Thermal desorption characteristics of several charge stripper carbon films for J-PARC RCS

Kamiya, Junichiro; Kinsho, Michikazu; Yamazaki, Yoshio; Yoshimoto, Masahiro; Yanagibashi, Toru*

Journal of the Vacuum Society of Japan, 60(12), p.484 - 489, 2017/12

https://doi.org/10.3131/jvsj2.60.484

Multi-turn H charge exchange injection is employed as a beam injection method in the 3-GeV RCS (Rapid cycling synchrotron) at J-PARC (Japan Proton Accelerator Research Complex). In this method, injection H beam is put on the same orbit as already circulating proton (H) beam in a dipole magnetic field due to the opposite curvature of the injected and circulating beams. In the straight section, where the two beams coincide with each other, both beams are passed through a thin foil, which strips two weakly bound electrons off each H ion, forming an intense beam of protons. The thin foil, which is mostly made of carbon, would be the source of the outgassing, especially when its temperature rises due to the beam hitting. Therefore it is important to estimate the amount and components of the outgassing from the charge stripping foil. In this paper, we will report the thermal desorption measurement results for the several foil, which is used as the charge stripping foil in the RCS.

Evaluation of the cryogenic tensile properties for aramid fiber rod

Saito, Toru; Okubo, Toshikazu*; Izumi, Keisuke*; Okawa, Yoshinao*; Kobayashi, Norihiro*; Yamazaki, Toru; Kawano, Katsumi; Isono, Takaaki

Teion Kogaku, 50(8), p.400 - 408, 2015/08

https://doi.org/10.2221/jcsj.50.400

Aramid fiber-reinforced plastic (AFRP) has been developed as a structural material that has the advantages of light weight and high strength. In this study, tensile tests were carried out to measure the tensile properties of AFRP rod on the market for reinforcement of concrete at room temperature, 77 K and 4.2 K. Especially at cryogenic temperatures, it is difficult to perform a tensile test of the bar because the specimen slips through the jig grip. To prevent the rod from slipping, tensile tests were carried out with some filling conditions. The applicable and appropriate tensile test conditions were established by modifying the jig grip, treating the surface of the rod and using cryogenic epoxy infill to grip the rod. They were more than 1100 MPa. Additionally, the AFRP rod included a temperature dependence in which the Young's modulus increased as the test temperature decreased. It was confirmed that the Young's modulus increased because aramid fiber was more dominant than epoxy.

Mechanical properties of high manganese austenitic stainless steel JK2LB for ITER central solenoid jacket material

Saito, Toru; Kawano, Katsumi; Yamazaki, Toru; Ozeki, Hidemasa; Isono, Takaaki; Hamada, Kazuya*; Devred, A.*; Vostner, A.*

Physics Procedia, 67, p.1016 - 1021, 2015/07

https://doi.org/10.1016/j.phpro.2015.06.193

Test results of CS insert for ITER; Test method

Isono, Takaaki; Kawano, Katsumi; Ozeki, Hidemasa; Saito, Toru; Nabara, Yoshihiro; Suwa, Tomone; Shimono, Mitsugu; Ebisawa, Noboru; Sato, Minoru; Uno, Yasuhiro; et al.

no journal, , 

JAEA is procuring conductors for ITER Central Solenoid (CS) and has evaluated its superconducting performance using CS Model Coil Test facility. We measured Tcs values during cyclic charge of 16,000 cycles and warm-up and cool-down cycle of 3 times. And we measured effect of coil deformation by electro-magnetic force on Tcs values and performed quench test. In this presentation, test method will be reported.