Gamma-Irradiation Damage in Age Hardening Al Alloys

Abstract

Pure Al and a series of age-hardenable Al alloys have been gamma- irradiated in a Co60 source at a dose of 6000 rads/min. Internal friction measurements have been made at 80 kHz by means of the Marx technique on samples in situ during irradiation. In Al and Al-3 w/o Cu, the damping decreases monotonically as is expected. The decrease is attributed to the immobilization of dislocations by the radiation-induced point defect pinners. In 2024-T6, 2017-T6 and A1-9.5 Mg, the damping passes through a minimum and begins an anomolous increase after 4 to 7 hours of irradiation. In the alloys which display the damping minimum, precipitate morphology changes during irradiation, with coarsening and/or de-coarsening and re-nucleation being observed. The effect appears to depend upon the presence of Mg. Theory predicts that morphology changes can occur during gamma-irradiation, with the mechanism being either Rutherford collision or Coulombic repulsion radiation damage.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Jul 01, 1974
Accession Number
AD0786578

Entities

People

  • Nicholas F. Fiore

Organizations

  • University of Notre Dame

Tags

Communities of Interest

  • Energy and Power Technologies
  • Weapons Technologies

DTIC Thesaurus Topics

  • Alloys
  • Charged Particles
  • Crystal Defects
  • Crystal Lattices
  • Crystal Structure
  • Dislocations
  • Electron Microscopy
  • Electrons
  • Energy
  • Engineering
  • Internal Friction
  • Literature Surveys
  • Materials
  • Materials Science
  • Point Defects
  • Precipitation
  • Radiation

Fields of Study

  • Physics

Readers

  • Materials Science and Engineering.
  • Nuclear and Radiation Engineering.
  • Powder metallurgy of Titanium alloys.