基于纱线真实形态的三维机织复合材料细观结构及其厚度计算

如何确定预制件的结构参数与复合材料厚度之间的数量关系是设计人员面临的一个难题。对三维机织复合材料横截面图像细观结构进行观察分析。结果表明,决定三维机织复合材料厚度的部位在沿纬纱的中心线横截面处;经纱的横截面呈长方形;纬纱的纵向轨迹呈直线形。基于细观结构导出了用预制件结构设计参数表示的复合材料厚度计算公式,用算例验证了公式的正确性。验证结果表明,复合材料厚度计算公式正确,具有实用性。

MICROSTRUCTURE AND THICKNESS EQUATION OF 3D WOVEN COMPOSITES BASED ON YARN’S TRUE CONFIGURATION

There is a difficult problem for composites designers to solve; that is, how to confirm the relationship between preform structural design parameters and composites thickness. Based on observing and analyzing digital images and microstructure of 3D woven composites cross sections, the results show that the position of deciding the thickness of 3D woven composites is located at the cross section which passes through the center of the weft thread, the cross-section of a warp thread is rectangular, and the longitudinal track of a weft thread is linear. Furthermore. thickness equations for 3D woven composites are deduced, which are expressed by preform structural design parameters. In the end, an example is given to certify the validity of the thickness equations. The result shows that the thickness equations are correct and practical.