Hydrogen-Induced Cracking (HIC)
Hydrogen-induced cracking is caused by nascent hydrogen atoms (Ho),
usually produced in aqueous hydrogen sulphide (H2S). Hydrogen atoms
produced, for example, by the corrosion reaction of iron, usually combine to
form hydrogen gas molecules. However, in the presence of sulphide or cyanide,
the hydrogen recombination reaction is poisoned so that the nascent hydrogen
atoms diffuse into the steel rather than recombining on the metal surface to
form hydrogen gas. Hydrogen atoms that enter the pipeline can cause
embrittlement and failure. Usually HIC failures occur within a few weeks of the
pipeline being put in service.
The objective of the PICon/HIC section is to disseminate information on pipeline
HIC. Please let PICon know your ideas, suggestions
and thoughts on issues related to pipeline HIC.
PICon organizes an online journal. The schedule and papers published by the Journal are available at
PICon Journal.
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