Potential-pH Diagrams of Stress Effects on Occluded Cell Corrosion Inside Stress Corrosion Cracks Available to Purchase

The construction of experimental potential-pH diagrams depicting both thermodynamic and kinetic behaviors inside a pit or crack during its propagation was described in detail. This study included the procedures and methods for determining the related thermodynamic and kinetic curves, corrosion rates during the different stages of propagation, and the critical pH value below which the film on the crack tip ruptured completely and the corrosion process accelerated. The system 18% chromium (Cr)-9% nickel (Ni)-titanium (Ti) stainless steel (SS)-chloride (Cl^–) was used to draw the potential-pH diagrams with and without stress as demonstration examples. Effects of stress on occluded cell corrosion (OCC) were shown by comparing the diagrams. Stress reduced passivation ability, increased corrosion rates, and increased the critical pH value.