Effect of carbon fiber layers on braiding properties during three-dimensional weaving

Abstract

Carbon fiber composites are widely used in aerospace, rail transportation, and other fields. In the three-dimensional weaving process of carbon fiber preforms, the collision and dislocation of weaving needle and guide bar caused by the deformation of guide bar directly affect the normal operation of weaving process. In order to improve the precast precision and quality, this paper intends to study the deformation mechanism of the outermost guide rod by combining theory and experiment. Based on statically indestructible beam theory, a mathematical model of the influence of the number of weaving layers on the deflection of the guide bar was established, and the influence of the number of weaving layers on the value range of the weaving region and the influence of the transverse precision of the precast was obtained. With the increase of weaving layers, the needle feeding range gradually decreases, the compacted layer is 100 layers compared with 20 layers, and the injection interval is reduced by 20.93%. When the compacted layer is 60 layers, the range of needle insertion decreases rapidly with the increase of the number of layers in each step. Compared with the 10 layers in each step, the range of needle insertion decreases 30.54% when the number of layers in each step is 25 layers, and it is better to control the number of layers in each step within 20 layers. When weaving 120 layers in different steps, the average deviation between the theoretical and experimental values of transverse accuracy is 5.06%, which verifies the correctness of the theoretical calculation. It provides a theoretical basis for the design of fiber prefabricated fabric weaving equipment and the improvement of weaving technology.