Nitrogen contamination effect on yttrium gettering of hydrogen in liquid lithium

Yttrium is a candidate for hydrogen hot trapping in a liquid tritium breeder of a fusion reactor blanket and in the flowing target of the International Fusion Materials Irradiation Facility, IFMIF. Nitrogen impurity in lithium is expected to decrease hydrogen trapping but this has not been confirmed. This study, directed at developing a hydrogen permeation device as a hydrogen concentration monitor in lithium, investigated hot trapping by yttrium in lithium. The hydrogen trapping rate of yttrium first aged in lithium containing nitrogen was smaller than the rate without nitrogen contamination. Nitrogen in contaminated yttrium did not form yttrium nitride, and the nitrogen diffused much deeper into the yttrium than did oxygen.