Effect of noble-gas bubbles on deuterium trapping behavior in argon pre-implanted stainless steel

Ion implantation technique and nuclear reaction analysis were used to study the trapping behavior of deuterium by radiation defects in 316 austenitic stainless steel. Defect structure with a different ratio of displacement per atom (dpa) to argon gaseous impurity along with a depth has been formed by pre -irradiation of SS316 with 1.4 MeV argon ions. The deuterium migration between layers containing various defect types served as an indicator of traps strength. Computational evaluation of deuterium trapping process within the framework of the diffusion-trapping model has shown that gas-bubbles associated traps turn out to be a strongest deuterium traps with a binding energy of 0.74 eV. Other irradiation-induced defect types have a weaker effect on deuterium retention in austenitic steel. Experimental ob-servations and calculation results are discussed with respect to the possibility of molecular hydrogen formation in radiation-induced nanovoids under operating conditions of water-cooled reactor internals.(c) 2022 Published by Elsevier B.V.

Automated summary

Ion implantation technique and nuclear reaction analysis were used to study the trapping behavior of deuterium by radiation defects in 316 austenitic stainless steel. The study showed that gas-bubbles associated traps are the strongest deuterium traps.