Effect of plasticity on stress corrosion cracking behavior of X-52 pipeline steel in near-neutral pH environment

This research focused on the effect of plasticity on stress corrosion cracking (SCC) of pipeline steel (X-52) in near-neutral pH environment. A simulated near-neutral pH soil solution, termed C1, was used for all the tests. The effects of elastic and plastic deformation on corrosion current were studied. Crack advance was measured in samples with various amounts of plastic deformation by three different techniques, slow strain rate tests (SSRT), potential drop tests and surface replica tests. Crack morphologies and the crack features on the fracture surface were observed by optical microscopy (OM) and scanning electron microscopy (SEM).; All the cracking tests indicated that the cracking rate was enhanced by the plastic deformation. The electrochemical tests showed that corrosion current increased with plastic deformation. The relationship between the cracking mechanisms and plastic deformation was discussed.