On the loading rate dependence of environment-assisted cracking in sensitized AA5456-H116 exposed to marine environments. (June 2022)

• Record Type: Journal Article
• Authors: Harris, Zachary D.; Burns, James T.
• Is Part Of: Corrosion science. Volume 201(2022)
• Publication Date: 2022-06
• Subjects: Al-Mg -- 5xxx-series aluminum -- Environment-assisted cracking -- EAC -- Loading rate; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2022.110267
• Languages: English
• ISSNs: 0010-938X

Abstract

Abstract: The influence of the applied loading rate (dK/dt) on the environment-assisted cracking (EAC) behavior of sensitized AA5456-H116 in 0.6 M NaCl at applied potentials ranging from −800 to −900 mVSCE is assessed via a rising-K testing framework. The applied potential strongly affects the dK/dt-dependence of EAC with results suggesting a minimal influence for potentials more positive than −830 mVSCE and a stronger dK/dt-dependence for potentials more negative than −830 mVSCE . Crack growth rates measured using rising versus static K testing are compared, which demonstrates that rising K methods consistently yield conservative EAC metrics with increased efficiency. Highlights: The effect of dK/dt on EAC in sensitized AA5456-H116 depends on applied potential. EAC is effectively dK/dt-independent for potentials more positive than − 830 mVSCE . EAC is strongly dK/dt-dependent for potentials more negative than − 830 mVSCE . Differences in dK/dt dependence are linked to EAC mechanism for Al-Mg alloys. Rising K-based testing consistently yields efficient and conservative EAC metrics.