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Different phenolic resins have a direct impact on the properties of aramid paper honeycombs. It is important to study the relationship between phenolic resin and honeycomb properties. Two different phenolic resins are used to prepare aramid paper honeycomb core materials, and the compression properties, shear properties, flame retardancy and dielectric properties of the prepared honeycomb core material are tested. Combining the observation of resin end face resin distribution and contact angle measurement, the reasons for the difference in performance of honeycomb core materials prepared by two kinds of resins are analyzed. The results show that the temperature resistance of the resin itself directly affects the temperature resistance of the honeycomb and the volatilization rate of solvent water in the resin and the surface tension between the resin and the aramid paper affect the resin distribution of the resin on the honeycomb wall. When the content of the honeycomb core resin is the same, the resin rubber column at the end of the joint is beneficial to increase the compressive strength of the honeycomb core material, but the accumulation of the resin at the end of the node reduces the wall thickness of the honeycomb, resulting in a decrease in the shear strength and modulus of the honeycomb.

High-performance thermoplastic composites, due to their high toughness, excellent impact damage resistance and better fatigue resistance, are especially suitable for constructing special helicopter structures such as the landing gear, tail section, rotor hub and transmission drive shaft, which requires high damage-resistant, ballistic-tolerant, anti-fatigue properties. The application of high-performance thermoplastic composites in foreign helicopters is expanding from the application of key laminate structures to honeycomb sandwich structures, and a large number of low-cost and auto-mated manufacturing techniques such as in-situ automated fiber placement (AFP) and low-cost verification techniques such as virtual testing is being used. Limited by the low level maturity of domestic thermoplastic composites technology, high cost and long cycle of the traditional building block verification methods for the new composite system, the application of thermoplastic composites in domestic helicopter is still in initial stage, the performance stability and consistency of thermoplastic composites, supplementary low cost automatic manufacturing process, low density and high temperature core material and high-confidence efficient virtual qualification technology are needed to focus on the future.

The icing of helicopter rotor blades will lead to the destruction of its aerodynamic shape and seriously affect the flight quality. In order to improve the flexibility and fatigue resistance of helicopter rotor anti-icing system, the metal mesh braided with nickel alloy filaments is used as heating element, and the heating element is arranged in the blade in an extended way. Through the design, the diameter of wire and the size of mesh are determined. Combining with the existing composite material forming process, the electrical heating test pieces are prepared. The electrothermal performance test, mechanical property test and laboratory simulated deicing test of the prepared heating pad are carried out. The results show that the temperature rising speed of the heating pad is 2.5 ℃/s, the temperature uniformity in the plane is less than 2 ℃, and the simulated deicing effect in the laboratory is good.