TY - GEN
T1 - Hydrogen trapping in X70 structural pipeline steel and weldments
AU - Sezgin, Jean Gabriel
AU - Fjær, Hallvard G.
AU - Matsunaga, Hisao
AU - Yamabe, Junichiro
AU - Oldeng, Vigdis
N1 - Funding Information:
This work is performed within the project Knowledge Basis for Repair Contingency of Pipelines (234110/E30) funded by the Research Council of Norway, Statoil, Gassco, Technip, EFD Induction and POSCO.
PY - 2018
Y1 - 2018
N2 - Diffusion measurements and thermal desorption measurements have been performed on a X70 pipeline steel, in as received and normalized and quenched condition, after being hydrogen charged for 200 h at 100 MPa hydrogen gas pressure and 85℃. Numerical simulations based on the assumption of thermodynamic equilibrium were performed, aiming to compare the trapping energies when fitting to the TDS spectra. TDS experiments revealed a reversible trap site with activation energy of 26.2 kJ.mol-1. Irreversible trap sites with an activation energy of >100 kJ.mol-1 were observed from both as-received and heat-treated condition. In contrast, a reversible trap site with an activation energy of 49.2 kJ.mol-1 was observed only from the heat-treated condition. The numerical modelling based on the assumption of equilibrium between hydrogen in traps and hydrogen in lattice is seen to provide a good fit to the experimental data.
AB - Diffusion measurements and thermal desorption measurements have been performed on a X70 pipeline steel, in as received and normalized and quenched condition, after being hydrogen charged for 200 h at 100 MPa hydrogen gas pressure and 85℃. Numerical simulations based on the assumption of thermodynamic equilibrium were performed, aiming to compare the trapping energies when fitting to the TDS spectra. TDS experiments revealed a reversible trap site with activation energy of 26.2 kJ.mol-1. Irreversible trap sites with an activation energy of >100 kJ.mol-1 were observed from both as-received and heat-treated condition. In contrast, a reversible trap site with an activation energy of 49.2 kJ.mol-1 was observed only from the heat-treated condition. The numerical modelling based on the assumption of equilibrium between hydrogen in traps and hydrogen in lattice is seen to provide a good fit to the experimental data.
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M3 - Conference contribution
AN - SCOPUS:85053463597
SN - 9781880653876
T3 - Proceedings of the International Offshore and Polar Engineering Conference
SP - 228
EP - 235
BT - Proceedings of the 28th International Ocean and Polar Engineering Conference, ISOPE 2018
PB - International Society of Offshore and Polar Engineers
T2 - 28th International Ocean and Polar Engineering Conference, ISOPE 2018
Y2 - 10 June 2018 through 15 June 2018
ER -