短切碳纤维增强塑料纤维分布的精细化表征

FINE CHARACTERIZATION OF THE FIBER DISTRIBUTION OF SHORT CARBON FIBER REINFORCED PLASTIC

碳纤维增强塑料是近几年新兴的优质轻质材料,具有较好的力学性能,被广泛应用于汽车、电子等行业中。短切碳纤维增强塑料通常采用注塑成型工艺,其性能与纤维分布有着密切的关系。为了加深对短切碳纤维增强注塑件内部纤维分布规律的了解,开展SEM和X射线断层扫描试验,结合图像处理技术得到纤维拔出孔直径、流动平面纤维投影长度以及纤维取向分布规律,并与Moldex模拟结果对比,进一步验证纤维取向分布的规律。结果表明:碳纤维增强塑料成型后纤维拔出孔直径的分布受纤维含量的影响不大;纤维取向整体朝向为流动方向,沿流动方向的取向概率随平面到芯层距离的减小先增大后下降;碳纤维增强塑料注塑成型时,沿流动方向取向比例较高的区域均为位于皮层和芯层的中间区域。

Carbon fiber reinforced plastic is a new high-quality lightweight material in recent years.It has good mechanical properties and is widely used in the automotive,electronics and other industries.Short carbon fiber reinforced plastics are usually injection molded and their properties are closely related to fiber distribution.In order to deepen the understanding of the internal fiber distribution of staple fiber carbon fiber reinforced plastics,SEM and X-ray tomography tests were carried out.The fiber extraction hole diameter,the projected length of the flow plane fiber and the distribution of fiber orientation were obtained by image processing technology,and the law of fiber orientation distribution was further verified by comparison with the Moldex simulation results.The results show that the fiber extraction hole diameter distribution of carbon fiber reinforced plastics is not affected by the fiber content.The overall orientation of fiber orientation is the flow direction,and the orientation probability along the flow direction increases first and then decreases with the decrease of the distance from the plane to the core layer.In the case of carbon fiber reinforced plastic injection molding,the areas with a higher orientation ratio in the flow direction are located in the middle of the skin layer and the core layer.