Abstract
The stress-corrosion crack (SCC) growth behavior of 7N01 alloy in NaCl aqueous solution was investigated electrochemically and metallurgically. Using the compact DCB specimen technique, SCC growth-rate in short-transverse direction was determined as a function of aging treatment, solution pH and electrode potential. The results suggest that SCC propagation process is principally controled by localized anodic dissolution along grain boundary which may proceed in respects of local decrease in pH within the crack and resulting passive film rupture. It is found that the second phase particles on grain boundaries, causing exfoliation corrosion, play the role as the effective sites of cathodic reaction, which controles the anodic reaction, and accelerate SCC propagation.
