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Based on the results of the IFMIF/EVEDA project in the broader approach (BA) activities, the conceptual design of the Advanced Fusion Neutron Source (A-FNS) to obtain irradiation data of DEMO blanket materials is under consideration in Japan. This paper describes the progress of the A-FNS conceptual design, which consists of a 40 MeV, 125 mA deuteron beam, a liquid lithium target system, and a test and post-irradiation test facilities. the main objectives of the A-FNS are the acquisition of RAFM irradiation data up to 2035 and the tritium recovery test on the blanket. In addition, it is expected to be used for various neutron researches. The technical design activities of the A-FNS are focused on improvement of the lithium target design, review of impurity criteria, remote handling, and irradiation application plan. [ABSTRACT FROM AUTHOR]

Abstract: The tritium permeation behavior through F82H steel from approximately pure tritiated water vapor diluted with He was investigated and the as-received and the permeation-experimented sample surfaces were analyzed by means of SEM, EDX and XRD. Extremely slow but obvious tritium permeation through F82H steel could be observed. It is indicated from the surface analyses that an oxide layer composed of magnetite and hematite is formed during the permeation experiments. The permeabilities estimated using the partial pressure of molecular tritium under the extreme assumption that the redox reaction among tritiated water vapor, magnetite and hematite with forming molecular tritium reaches equilibrium indicate that apparent tritium permeation using tritiated water vapor for the inlet side would be proceeded by molecular tritium generated by the redox reaction, although it is expected that actual tritium permeation would be derived from dissociated tritium atom indicated in transition state during the redox reaction. [Copyright &y& Elsevier]

The annihilation behavior of irradiation defects induced in neutron-irradiated Li2TiO3 and Li2ZrO3 were investigated with the tritium release behavior. It was revealed that the common characteristics in both samples were that the annihilation process of irradiation defects consisted of two first-order processes and E’-center could act as tritium trapping site, and otherwise was the way how the E’-center annihilated. The difference was suggested to attribute to the mobility of M as M4+ (or M3+, etc.). [ABSTRACT FROM AUTHOR]

The annihilation behavior of irradiation defects induced in neutron-irradiated Li2TiO3 and Li2ZrO3 were investigated with the tritium release behavior. It was revealed that the common characteristics in both samples were that the annihilation process of irradiation defects consisted of two first-order processes and E’-center could act as tritium trapping site, and otherwise was the way how the E’-center annihilated. The difference was suggested to attribute to the mobility of M as M4+ (or M3+, etc.). [ABSTRACT FROM AUTHOR]

Abstract: Recently, we have investigated the annihilation behavior of the radiation defects and the tritium release behavior in/from some neutron-irradiated ceramic breeder materials. In the present study, correlation between the tritium release and the annihilation of irradiation defects were investigated for neutron-irradiated Li2ZrO3. The annihilation of irradiation defects consisted of two processes, the fast and the slow processes. The activation energies for these processes were determined to be 0.32±0.01 and 0.80±0.01eV, respectively. The E′-center of irradiation defects was found to act as a tritium trapping site by comparison between the annihilation of irradiation defects and tritium release. From the present and the previous works, the annihilation process of oxygen vacancies such as E′-center and F+-center could play an important role in tritium behavior. The results of the present and previous studies suggest that there appears to be similar correlation between annihilation of irradiation defects and tritium release for several ceramic breeder materials. [Copyright &y& Elsevier]