陶矩阵复合材料在氧化乙烯火下循环废弃行为
Hailang Ge1,2, Xianqing Chen2, Guangyu Li1
1College of Mechanical and Electrical Engineering, Suqian University, Suqian 223800, China.
Materials (Basel, Switzerland)
|September 28, 2024
概括
碳化 (SiC/SiC) 复合材料的循环废除显示了较低的质量损失,但比单次废除更高的线性废除率. 表面氧化物和二氧化颗粒抵御剥离,尽管热冲击会导致裂纹.
科学领域:
- 材料科学 材料科学 材料科学
- 陶复合材料 陶复合材料
背景情况:
- 碳化 (SiC/SiC) 复合材料是用于高温应用的先进材料.
- 了解除行为对于它们在极端环境中的部署至关重要.
研究的目的:
- 调查和比较单一和循环废弃条件下的平面编织SiC/SiC复合材料的废弃性.
- 分析微观结构的变化,并确定负责材料降解和抗性的机制.
主要方法:
- 在平面编织的SiC/SiC复合材料上使用氧化乙烯火进行了废弃试验.
- 采用宏观和微观结构特征技术来检查废弃的表面和内部结构.
主要成果:
- 循环切除导致较低的质量切除率,但与单次切除相比,线性切除率更高.
- 表面分析显示,在剥离中心形成了富含氧化物的白色氧化物.
- 中部地区的纤维显示层次的剥离,具有尖的形态和附着的二氧化颗粒.
- 化氧化物和二氧化颗粒有助于增强废弃性.
结论:
- 保护性氧化物层的形成和化颗粒的存在减轻了剥离损伤.
- 在周期性除过程中引起的热冲击会导致SiC/SiC复合材料的裂.
- 这些发现为应用SiC/SiC复合材料在具有复杂热冲击和剥离的环境中提供了洞察力.
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