Jiang Li-Li, Li Zhen-Guo, Wang Dong-Ye, Zhai Jun-Jun, Kong Xiang-Xia
College of Civil Engineering and Architecture, Xiamen City University, Xiamen 361008, China.
College of Aeronautics and Astronautics, North China Institute of Aerospace Engineering, Langfang 065000, China.
Polymers (Basel). 2024 Apr 21;16(8):1166. doi: 10.3390/polym16081166.
A three-dimensional helix geometry unit cell is established to simulate the complex spatial configuration of 3D braided composites. Initially, different types of yarn factors, such as yarn path, cross-sectional shape, properties, and braid direction, are explained. Then, the multiphase finite element method is used to develop a new theoretical calculation procedure based on the unit cell for predicting the impacts of environmental temperature on the thermophysical properties of 3D four-direction carbon/epoxy braided composites. The changing rule and distribution characteristics of the thermophysical properties for 3D four-direction carbon/epoxy braided composites are obtained at temperatures ranging from room temperature to 200 °C. The influences of environmental temperature on the coefficients of thermal expansion (CTE) and the coefficients of thermal conduction (CTC) are evaluated, by which some important conclusions are drawn. A comparison is conducted between theoretical and experimental results, revealing that variations in temperature exert a notable influence on the thermophysical characteristics of 3D four-directional carbon/epoxy braided composites. The theoretical calculation procedure is an effective tool for the mechanical property analysis of composite materials with complex geometries.
建立了三维螺旋几何单胞来模拟三维编织复合材料的复杂空间构型。首先，解释了不同类型的纱线因素，如纱线路径、横截面形状、性能和编织方向。然后，采用多相有限元方法，基于该单胞开发了一种新的理论计算程序，用于预测环境温度对三维四向碳/环氧编织复合材料热物理性能的影响。获得了三维四向碳/环氧编织复合材料在室温至200℃温度范围内热物理性能的变化规律和分布特征。评估了环境温度对热膨胀系数（CTE）和热传导系数（CTC）的影响，据此得出了一些重要结论。对理论结果和实验结果进行了比较，结果表明温度变化对三维四向碳/环氧编织复合材料的热物理特性有显著影响。该理论计算程序是分析具有复杂几何形状的复合材料力学性能的有效工具。
