ZrB2 改性C/ C-SiC 复合材料性能研究

采用碳纤维复合网胎针刺预制体,通过溶液浸渍工艺制备了碳纤维增强C/C-SiC和C/C-SiC-ZrB2陶瓷基复合材料,并对材料的力学、热物理和烧蚀性能进行了分析对比。结果表明:针刺C/C-SiC-ZrB2复合材料的面内弯曲强度、厚度方向的压缩强度、层间剪切强度分别为199、274和19.3 MPa,各性能均低于对应的针刺C/C-SiC复合材料。针刺C/C-SiC-ZrB2材料与针刺C/C-SiC材料相比,热导率得到大幅度提高,而线胀系数略微有所降低。2 500 K、600 s风洞试验后,针刺C/C-SiC-ZrB2复合材料表现出良好的抗氧化烧蚀性能,质量烧蚀率约0.4×10-4g/s。

Effect of ZrB2 on Properties of C/ C-SiC Composites

Carbon fiber needling preform reinforced C/ C-SiC composites and C/ C-SiC-ZrB2 composites were
prepared by liquor dipping process. The mechanical, thermal and ablation properties of the composites were investigated
and compared. The results show that the flexural strength,compress strength and shear strength of the C/ C-SiCZrB2
composite are 199 MPa, 274 MPa and 19. 3 MPa respectively. These mechanical properties of the C/ C-SiCZrB2
composite are all lower than the counterpart properties of C/ C-SiC composite. Compared with C/ C-SiC composite,
thermal conductivity of the C/ C-SiC-ZrB2 is greatly higher and the linear expansion coefficient of the C/ C-SiCZrB2
composite is slightly lower. The ablation behavior of them is studied by arc wind tunnel test at a temperature of 2
500 K for 600 s. The C/ C-SiC-ZrB2 composite has an average mass ablation rate of 0. 4×10-4 g/ s and has excellent
properties of oxidation resistance and ablation resistance.