CRACK INITIATION IN METALLIC MATERIALS.

Abstract

The mechanisms of crack initiation in LiF single crystals have been studied in Phase I and a value for Neuber's finite particle size has been determined. A dislocation reaction has been proposed to account for the etch pit patterns observed at the crack tips in the LiF crystals and the strain energy obtained from this model has been compared to the strain energy obtained from continuum elasticity considerations. In Phase II, calibration of the fatigue fixture used in the experimental program has been completed and crack growth studies in fatigue specimens of AISI 301 stainless steel are under way. Studies of the stress variation due to relaxation and change in the load carrying cross sectional area in the specimen caused by the presence of the crack are also in progress. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jul 01, 1964
Accession Number
AD0603785

Entities

People

  • G. Nash
  • K. Schroder
  • P. Packman
  • V. Weiss

Organizations

  • Syracuse University

Tags

DTIC Thesaurus Topics

  • Calibration
  • Crack Tips
  • Cracks
  • Crystals
  • Dislocations
  • Elastic Properties
  • Materials
  • Particle Size
  • Particles
  • Single Crystals
  • Stainless Steel
  • Steel

Fields of Study

  • Materials science

Readers

  • Materials Science and Engineering.
  • Structural Health Monitoring of Composite Structures.