Influence of Thermal Conductivity on Stacking Sequence of Hybrid Composites

Hybrid Composites comprising of two or more reinforcement materials are finding increase in demand in diverse field of applications such as building panels, automotive components and aero parts. There is a need to study the thermal properties to find the suitability of hybrid laminates as insulating materials. In this research article an attempt is made to find the thermal conductivity of laminate materials having varying stacking sequence of its reinforcement fibers. The said laminate is produced using hand layup method. It contain seven layers of reinforcement fibers stacked one over other in three different configurations. First the reinforcements kevlar (K49) and basalt fibers are stacked in alternating layers. Second configuration contain bilayers of kevlar or basalt sandwiching the inner three alternative layers. Third configuration contain tri layer of one of the reinforcement fibers sandwiched between bilayers of another reinforcement fibers. Epoxy resin is used as binding cum matrix element in all the hybrid laminates. The produced hybrid laminates are tested for its thermal conductivity and coefficient of thermal expansion. It is found that increasing the number of layers of basalt fibers increased the thermal conductivity of the hybrid laminate. On the other hand, kevlar fibers contributed in reducing the thermal conductivity of the hybrid laminates. Thermal expansion coefficient depended on the presence of basalt fibers as the outermost layers in the hybrid laminates. The hybrid laminates having kevlar fibers contributed in lowering thermal conductivity and also the coefficient of thermal expansion.