A MECHANISM FOR THE CONTROL OF CRACK PROPAGATION IN ALL-BRITTLE SYSTEMS,

Abstract

The stress distribution close to the tip of a crack which has a finite tip radius and which is being opened either by means of a remotely applied tension field sigma sub(y,0) or by means of a concentrated force (e.g. a wedge driven into the crack) has been computed. It is shown that there exist tensile stresses sigma sub x parallel to the plane of the crack and ahead of the crack tip. The maximum value of the tension sigma sub x is an approximately constant fraction about 1/5 of the peak stress concentration sigma sub(y, max) which usually causes crack propagation. Inside a brittle solid, if a plane of weakness or potential cleavage is present and is roughly normal to the plane of the original crack, this interface may break and produce a secondary crack in such a manner as to interfere with the progress of the primary crack. If the ratio of the adhesive strength of the interface to the general cohesive strength of the solid is in the right range large increases in the strength and toughness of otherwise brittle solids may result. (Author)

Document Details

Document Type
Technical Report
Publication Date
Mar 19, 1964
Accession Number
AD0619199

Entities

People

  • J. Cook
  • J. E. Gordon

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Adhesives
  • Crack Propagation
  • Crack Tips
  • Cracks
  • Mechanical Properties
  • Stress Concentration
  • Stresses
  • Tensile Stress

Readers

  • Materials Science (Mechanical Engineering).
  • Systems Analysis and Design