在变后对AA2124/SiC金属矩阵复合材料进行机械和微结构研究
Agnieszka Rutecka1, Katarzyna Makowska2, Zbigniew Ludwik Kowalewski3
1Faculty of Civil Engineering, Warsaw University of Technology, Al. Armii Ludowej 16, 00-637 Warsaw, Poland.
Materials (Basel, Switzerland)
|October 16, 2025
概括
带有碳化 (SiC) 增强的金属矩阵复合材料 (MMC) 在300°C时表现出高应力灵敏度. 微小的压力变化会导致快速失败,突出了关键值的压力行为.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 金工业是金工业的一个方面.
背景情况:
- 金属矩阵复合材料 (MMCs) 是具有增强性能的先进材料.
- 用碳化 (SiC) 增强的合金AA2124用于苛刻的应用.
- 了解高温时的爬行行为对于结构完整性至关重要.
研究的目的:
- 为了研究AA2124/SiC金属矩阵复合材料在300°C的拉伸爬行行为.
- 为了确定SiC颗粒大小和含量对爬行性能的影响.
- 识别值压力水平并了解相关的损害机制.
主要方法:
- 拉伸式爬行测试是在各种恒定应力下在300°C下进行的.
- 使用扫描电子显微镜 (SEM) 进行了微结构分析.
- 在SiC增强中,颗粒大小 (3微米,0.6微米) 和体积分数 (17%,25%) 都有所不同.
主要成果:
- 在狭窄的压力范围内观察到高压力敏感性.
- 确定了值应力值:较大的SiC颗粒/含量较低的~5MPa,其他~1MPa.
- 微观结构观测揭示了空隙形成及其对机械反应和断裂的影响.
结论:
- 在AA2124/SiC复合材料中存在一个临界值应力,超过这个值后,变会显著加快.
- 即使在这个值附近的微小应力波动也会导致材料在高温下快速降解和结构故障.
- 空洞演化是一个关键的损伤机制,影响这些MMC的爬行性能和断裂行为.
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