DESIGN AND MANUFACTURING OF FILAMENT-WOUND ELASTOMERIC MATRIX COMPOSITE FLYWHEELS

A procedure for the filament winding of thick glass and carbon fiber r einforced urethane matrix composite flywheels is presented. The impetu s for fabrication of urethane matrix composite rings, which is discuss ed in the paper, stems from several potential advantages they may offe r in high speed flywheels over conventional rigid epoxy matrix rings. The method developed uses continuous in-situ curing of the part while it is being wound to avoid compositional variations throughout the thi ckness, to eliminate fiber waviness and also to allow very high speed manufacturing. Urethanes typically have extremely high room-temperatur e viscosities and very short elevated temperature pot lives which comb ine to make conventional fiber impregnation schemes difficult. A metho d of diluting the resin with a solvent was developed in order to lower the viscosity. This method allows good room temperature fiber impregn ation while avoiding the waste generated with continuous resin mixing systems for elevated temperature impregnation. After impregnation, hea ters flash the solvent from the tow prior to being wound into the part . Results show that high quality parts with high fiber content (about 60%) and low void content (less than 1%) can be easily fabricated at r adial deposition rates as high as 3.23 cm/hr (1.27 in/hr).