Neutron transmission experiment of boron-doped resin for the JT-60SC neutron shield using 2.45 MeV neutron source

Morioka, Atsuhiko; Sato, Satoshi; Ochiai, Kentaro; Sakasai, Akira; Hori, Junichi; Yamauchi, Michinori*; Nishitani, Takeo; Kaminaga, Atsushi; Masaki, Kei; Sakurai, Shinji; Hayashi, Takao; Matsukawa, Makoto; Tamai, Hiroshi ; Ishida, Shinichi

Neutron shielding material of the port section of JT-60 superconducting modification (JT-60SC) serves as a design which used resin (KRAFTON-HB4) excellent in the temperature characteristic from polyethylene. In order to make port weight mitigate and reduce the nuclear heating of the superconducting coil, we were developed the resin which added natural BORON to resin. The 2.45MeV neutron generated in the D-D reaction was irradiated, the penetration of the neutron was measured in some kinds of samples which changed the amount of BORON, and the shielding performance of the resin containing BORON was compared with them. The penetration rates of fast neutron flux do not depend on the doped density of boron in both measurements. Whereas the penetration rates of thermal neutron flux in the resin with 2 wt% B are about 25% lower than those with 1 wt% at the back surface of the test specimens.