EFFECT OF NANO-PAPER COATING ON FLEXURAL PROPERTIES OF A FIRE-TREATED GLASS FIBER-REINFORCED POLYESTER COMPOSITE

摘要

Planned re-usable aerospace vehicles require materials with high specific strength to withstand thermal shock associated with repeated re-entry into Earth's atmosphere. Composites, such as glass fiber-reinforced polyester (GRP), have rapidly become preferred for high value structural components requiring high specific strength and durability. Their ability to sustain high tensile loads, impact loads, and the like, has .allowed them to be used as light-transmitting panels, fuselages, nose cones, and combustor nozzles. As a part of service conditions, heat flux strongly alters mechanical properties with exposure time. The effect of including a carbon nano-paper coating on the monotonic flexural properties of a GRP composite is analyzed. The nano-paper acts as a thermal barrier to protect the underlying material in the presence of above glass-transition temperatures. A series of three-point bend experiments was performed on specimen-sized samples of composites subjected to various levels of heat fluxes across numerous exposure times. Analysis of these experiments reveals trends in the deformation mechanisms of these materials near failure. Correlations of flexural modulus and critical load are used to develop models for strength.