Structural mass irregularities and fiber volume influence on morphology and mechanical properties of unsaturated polyester resin in matrix composites

This paper presents the comparative results of a current study on unsaturated polyester resin (UPR) matrix composites processed by filament winding method, with cotton spun yarn of different mass irregularities and two different volume fractions. Physical and mechanical properties were measured, namely ultimate stress, stiffness, elongation%. The mechanical properties of the composites increased significantly with the increase in the fiber volume fraction in agreement with the Counto model. Mass irregularities in the yarn structure were quantitatively measured and visualized by scanning electron microscopy (SEM). Mass irregularities cause marked decrease in relative strength about 25% and 33% which increases with fiber volume fraction. Ultimate stress and stiffness increases with fiber volume fraction and is always higher for yarn with less mass irregularities.

本文介绍了一项关于采用纤维缠绕法加工的不饱和聚酯树脂（UPR）基复合材料的对比研究结果，该研究使用了具有不同质量不匀率的棉纺纱线以及两种不同的体积分数。对物理和机械性能进行了测量，即极限应力、刚度、伸长率。复合材料的机械性能随着纤维体积分数的增加而显著提高，这与康托模型相符。通过扫描电子显微镜（SEM）对纱线结构中的质量不匀率进行了定量测量和可视化。质量不匀率导致相对强度显著下降，约为25%和33%，且随着纤维体积分数的增加而增大。极限应力和刚度随着纤维体积分数的增加而增大，并且质量不匀率较低的纱线的极限应力和刚度总是更高。