The Effects of Corrosion and Cathodic Charging on Fatigue Crack Propagation in 7075-T651 Aluminum.

Abstract

Corrosion fatigue crack propagation tests were performed on 7075 aluminum in dry argon, and solutions of NaCl and Na2SO4 under free corrosion conditions and under applied polarization. Bulk solution pH and oxygen level were also varied. Tests were also conducted in air after pre-exposure to an aggressive environment. Results indicate that both aqueous solutions appreciably increase fatigue crack growth rates. The Cl-ion generally produces the greatest increase in fatigue crack growth rate. Results indicate that adjusting bulk solution pH and decreasing the oxygen level can accelerate fatigue cracking. The magnitude of these effects is a function of the electrochemical conditions and the integrity of the oxide film at the crack tip.

Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1978
Accession Number
ADA059315

Entities

People

  • David J. Duquette
  • Stephen E. Lebeau

Organizations

  • Rensselaer Polytechnic Institute

Tags

DTIC Thesaurus Topics

  • Aluminum
  • Aqueous Solutions
  • Corrosion
  • Crack Propagation
  • Crack Tips
  • Cracking (Fracturing)
  • Cracks
  • Environment
  • Fatigue Cracking
  • Films
  • Material Degradation Processes
  • Materials
  • Oxide Films
  • Oxides
  • Polarization

Fields of Study

  • Materials science

Readers

  • Circadian Sleep-Wake Regulation and Chronobiology
  • Pulsed Power and Plasma Physics.
  • Surface Engineering/Surface Coating Technology.