Ceramic particulate thermal barrier surface coatings for glass fibre-reinforced epoxy composites

Abstract

This study investigates the thermal barrier efficiency of five commercially available ceramic nano and micro particles deposited on the surfaces of glass fibre-reinforced epoxy composites (GRE). Two approaches of application of deposition of ceramic particles have been undertaken, firstly where the ceramic particles were dispersed in a phenolic resin binder and applied on a GRE surface by a K-bar coater and the second where extra ceramic particles were sprayed on the first coating while the resin was partially cured to enable the surface to be completely covered by ceramic particles, leaving no resin exposed. The thermal barrier efficiency of these coatings was evaluated from the cone calorimetric parameters at incident heat fluxes of 35 and 50 kW/m2 as well as from temperature gradient through the samples’ thicknesses, measured by inserting thermocouples on the exposed and back surfaces during the cone tests. The morphology and durability of the coatings to water absorption, peeling, impact and flexural loading were also studied. The results showed that the surface layers of all coated samples were uniform and there was a strong adhesion between the coating and the substrate. Moreover, they did not adversely affect the mechanical properties of GRE composite while improving the mechanical property retention of GRE composites after exposure to heat.