Dynamic Measurement of the J Integral in Ductile Metals: Comparison of Experimental and Numerical Techniques

Abstract

For two-dimensional, monotonically loaded, stationary cracks, the J integral, defined by Rice is a path independent line integral over an open contour surrounding the crack tip, and its value is a measure of the intensity of the crack tip strain singularity. The critical value of J for crack initiation is commonly used as a measure of fracture toughness in ductile materials. For three dimensional plates of uniform thickness containing through cracks, the J integral is defined over a cylindrical surface surrounding the entire crack front. For monotonic loading or for materials obeying the deformation theory of plasticity, the value of this integral is independent of the choice of surface. In addition, for materials obeying the deformation theory of plasticity this integral may be interpreted as the energy release rate for self-similar crack extension along the entire crack front. A per thickness value, denoted in the rest of the paper as J, can be obtained by dividing the above surface integral by the thickness of the plate.

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Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1988
Accession Number
ADA243568

Entities

People

  • Alan T. Zehnder
  • Ares J. Rosakis
  • Sridhar Krishnaswamy

Organizations

  • California Institute of Technology

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Boundaries
  • Cameras
  • Caustics
  • Crack Tips
  • Diameters
  • Finite Element Analysis
  • Fracture (Mechanics)
  • Geometry
  • High Speed Cameras
  • J Integrals
  • Materials
  • Measurement
  • Mechanics
  • Numerical Analysis
  • Photographs
  • Three Dimensional
  • Two Dimensional

Readers

  • Fluid Dynamics.
  • Materials Science (Mechanical Engineering).