| 摘要 |
PURPOSE:To obtain a fiber reinforced plastic with excellent crack resistance at very low temperature having a structure of cylinder bottom plate where helium does not leak by winding a fiber structure, which has negative expansion fiber as a warp and positive expansion fiber as a weft for fiber material, such that the warp will be at a specific angle with respect to an axis of a molded body so as to mold integrally with resin. CONSTITUTION:An outside cylinder 1 of CFRP has an outside flange and an inside cylinder 2 of FRP consisting of organic fiber has an inside flange. In the inside cylinder 2 of the cylindrical FRP consisting of the organic fiber, negative expansion fiber, for example, a polyethylene fiber is used for warp and positive expansion fiber, for example, glass fiber is used for weft as a fiber material. The fiber structure is wound on an axis of a molded body such that the warp is at + or -40-90 deg. with respect to the axis and molded integrally with resin, for example, epoxy resin. The fiber reinforced plastic does not contract in the peripheral direction at very low temperature or expands, so that helium does not leak. |
