Filament-Wound Kevlar 49/Epoxy Pressure Vessels.

摘要

The performance of an organic fiber (Keviar 49) has been investigated. First, a detailed study of the strength of fiber/epoxy strands was completed. Variables studied included: fiber uniformity, strength distribution at room and LN2 temperatures, stress-strain characteristics, strain rate effect on the fiber strength, stress-rupture behavior, and ageing under no load. Second, the composite performance in filament-wound pressure vessels was studied. Variables studied included: spherical vs cylindrical vessels, cylinderical vessel design and size, winding patterns, reproducibility, pressurization rate, fatigue, and effect of liquid hydrogen temperatures. Third, a study was made of the acoustic emission generated during tensile tests of the fiber/epoxy strands, tensile tests of fiber/epoxy elongated NOL rings, burst tests at room temperature of the cylindrical and spherical pressure vessels, and vessel fatigue tests. Fourth, a microstructural characterization of the failure mode of the fiber was carried out using transmission and scanning electron microscopy and optical microscopy. Fracture surfaces of bare fibers were compared with epoxy impregnated strands from tensile tests, pressure vessels, and NOL rings. (MM).