Stress corrosion cracking behavior of X80 pipeline steel under alternating current, Desulfovibrio desulfurican and cathodic protection potential
Qi Fu, Qingyu Qin, Boxin Wei, Jin Xu, Changkun Yu, Cheng Sun
Abstract
The stress corrosion cracking (SCC) behavior of X80 pipeline steel under Desulfovibrio desulfurican (D. desulfurican), alternating current (AC) and cathodic protection (CP) was studied by the constant load tests and slow strain rate tensile (SSRT) test. The results showed that both AC interference and relatively negative CP potential aggravated pitting corrosion and enhanced the SCC susceptibility under the constant load. In the saline soil environment containing D. desulfurican, the AC greatly contributed to the cracking tendency of X80 pipeline steel and resulted in the safe CP range that was too narrow for practical engineering application, thus requiring appropriate discharge methods.