(CorrosionBook)SULFIDE STRESS CRACKING RESISTANCE OF API-X100 HIGH STRENGTH LOW ALLOY STEEL IN NACE TM0177 SOLUTION

摘要

Sulfide Stress Cracking (SSC) of API-X100 high strength low alloy steel was evaluated in H2Ssaturated NACE solution “A” at room temperature. The corrosion rate, utilizing electrochemicalpolarization techniques, in the solution was 97 mpy. Proof ring testing, per NACE TM0177, generated anSSC threshold stress value of 46% of yield strength. SSC susceptibility was caused by the high corrosionrate which formed corrosion pits that acted as crack initiation sites on the metal surface and provided morehydrogen to migrate into the steel. In addition, the X100 inhomogeneous microstructure provided a highdensity of hydrogen traps which promoted hydrogen embrittlement.