Hydrogen Stress Cracking
Cracking that results from the presence of hydrogen in a metal and tensile stress (residual and/or applied)
NOTE HSC describes cracking in metals that are not sensitive to SSC but which can be embrittled by hydrogen when galvanically coupled, as the cathode, to another metal that is corroding actively as an anode. The term “galvanically induced HSC” has been used for this mechanism of cracking.
[ISO 15156-1:2009, definition 3.13]
Source: ISO 21457:2010, Petroleum and natural gas industries — Materials selection and corrosion control for oil and gas production systems, First Edition,September 2010. Global Standards