Crack Propagation in Z5U Multilayer Dielectrics.

Abstract

It has been found that moisture has a deleterious effect in enhancing slow crack growth in Z5U multilayer ceramics similar to the effect shown in other ceramic materials. The enhancement of slow crack growth in the presence of moisture has been demonstrated for both parallel and perpendicular orientations of the multilayer structure with respect to the propagating crack. The application of DC electric fields to the multilayer ceramics either has no effect or serves to retard crack propagation depending upon the crack orientation with respect to the applied electric field. The fracture toughness or critical stress intensity factor as measured by the double torsion testing technique has been found to vary with respect to orientation of the multilayer structure. Higher fracture toughness values are obtained when the macroscopic crack is forced to propagate in a direction perpendicular to the multilayer structure.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
May 01, 1985
Accession Number
ADA159262

Entities

People

  • B. G. Koepke
  • K. D. Mchenry

Organizations

  • Honeywell International, Inc.

Tags

Communities of Interest

  • Advanced Electronics

DTIC Thesaurus Topics

  • Bodies
  • Ceramic Bodies
  • Ceramic Materials
  • Composite Materials
  • Crack Propagation
  • Cracks
  • Dielectrics
  • Electric Fields
  • Materials
  • Materials Processing
  • Mechanical Properties
  • Moisture
  • Orientation (Direction)
  • Parallel Orientation
  • Stress Intensity Factors
  • Stresses
  • Toughness

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Materials Science and Engineering.
  • Structural Health Monitoring of Composite Structures.