<論文>超高速回転FW円板の残留熱応力と座屈

概要

論文の詳細を見る
Much attention has been paid to the high-performance fiber reinforced plastic flywheels to store the kinetic energy. However, in the circumferentially filament-wound (FW) flywheels, the cracks are apt to occur along fibers owing to the radial tensile stress due to the thermal residual stress occurred during curing besides the rotational stress. In the present paper, keeping in mind the residual stress under such circumstances, the analytical formulae were first presented to predict the thermal residual stress and the buckling temperature drop in hybrid discs wound by using glass- and carbon-fibers in inner and outer sides, respectively. Various kinds of disc specimens with different diameters, thicknesses and winding compositions were manufactured. The occurrences of buckling and crack failures were checked in these specimens after curing. The thermal residual stresses were measured by using a technique of cutting away the inner edge successively. The comparison of experimental evidences with the analytical predictions on thermal stress, buckling and crack failure suggests that the temperature at which the hardening begin can be assumed to be about 150℃, reasonably in the elastic analysis for fiber reinforced epoxy composites. It was also found that the use of soft epoxy resin of rubber type was effective to reduce the residual stress and suppress the crack initiation.
宇宙航空研究開発機構の論文