化学学报 ›› 2009, Vol. 67 ›› Issue (23): 2750-2754. 上一篇    下一篇

研究论文

先驱体转化法制备高性能Si-B-N陶瓷纤维

唐云,王军,李效东,李文华,王小宙,王浩   

  1. (国防科技大学新型陶瓷纤维及其复合材料国防科技重点实验室 长沙 410073)
  • 投稿日期:2008-12-02 修回日期:2009-04-28 发布日期:2009-06-15
  • 通讯作者: 唐云 E-mail:tangyunkd@gmail.com
  • 基金资助:

    国防基础科研项目(No.A2820060068);国家高技术研究发展(863)计划(No. 2006AA03217);国家自然科学基金(No. 50702075;50802113)

Preparation of High Performance Si-B-N Ceramic Fibers by Polymer Derived Method

Tang, Yun*,Wang, Jun,Li, Xiaodong,Li, Wenhua,Wang, Xiaozhou,Wang, Hao   

  1. (State Key Laboratory of Advanced Ceramic Fibers & Composites, National University of Defense Technology, Changsha 410073)
  • Received:2008-12-02 Revised:2009-04-28 Published:2009-06-15

以聚硼硅氮烷为先驱体, 经熔融纺丝、不熔化处理以及在氨气气氛中高温裂解制备了Si-B-N陶瓷纤维. 利用元素分析、FTIR、XRD、SEM和波导法等对纤维的组成结构和性能进行了表征. 结果表明: Si-B-N纤维的组成为Si1.13BN2.47, 室温下纤维的抗拉强度为1.8 GPa, 弹性模量为196 GPa; 纤维具有很好的高温稳定性, 在惰性气氛中可以保持非晶状态至1700 ℃, 加热至1850 ℃结晶, 形成Si3N4和BN等相. 同时, 纤维表现出优良的介电性能, 室温下, 在测试频率为2~18 GHz时, 其平均介电常数和介电损耗角正切值分别为3.68和0.0042. 该纤维有望成为新型耐高温透波复合材料的候选增强材料.

关键词: Si-B-N陶瓷纤维, 先驱体转化法, 聚硼硅氮烷, 透波纤维, 耐高温

Si-B-N ceramic fibers with composition Si1.13BN2.47 were prepared by melt-spinning, curing and pyrolysis of a preceramic polyborosilazane. The composition, structure and properties of the fibers were characterized by elemental analysis, FT-IR, X-ray diffraction, SEM and wave-guide methods. The fibers show good room temperature mechanical properties. The average tensile strength (σ) and elastic modulus (E) of Si-B-N fibers is 1.8 and 196 GPa, respectively. They also exhibit excellent high temperature resistance and remain amorphous up to 1700 ℃ in inert atmospheres. A mixture of Si3N4 and BN crystalline phases was observed upon heating to 1850 ℃. In addition, the obtained fibers show good dielectric properties according to the measurement by a wave-guide technique. The average dielectric constant (ε) and loss tangent (tan δ) of the as-obtained fibers are about 3.68 and 0.0042 in 2~18 GHz, respectively. Such performance characteristics make the Si-B-N fiber promising candidate as reinforcement for application to high temperature radar-wave transparent composite materials.

Key words: Si-B-N ceramic fiber, polymer derived method, polyborosilazane, wave-transparent fiber, high temperature resistance