三维全五向编织复合材料细观结构实验分析

对三维(3D)全五向编织复合材料的细观结构进行了实验研究,三维全五向编织复合材料是一种新型的编织复合材料,其细观结构对预测材料的性能有重要作用。采用显微计算机断层成像(micro-CT)技术得到了三维全五向编织复合材料的截面图片,通过在碳纤维试件中混编入少量玻璃纤维作为示踪纱,提高了示踪纤维束在截面图片中的的对比度。并通过三维重建得到纤维束实体模型,结合CAD技术对纤维束的横截面形状与空间走向进行了研究。结果表明:编织纱与轴纱纤维束的截面形状在材料不同区域与不同的花节高度内是变化的;在不同区域,编织纱的空间走向也是不同的;而轴纱在空间上基本保持伸直。由于编织纱对轴纱的挤压使轴纱表面产生螺旋状的压痕。

Experimental analysis on micro-structure of three-dimensional full five-directional braided composites

The micro-structure of three-dimensional (3D) full five-directional braided composite is investigated.Three-dimensional full five-directional braided composite is a new kind of braided composite. The micro-structure plays an important role in predicting performance of the material. Micro-computed tomography (micro-CT) is used to get the cross-section images of the three-dimensional full five-directional braided composites. Glass fiber as tracer yarns is mixed into the sample made of carbon fiber to improve its contrast in the images. The solid model of tracer yarns created by 3D reconstruction with these images is used to study the cross-sections and orientations of the fiber tows through CAD technology. The results show that the cross-sections of braiding yarns and axial yarns change with the regions and the heights in one pitch of the material; the spatial orientations of braiding yarns are not the same in different regions. The axial yarns are almost straightened in space. The surface of the axial yarns has helical indentation because of the extrusion of braiding yarns on axial yarns.