碳纤维/环氧预浸料摩擦滑移特性测试及其变化规律

Measurement and evolution of frictional slipping behavior of carbon fiber/epoxy prepreg

带曲率的复合材料层合结构在制备过程中,预浸料铺层之间、预浸料铺层与模具之间会发生摩擦滑移行为,其滑移程度影响复合材料的制造质量。本文采用自行建立的预浸料摩擦滑移特性测试装置,针对碳纤维/环氧树脂预浸料体系,测试分析了不同工艺条件下,预浸料铺层与铺层之间,以及预浸料铺层与钢模具、铝模具和橡胶模具材料之间的摩擦滑移特性。实验结果表明,温度变化会改变预浸料铺层间的摩擦机制,而外压变化不改变预浸料铺层间的摩擦机制;较高的温度或较小的外加压力会减小预浸料铺层的摩擦阻力,有利于预浸料铺层的滑移运动;预浸料铺层与模具材料之间的摩擦滑移特性与模具材料的表面粗糙度有关,其摩擦阻力受温度影响更明显,而受外压影响变化较小。

During fabricating curved composite laminate, frictional slipping processes in prepreg stack and between prepreg and mold occur. The slipping degree has significant effect on the manufacturing quality of composite. In this paper, a testing device was established to evaluate the frictional slipping behavior of prepreg systems. By means of this equipment, the frictional resistances of carbon fiber/epoxy prepreg and prepreg and prepreg and tool materials, including steel, aluminum and rubber, under different processing parameters were analyzed. The experimeantal results indicate that the change of temperature can alter the frictional mechanism in prepreg stack, while the variation of exteral pressure does not change the frictional mechanism in prepreg stack. High temperature and low external pressure decrease the frictional resistance in prepreg stack, and further the slipping behavior. In addition, the surface roughness of tool material has great effect on the rictional slipping property between prepreg and tool, and the frictional resistance is influenced by the temperature rather than the external pressure.