Investigation on stress corrosion cracking of API 5L X65 steel in CO2 corrosion medium

This investigation studied the simultaneous effect of temperature (in the range of 30-70 degrees C) and NaCl concentration (in the range of 1-20 wt%) on stress corrosion cracking behavior of API 5L X65 steel in CO2 corrosion medium. The results of slow strain rate tensile test and surface characterization revealed that SCC susceptibility increased by an increase in temperature and a decrease in NaCl salt concentration. Furthermore, potentiodynamic polarization technique was employed in case of condition with the highest SCC susceptibility and illustrated that contribution of anodic dissolution and hydrogen involvement was the main SCC mechanism.

Automated summary

This study found that the susceptibility to stress corrosion cracking of API 5L X65 steel in CO2 corrosion medium increases with higher temperature and lower NaCl concentration. Additionally, in conditions of highest SCC susceptibility, anodic dissolution and hydrogen involvement were identified as the main SCC mechanisms through potentiodynamic polarization technique.