極低温用高性能スペーサーの開発

高強度ポリエチレン繊維/ガラス繊維系一方向強化複合材料の圧縮特性及び熱歪特性

抄録

Unidirectional hybrid composites reinforced with high-strength polyethylene fiber and glass fiber were prepared to develop a spacer having a low thermal expansion coefficient for cryogenic use. The thermal expansion coefficient and compressive strength of the hybrid composites were measured together with the effect of thermal cycling between room and cryogenic temperatures. Though the hybrid composites showed anisotropy in the thermal expansion coefficient, the coefficient could be calculated by the law of mixtures. The thermal expansion coefficient became zero when the ratio between polyethylene and glass fiber volume was 3/7. The compressive strength and thermal expansion coefficient did not change after 5 heat cyclings. The compressive modules of the hybrid composite was approximately 50GPa at small strain and then decreased slightly. The breaking energy and strain of the hybrid composite were larger than those of the composites reinforced by polyethylene or glass fiber. The compressive strength of hybrid the composite can be expressed by the law of mixtures.