Definitions for "Hydrogen embrittlement"
The corrosive effect produced on steel armor of survey cables and other steel equipment by the penetration of hydrogen released from the decomposition of hydrogen sulfide, H S. The presence of H S in wellbore fluids will result in a degree of embrittlement in steel equipment unless the steel has been protected by an inhibitor, or the pH of solutions has been otherwise controlled.
Steel fasteners exposed to hydrogen can fail prematurely at a stress level well below the materials yield strength. Hydrogen embrittlement occurs in fasteners usually as a result of the part being exposed to hydrogen at some time during its manufacturing process but it can also occur through in-service corrosion. Electroplating is generally considered to be a major cause of hydrogen absorption in steel fasteners due to the release of hydrogen during this process. Higher strength steels are more susceptible to hydrogen embrittlement than lower strength steels, however it is considered that there is no lower strength limit. As a rule of thumb, steels below Rockwell C 35 are considered to be far less susceptible. Tests such as the incremental load hydrogen embrittlement test can be completed to assess if hydrogen embrittlement is present in a batch of fasteners.
The brittleness induced in steel by the absorption of atomic hydrogen, most commonly from a pickling or plating operation.