111)/6H-SiC接口的机械和电子特性:一个DFT研究
Mostafa Fathalian1, Eligiusz Postek1, Tomasz Sadowski2
1Institute of Fundamental Technological Research, Polish Academy of Sciences, Pawińskiego 5B, 02-106 Warsaw, Poland.
Molecules (Basel, Switzerland)
|June 10, 2023
概括
使用密度函数理论 (DFT) 研究 (Al) /碳化 (SiC) 复合材料中的空隙,发现空隙,特别是在SiC方面,增强拉伸性能和断裂性. 所有的职位空缺都显示出最小的影响.
科学领域:
- 材料科学 材料科学 材料科学
- 计算材料科学科学 计算材料科学
- 固态物理 固态物理
背景情况:
- (Al) /碳化 (SiC) 复合材料在各种工程应用中至关重要.
- 了解界面行为和缺陷效应是优化材料性能的关键.
- 密度函数理论 (DFT) 提供了一种强大的计算方法,用于在原子水平上研究材料特性.
研究的目的:
- 调查职位空缺对Al111/6H SiC复合材料的机械和电子性能的影响.
- 模拟和分析C端和Si端接口配置.
- 为了确定这些复合材料的界面断裂性和抗拉强度.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 开发了具有C端和Si端接口的超级晶格模型.
- 拉力强度是通过拉伸超级电池来评估的,折断度是使用扬模和表面能量来计算的.
主要成果:
- C和Si空位降低了接口粘附力,而Al空位的影响是可以忽略不计的.
- 缺口的存在,特别是在SiC方面,改善了复合材料的拉伸性能.
- 对于C端接口,模量较高,表面能量显著影响断裂性.
结论:
- 可以利用空隙调整Al/SiC复合材料的机械性能.
- 该研究提供了关于接口终结和缺陷对材料性能作用的见解.
- DFT计算是预测复合行为的实验方法的可行替代方案.
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