On the loading rate dependence of environment-assisted cracking in sensitized AA5456-H116 exposed to marine environments

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.