Standard and Vanadium enhanced 2.25Cr1Mo plate steels (ASTM A387 gr. 22 and A542 type
D) are generally used in high-temperature and high-pressure hydrogen environments. In such
environments, significant quantities of hydrogen are soluble in the steel. The influence of hydrogen on
mechanical properties during a shut–down operation and on creep properties has been considered.
Mechanical property testing of steels exposed to the above stated environments was conducted
in order to determine the effect of hydrogen. Tensile, Charpy V-Notch CVN, and fracture toughness
values were determined after exposure to high pressure hydrogen at high temperatures, for base metal,
heat-affected zone (HAZ), and weld metal specimens.