Co-authors​ :

 Xudan YAO (CHINA), Yaxin WANG , Yaqi WANG , Weibang LYU (CHINA), Wandong WANG (CHINA), Yu'E MA  

Anti-icing/de-icing (AI/DI) is vital for flight safety, which is conventionally achieved by hot air bleed systems, while facing new challenges for the latest generation aircraft with composite wings. Electro-thermal systems are promising alternatives, owing to their high energy efficiency, low maintenance requirements and the absence of bleed exhaust holes [1,2]. In particular, carbon fibre reinforced plastics (CFRPs) integrated with heating elements, e.g., carbon nanotubes (CNTs)/glass fibre reinforced plastics (GFRPs), was thought as one promising candidate for aerostructures with AI/DI functions. However, the difference of thermal expansion between different components, i.e., CNT, GFRP, CFRP, will ignite the internal stress between interfaces under the cyclic thermal loading, and then affect the strength of composite structures, especially the interfacial properties. Regarding the thermal load of the aircraft, on one hand, temperature profile (Figure 1a) indicates the external static air during the flight, ranging from -56℃ to 20 ℃ [3]. On the other hand, -20℃ to 10 ℃ possesses the highest risk of ice accretion, while with the AI/DI system switched on, the temperature will range from -20℃ to 80 ℃ [4,5]. In combination, the temperature range for the thermal cycling is set from -56℃ to 80 ℃ (Figure 1b) in this work. As the CNT/GFRP heating element is integrated into the composite, the laminate could be either internally heated through resistive heating or externally heated by the oven. CNT/GFRP/CFRP composites with different thermal cycles and heating rates, under external and internal heating will be investigated and compared. In addition, the effect of the laminate layup on the heating and mechanical properties will also be studied. The interlaminar shear strength (ILSS) combined with the microstructural morphology of CNT/GFRP/CFRP composite laminates will be characterized to evaluate the influence of thermal cycling on the composites.