单向碳纤维复合材料界面力学性能测试研究

Experimental Study on Interface Mechanical Properties of Unidirectional Carbon Fiber Composites

编织陶瓷基复合材料由于复杂的纤维编织结构,其界面力学性能测试与表征较困难。为了研究编织复合材料的界面力学性能,探明应力作用下的界面失效机制,本文设计并制备了单向模型复合材料,开展相关单纤维压出的微纳实验。结果表明,C/SiC采用PyC界面时,其界面剪切强度约为35 MPa。通过对纤维的压出过程进行分析,揭示了载荷作用下的裂纹萌生及扩展规律。课题研究不仅对拓展复合材料的应用具有重要的经济意义,而且可为复合材料界面力学与断裂力学的研究提供一定的理论和实验支撑。

The weaved ceramic matrix composites are difficult to characterize the interface mechanical properties due to the complex fiber braid structure.In order to investigate the interface mechanical properties of braided composites and explore the interface failure mechanism under stress,a one-way model composite was designed and fabricated,and the microstructure-nano experiment of single fiber extrusion was carried out.The results show that when adopting PyC interface in C/SiC,the interfacial shear strength is about 35 MPa.Through the analysis of the fiber extrusion process,the crack initiation and propagation law under load is revealed.The present results not only have important economic significance for applying composite materials,but also provides theoretical and experimental support for studying interface mechanics and fracture mechanics of composite materials.