异形截面复合材料构件成形及力学性能预测方法研究

The component formed by flexible guide 3D weaving technology has excellent interlayer performance and have been widely used. But it is restricted by the path planning and forming process, resulting in long weaving time and unstable component performance. At the same time, it is formidable to accurately form special-section components using the traditional process due to the complexity, and the lack of corresponding prediction methods for mechanical properties seriously hinders the application of 3D weaving technology in special-section components. In this paper, the weaving mechanism of flexible guided three-dimensional weaving technology is deeply explored, and the process scheme of sub-regional weaving is proposed. The section shape is approximated by piecewise fitting, which effectively solves the problem of forming complex irregular section components. Based on this process scheme, the macro-and meso-scale finite element mechanical properties prediction model of traction rod is established, and the stress state of traction rod under axial load is analyzed by taking the meso-scale prediction results as material properties. The fiber volume fraction model was further established to analyze the relationship between the fiber volume fraction in XY direction and the mechanical properties, which laid the foundation for the shape control of the weaving process. The experimental results show that the error of finite element prediction of Z-direction elastic modulus is less than 4.2 %, which provides the basis for the early design and engineering application of special-shaped section members.