Proceedings of the Third International Conference on Metals & Hydrogen P16

Hydrogen effects on the mechanical behavior of different quenched and tempered steels

L.B.Peral (1)1 , A. Zafra (1)1 , C. Rodríguez (1)1 , J. Belzunce (1)1

  • (1) 1

    School of Engineering, University of Oviedo, campus universitario, 33203 Gijón, Spain


In order to select the most appropriate steel to deal with pressurized hydrogen during long times, the susceptibility to hydrogen embrittlement of 2.25Cr1Mo steel, quenched and tempered at two different temperatures, and 2.25Cr1Mo0.3V was evaluated by means of tests performed on pre-charged specimens in an hydrogen reactor at 195 bar and 450ºC during 21 hours. Different specimens were employed: cylindrical samples to measure the hydrogen content and its desorption kinetics at room temperature, smooth and circumferentially notched tensile samples and compact tensile specimens to determine the steel fracture toughness. Finally, scanning electron microscopy was used in the study of fracture surfaces. Using the aforementioned pre-charge conditions, significant amounts of hydrogen were introduced. On the other hand, the conventional tensile properties were not modified by the presence of hydrogen, but the ductility measured on the notched specimens was affected, especially in the hardest grade and under the lowest displacement rate. Moreover, the presence of hydrogen has notably decreased the steel fracture toughness and significant changes in the fracture micromechanisms have also been observed.


  • low-alloyed ferritic steels
  • hydrogen embrittlement
  • fracture mechanisms