A Plate Impact Experiment for Studying Crack Initiation at Loading Rates K(I) Approximately 10(8) MPa m/s,

Abstract

A symmetric plate impact technique is being developed for establishing the critical conditions for dynamic fracture initiation at extremely high loading rates. The specimen consists of a circular disc with a mid-plane, prefatigued, edge crack that has propagated halfway across the diameter. A compressive pulse propagates through the specimen, reflects from the rear surface, and subjects the crack plane to a step tensile pulse. The motion of the rear surface of the specimen is monitored with a laser interferometer system in order to determine the loading time required for crack extension to begin. Using this time in the elastodynamics solution of the stress wave diffraction problem, one can obtain the critical value of the stress intensity factor for dynamic fracture initiation. Preliminary experiments are being conducted on SAE 4340 VAR steel.

Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1983
Accession Number
ADP003103

Entities

People

  • G. Ravichandran
  • R. J. Clifton

Organizations

  • Brown University

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • California
  • Diameters
  • Diffraction
  • Intensity
  • Interferometers
  • Physical Properties
  • Stress Intensity Factors
  • Stress Waves
  • Stresses
  • Waves
  • Workshops

Fields of Study

  • Physics

Readers

  • Materials Science (Mechanical Engineering).
  • Structural Health Monitoring of Composite Structures.

Technology Areas

  • Directed Energy