The Delayed Fracture of Aluminum Alloys.

Abstract

The stress corrosion cracking (SCC) of high purity Al-Zn-Mg alloys has been studied in terms of the effects on SCC susceptibility of: bulk chemistry, bulk microstructure, oxide film chemistry, and oxide film morphology. For alloys having equivalent solute content (wt. % Zn + wt. % Mg), higher bulk concentrations of magnesium lead to slightly increased susceptibility in acetic-acid-brine solution. Interrupted quenching failed to produce a microstructure exhibiting reduced SCC susceptibility. Preliminary results indicate that an oxide stripping procedure, that removes the magnesium-rich oxide film formed during heat treating, and replaces it with an amorphous alumina film, decreases SCC susceptibility. Porosity in the original castings caused data to be scattered, so new porosity-free materials have been acquired and the oxide film studies will be repeated. (Author)

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Document Details

Document Type
Technical Report
Publication Date
May 01, 1980
Accession Number
ADA085137

Entities

People

  • Dave Venables
  • John A. S. Green
  • Joseph R. Pickens

Organizations

  • Martin Marietta

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Aluminum Alloys
  • Auger Electron Spectroscopy
  • Auger Electrons
  • Chemistry
  • Corrosion
  • Cracks
  • Diagrams
  • Electron Microscopes
  • Electron Microscopy
  • Electron Spectroscopy
  • Electrons
  • Grain Boundaries
  • Materials
  • Oxide Films
  • Spectroscopy
  • Stress Corrosion
  • Stress Corrosion Cracking

Fields of Study

  • Materials science

Readers

  • Materials Science and Engineering.
  • Metallurgy
  • Surface Coatings Technology.