NOTCH BEHAVIOR IN METALS.

Abstract

Measurements of the shape and size of the plastic zone, delineating the transverse strain field and the corresponding crack-tip displacements as a function of stress level, under on-load conditions are described. The measurements were done on notched sheet coupons of 4330-M steel and 2219-T87 and 7075-T6 aluminum, with the aid of a replicating technique. The extent of the plastic zone and internal cracking is shown to be connected. In this way, the progress of slow crack growth in the interior of the sheets is reconstructed. A correlation of the experimental values of crack-tip displacements with the prediction of the DM model (Dugdale-Muskhelishvili), in the presence of a slowly growing internal crack, is noted and discussed. The analysis of the DM model is extended to the case of a crack in a plate of finite width and is solved numerically, using a point-matching technique. The calculations show that in the case of a plate containing a crack one-sixth of the plate width, loaded to one-half of the yield stress, the plastic zone size for finite-plate analysis was 3 percent higher over the corresponding size for infinite (DM) plate analysis. When the crack length was one-half of the plate width and the load was one-third of the yield stress, the finite-plate analysis gave a plastic zone size that was approximately twice the value given by infinite-plate analysis. (Author)

Document Details

Document Type
Technical Report
Publication Date
May 31, 1966
Accession Number
AD0801536

Entities

People

  • A. R. Rosenfield
  • Arunabh Mukherjee
  • G. T. Hahn
  • L. E. Hulbert

Organizations

  • Battelle Memorial Institute

Tags

DTIC Thesaurus Topics

  • Aluminum
  • Crack Tips
  • Cracks
  • Displacement
  • Measurement
  • Metals
  • Transverse

Fields of Study

  • Engineering

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Metallurgy