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Kinsho, Michikazu; Saito, Yoshio*; Kabeya, Zenzaburo*; Tajiri, Keisuke*; Nakamura, Tomaru*; Abe, Kazuhiko*; Nagayama, Taketoshi*; Nishizawa, Daiji*; Ogiwara, Norio
Vacuum, 73(2), p.187 - 193, 2004/03
Times Cited Count：17 Percentile：54.92(Materials Science, Multidisciplinary)Alimina ceramics vacuum duct has been developing at JAERI for the 3GeV-RCS of the J-PARC project. There are two type of the alumina ceramics vacuum ducts, one is a 1.5m-long duct with a circular cross section for use in the quadrupole magnet, the other is a 3.5m-long being bending 15 degree with an elliptical cross section for use in the dipole magnet.These ducts could be manufactured by brazed jointing several duct segments of 0.5-0.8 m long. Since some electrically conductive boundary is necessary to form on the ceramics duct in order to reduce the duct impedance, the alumina ceramics ducts have copper stripes on the outside surface of the ducts. This is called for rf shielding system. The copper stripes as rf shielding is produced by an electroforming method. In order to reduce emitting secondary electrons when primary protons or electrons impinge onto the surface, TiN film is coated inside surface of the alumina ceramics duct.
Kinsho, Michikazu; Ogiwara, Norio; Wada, Kaoru*; Yoshida, Motoo*; Nakayasu, Tatsuo*; Yamato, Yukio*
Vacuum, 73(2), p.175 - 180, 2004/03
Times Cited Count：4 Percentile：20.5(Materials Science, Multidisciplinary)The turbo molecular pump which can be operated exposed to high radiation has been developing at JAERI and Osaka Vacuum Ltd., because it is planed to use this turbo molecular pump for the 3GeV-RCS of the J-PARC project. The goal of irradiation dose is 30 MGy because the cumulative energy dose due to radiation is approximately estimated to be on the order of 100 MGy for 30 years of the 3GeV-RCS operation. In order to know radiation damage of turbo molecular pump, gamma-ray irradiation experiment has been performed at JAERI. The turbo molecular pump could operate properly less than 3.5 MGy absorption dose under gamma-ray irradiation environment. Since the elongation of elastomer vacuum seals became small due to exposed to radiation, this radiation damage of elastomer seals causes leak. The turbo molecular pump components except the elasomer seals, for example motor coil, control sensor, and etc, have kept high performance more than 7 MGy absorption dose. The turbo molecular pump without elastomer seals has been developed and the irradiation test will be started form April.
