EFFECT OF PYROLYSIS PROCESSES ON THE MICROSTRUCTURE AND MECHANICAL PROPERTIES OF Cf/SiC COMPOSITES FABRICATED BY PRECURSOR PYROLYSIS
-
摘要: 以聚碳硅烷(PCS)/二乙烯基苯(DVB)为先驱体,经8个周期的反复真空浸渍-交联-裂解处理制备出三维编织碳纤维增强碳化硅(3D-B Cf/SiC)复合材料,考察了裂解工艺对材料结构与性能的影响。结果表明:提高裂解升温速率可以提高材料密度,形成较理想的界面结合,从而提高材料的力学性能。裂解温度对材料性能也有较大的影响,Cf/SiC复合材料在第6个周期采用1600℃ 裂解可以弱化纤维与基体之间的界面,提高材料致密度,材料的力学性能也得到较大改善。裂解升温速率为15℃/min,第6个周期采用1600℃裂解制备的Cf/SiC材料性能较好,弯曲强度达到556.7 MPa。Abstract: Three-dimensionally braided carbon fiber reinforced SiC(3D-B Cf/SiC) composites were fabricated through 8 cycles of vacuum infiltration of polycarbosilane(PCS)/divinylbenzene(DVB) and subsequent pyrolysis under an inert atmosphere. The effects of pyrolysis processes on the microstructure and mechanical properties of Cf/SiC composites were investigated. The results show that increasing heating rates can increase the density and result in better interfacial bonding leading to better properties of Cf/SiC composites. At the same time, one cycle of 1600℃ heat treatment could also increase the density and mechanical properties of Cf/SiC composites. It was found that the flexural strength of the Cf/SiC composites after pyrolysis by 15℃/min and one cycle of 1600°C heat treatment reached 556.7 MPa.
-
Key words:
- Cf/SiC composites /
- pyrolysis temperatures /
- heating rates /
- flexural strength /
- interface /
- density
点击查看大图
计量
- 文章访问数: 1827
- PDF下载量: 850
- 被引次数: 0