繊維強化プラスチックの長期寸法安定性

抄録

Fiber reinforced plastics (FRPs) have low thermal expansion and high specific stiffness compared to other structure materials. By applying FRPs to the structural material of precise machines such as antenna and mirror, not only the mechanical performance but also the functionality will be improved drastically. In spite of its excellent properties, the study in dimensional stability of FRPs isn't well discussed. In order to apply FRPs for such materials, we must discuss the long-term dimensional stability of FRPs. Dominant factors affecting the time-dependent deformation of FRPs are moisture absorption, viscoelastic behavior, shrinkages caused by chemical reactions and physical aging. The effects of these factors on dimensional stability are small, so we must discuss these factors in high accuracy. In this paper, conventional articles relating above the three factors in FRPs are cited wholly and main issues to be solved are clarified. The requirement of the dimensional stability was first discussed, and corresponding applications are then introduced. Second, moisture absorption behavior and the concept of CME (Coefficient of Moisture Expansion) are presented and the prediction of viscoelastic deformation is thirdly summarized. Finally, the effects of chemical shrinkage and physical aging against micro-deformation of FRPs are mentioned.