARENT PLASTIC TARGETS
Abstract
Targets of transparent plastic have been impacted with small projectiles at velocities up to 25,000 ft/sec. Photographs made at the rate of approximately 6 x 100000 frames per second show the projectile impact, luminous flash, crater formation, and shock waves in the target. Propagation of the waves and their reflections, and the fractures which they produce, are analyzed. Spalling near the rear surface of the target is seen as the shock is reflected as a tensile wave. Studies of impact of laminated targets show transmission and reflection of shock waves at each interface together with details of the complex fracture formation. These are also analyzed. A theory of fracture is presented which indicates that the fracture of Plexiglas or Lucite is time-dependent. The effects of the target's rear surface and the target temperature are discussed. It is shown that most of the effects of hypervelocity impact may be simulated by the use of explosives placed in small holes in the target face. This not only results in savings of both time and cost, but permits crater location with an accuracy that would be impossible to achieve by the use of a gun. These studies of transparent targets give a better insight into the nature of cratering and fracture by hypervelocity impact.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1964
- Accession Number
- AD0438947
Entities
People
- Ray Kinslow
Organizations
- Arnold Engineering Development Complex