STATE-OF-THE-ART FIBER-REINFORCED-PLASTIC CRYOSTATS IN JAPAN

Fibre-reinforced-plastic ( FRP) cryostats have been developed for vari ous cryogenic fields, such as superconducting magnets and cryogenic el ectronics. The FRP cryostats ought to be used as liquid-helium contain ers for the operation of a.c. and/or pulse superconducting magnets bec ause the eddy-current losses induced in the metallic cryostats would b e too large to operate the magnets stably. They are also needed for SQ UID operation because the metallic cryostats disturb the weak magnetic signals that are to be detected by the SOUID system. The material pro blems and possible answers are summarized. The construction of FRP cry ostats is demonstrated. Recently developed FRP cryostats for practical applications in Japan are reviewed.