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In terms of the composite preforms weaving process, the influence of the length, width, height and speed of the weaving needle on the weaving capacity is analyzed. According to the calculated kinetic energy, potential energy, and virtual work of the weaving needle and the guide array, the system dynamic equation is established based on Hamilton’s principle, and the discrete processing is performed. According to the state equation, the Runge-Kutta method is used to solve the vibration response of the weaving needle free end. The correctness of the theoretical model is verified with ADAMS by analyzing the system dynamics. The variation of the free end vibration response was studied with time under different parameters. It is found that the velocity, length, and height parameters of the weaving needle have a greater influence on the vibration amplitude and the deflection of the equilibrium position. The comprehensive influence of velocity and size parameters on the weaving capability is discussed. Based on the above results, the analysis concludes that the width of the weaving needle has the smallest influence on weaving capability. The short-high weaving needles have great weaving capability. The increase in velocity can reduce the vibration amplitude and improve the weaving efficiency, but there is a limit to the improvement of the weaving capability.

SiO2 particles were modified by γ-aminopropyltriethoxy silane (KH550) and γ-(2,3-epoxypropoxy)propyltrimethoxy silane (KH560) in sequence to prepare SiO2 particles with silicone-methoxy groups on surface (SiO2-s-Si(OCH3)3). X-ray photoelectron spectroscopy (XPS) and thermal gravimetric analysis (TGA) were used to characterize the modified SiO2 particles. The SiO2-s-Si(OCH3)3 particles and tetramethoxysilane were used to co-cure hydroxyl silicone oil. The strong interfacial interactions between silicone rubber and fillers, which came from hydrolyzed SiO2-s-Si(OCH3)3 particles in situ reacting with hydroxyl silicone oil, had a great effect on the properties of composites. The mechanical properties, thermal conductivity, dielectric strength and volume resistivity of SiO2-s-Si(OCH3)3/silicone rubber composites were considerably higher than that of pristine SiO2/silicone rubber composites at the same content of SiO2, while the dielectric constant and dielectric loss tangent of SiO2-s-Si(OCH3)3/silicone rubber composites was lower than that of pristine SiO2/silicone rubber composites at the same content of SiO2.

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To ensure the smooth insertion of the side rod/fiber bundle during the three-dimensional woven preform contour locking process, the influence of the diameter, speed, and other parameters on the free end vibration displacement response of the side rod and the fiber-carrying needle is analyzed. By calculating the kinetic energy and potential energy of the two separately, the dynamic equations of the side rod and the fiber-carrying needle are established based on Hamilton's principle and discretized. The state equations are solved using the Runge–Kutta method, and the free end vibration displacement responses of the side rod and the fiber-carrying needle for different parameters are obtained. The results show that the equilibrium position and the maximum amplitude of the free end of the side rod and the fiber-carrying needle decrease with the increase of the section diameter and the decrease of the axial speed. And the circular tube wall thickness has less impact on the free end vibration displacement of the fiber-carrying needle. The overall analysis shows that the fiber-carrying needle vibration response is smaller than that of the side rod under the same parameters.