Determination of Test Technique Influence on K sub ISCC Values for Aluminum 7075-T651
Abstract
Threshold stress intensity values for stress corrosion cracking K sub ISCC were determined for aluminum alloy 7075-T651 using two different testing techniques: a constant displacement, decreasing stress intensity technique achieved via a bolt-loaded specimen, and a constant load, increasing stress intensity technique. The test specimen geometry was an ASTM standard 3/4-inch (19 mm) compact type specimen. A constant immersion, 3.5 percent by weight sodium chloride environment was used for evaluating both techniques. Test times were limited to 2000 hours. For the test period examined, the constant displacement technique yields an approximately 50 percent higher threshold for corrosion cracking than does the constant load technique. The bolt-loaded technique offers simplicity, is inexpensive, and is a useful technique when used to rank materials as to their relative susceptibility to corrosion cracking; however, caution should be employed when comparing K sub ISCC values obtained via different test techniques.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1979
- Accession Number
- ADA077453
Entities
People
- John J. Ruschau
Organizations
- University of Dayton