The fracture properties of 2(1/4)Cr-1Mo steel for hydrogenation reactor wall-material were investigated

in the environment of high temperature and pressurized hydrogen.Fracture toughness values were measured for original steel

electrochemically hydrogen charging

step cooled down and step cooled down plus thermally hydrogen charging.Stress intensity factors of crack tip were calculated for burial crack and surface crack by using fracture mechanics.The results showed that step cooled down increased fracture toughness and the presence of hydrogen reduced fracture toughness of 2(1/4)Cr-1Mo steel.Without surface crack in reactor’s inside wall the operation of reactor is safe.