准三维C/C复合材料的弯曲性能及其破坏机理

以碳纤维针刺毡为预制体,采用CVI法或结合液相法制备了热解碳、树脂碳和沥青碳基质的准三维C/C复合材料,并研究了这些材料的弯曲性能及其断裂机理.研究表明:对于热解碳基质,SL基质碳的弯曲强度明显高于RL和SL RL两种基质碳;弯曲强度随密度增高而增大;致密度越高,基体支撑越强,同时微裂纹和孔隙度越低,弯曲性能越好.

Bending Property and Fracture Mechanism of Quasi-3D C/C Composites

Using needled-carbon fiber felts as perform,quasi-3D C/C composites with pyrolytic carbon(PyC),or/and resin carbon,pitch carbon as matrix,respectively,were fabricated by chemical vapor infiltration method or/and liquid method.In the present paper,the bending property and fracture mechanism of these composites were investigated.The results showed that,the bending strength of the C/C composites with smooth laminar(SL) structural PyC matrix is obviously higher than those with rough laminar(RL) or SL RL PyC matrix;the bending strength increase with the increasing of density of C/C composites;the higher the densification,the stronger the matrix reinforcement and the bending property.