Corrosion fatigue crack growth rate in sensitized alloy 600 in thiosulfate solution at room temperature

Corrosion fatigue crack growth (FCG) behavior of alloy 600 (UNS N06600) sensitized at 1,100°C/0.5 h + 700°C/5 h in 0.1 M sodium thiosulfate (Na₂S₂O₃) solution at room temperature under applied anodic potential conditions was investigated using the fracture mechanics technique. Results indicated the FCG rate depended upon the testing frequency and the applied potential. At a frequency of 1 Hz, FCG rates were independent of applied potential and nearly the same as those tested in a N₂ atmosphere. However, at a frequency of 0.1 Hz, the FCG rate Increased with Increasing applied potential. Moreover, the competition between environmental and mechanical effects Influenced the fracture morphology of the corrosion fatigue of sensitized alloy 600.