Irradiation effect of D-T neutron on superconducting magnet materials for fusion

Nishimura, Arata*; Hishinuma, Yoshimitsu*; Seo, Kazutaka*; Tanaka, Teruya*; Muroga, Takeo*; Nishijima, Shigehiro*; Katagiri, Kazumune*; Takeuchi, Takao*; Shindo, Yasuhide*; Ochiai, Kentaro; Nishitani, Takeo; Okuno, Kiyoshi

A fusion device which creates burning plasma will be equipped with a superconducting magnet system to provide strong magnetic field and maintain the burning plasma. The fusion device also will have plasma heating devices such as neutral beam injectors and electron cyclotron systems. Since these systems need several ports to carry in the energy into plasma, the fusion device has large ports connecting to the systems locates in outside of cryostat. Through these ports, D-T neutron will come out of the burning plasma and damage the surrounding materials. The superconducting magnets also will be irradiated by the streaming neutron. To investigate mechanisms of degradation of superconducting properties, and to construct database of irradiation effect on superconducting magnet materials, a cryogenic target system has been install in Fusion Neutronics Source (FNS) at Japan Atomic Energy Agency (JAEA). The irradiation tests with D-T neutron have been carried out three times and some irradiation effects on superconducting magnet materials are clarified. In this paper, the present status of the cryogenic target system and some irradiation test results will be summarized and presented.