The Feasibility of a Shear-Compression Kolsky Bar with Simultaneous Wave Arrival at the Sample

Abstract

Improving armor materials requires a full understanding of the constitutive response of a material subjected to a multiaxial stress state at dynamic strain rates. This has proved almost impossible to measure dynamically. This report assesses the feasibility of one method to produce an axial wave and a shear wave that arrive at a sample simultaneously. The method uses a modified Kolsky bar apparatus with a pair of gun barrels, where one projectile creates an axial wave and the other a shear wave in the Kolsky bars. The waves are created at opposite ends of the apparatus and travel toward the sample from opposite directions. The time difference created by sending the signals to the valves, the opening of the valves, and the time the projectile spends moving down the gun barrel needs to be consistent enough to be corrected for, since the waves travel at different velocities. The model system built shows the error is too large and, thus, this method is not feasible.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 2020
Accession Number
AD1090128

Entities

People

  • Christopher S. Meredith

Tags

DTIC Thesaurus Topics

  • Compression
  • Compression Waves
  • Gas Guns
  • Gun Barrels
  • Guns
  • Hydraulic Cylinders
  • Laser Beams
  • Materials
  • Microsecond Time
  • Projectiles
  • Secondary Waves
  • Shear Stresses
  • Strain Rate
  • Three Dimensional
  • Waves
  • Weapons

Fields of Study

  • Physics

Readers

  • Educational Psychology
  • Mechanical Engineering/Mechanics of Materials.
  • ballistics.