具有高柔性强度的连续SiC骨架增强反应结合的碳化物复合材料
Qian Xia1, Shihao Sun1, Jun Ye1
1Institute of Advanced Ceramics, School of Materials Science and Engineering, Northeastern University, Shenyang 110004, China.
Materials (Basel, Switzerland)
|July 29, 2023
概括
这项研究增强了使用分散碳黑 (CB) 和聚乙烯胺 (PEI) 的反应结合化碳 (RBBC) 复合材料. 这种方法提高了碳化-SiC陶的机械性能,如曲强度和断裂性.
科学领域:
- 材料科学 材料科学 材料科学
- 陶工程 陶工程
- 复合材料 复合材料 复合材料
背景情况:
- 反应结合碳化 (RBBC) 复合材料为各种应用提供了具有成本效益的网状烧结.
- 虽然研究了微观结构和反应机制,但RBBC复合材料的强化机制仍然不清楚.
- 优化RBBC属性需要了解添加剂和处理参数的作用.
研究的目的:
- 通过控制微观结构来研究RBBC复合材料的强化机制.
- 通过优化加工,提高碳化-SiC复合材料的机械性能.
- 阐明碳黑 (CB) 和聚乙烯胺 (PEI) 在RBBC形成中的作用.
主要方法:
- 通过B4C-C预成型的液 (Si) 透制造密集的碳化物陶.
- 使用分散碳黑 (CB) 作为碳来源和聚乙烯胺 (PEI) 作为分散剂.
- 分析微观结构,反应路径和机械性能增强.
主要成果:
- 由于与化Si过度反应而受到CB保护的碳化物颗粒的均分布.
- 在SiC颗粒的现场形成导致了连续的碳化-SiC陶骨架.
- 观察到显著的改善:屈曲强度 (470 MPa, +44%),断裂性 (4.6 MPa·m1/2, +15%),以及维克尔硬度 (22 GPa, +10%).
结论:
- 使用PEI分散的CB有效控制反应和微观结构,从而提高RBBC复合材料的机械性能.
- 一个连续的碳化-SiC骨架的形成是观察到的加强的关键.
- 这种方法为生产高性能RBBC材料提供了可行的途径.
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