Metallurgical Transactions

, Volume 1, Issue 9, pp 2573–2581 | Cite as

The effect of microstructure on the stress-corrosion susceptibility of a high purity Al−Zn−Mg alloy in a NaCl solution

  • A. J. de Ardo
  • R. D. Townsend
Environmental Interactions


The effect of microstructure on the susceptibility of a high purity Al-6.8 pct Zn-2.3 pct Mg Alloy to stress-corrosion cracking in an aqueous salt solution (3.5 wt pct NaCl) has been studied. The results of testing a series of specimens having controlled microstructures and the same yield strength of 40,000 psi indicate that the susceptibility to stress-corrosion is controlled by the type, size, and spacing of the matrix precipitate through the effect of these precipitates on the deformation process. Although the width of the precipitate free zone appears to have no effect on susceptibility, the grain boundary precipitate seems to influence susceptibility in certain cases. Supporting evidence for these observations has been obtained by light and electron microscopic examinations of both deformed and undeformed specimens. A model is proposed which explains many experimental observations.


Heat Treatment Aging Time Slip Band Metallurgical Transaction Volume Precipitate Free Zone 
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Copyright information

© The Minerals, Metals & Materials Society - ASM International - The Materials Information Society 1970

Authors and Affiliations

  • A. J. de Ardo
    • 1
  • R. D. Townsend
    • 2
  1. 1.Department of Metallurgy and Materials ScienceCarnegie-Mellon UniversityPittsburgh
  2. 2.with Central Electric Generating Board Research LaboratoriesLeatherheadEngland

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