造Al-Si合金中的致命缺陷是由于添加了Sn
Yao Xiao1, Jicheng Wang2, Qianyu Deng2
1State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China.
Materials (Basel, Switzerland)
|September 9, 2023
概括
将锡 (Sn) 添加到- (Al-Si) 合金中,会产生无形的氧化物. 这些氧化物捕获融化,导致毛孔和裂收缩,在造状态下显著降低机械性能.
科学领域:
- 材料科学 材料科学 材料科学
- 金工业是金工业的一个方面.
- 造技术 造技术 造技术
背景情况:
- 造缺陷在造合金中普遍存在,对机械性能产生负面影响.
- 消除缺陷通常需要变形,这可能是不受欢迎的.
- 合金元素可以影响造缺陷的形成和严重程度.
研究的目的:
- 研究 (Sn) 添加对- (Al-Si) 合金机械性能的有害影响.
- 了解对Sn.引起的财产退化负责的微观结构机制.
主要方法:
- 利用3D计算机断层扫描进行微观结构分析.
- 使用扫描电子显微镜 (SEM) 和传输电子显微镜 (TEM) 进行详细的成像.
- 研究了氧化的作用及其与膜的相互作用.
主要成果:
- 发现无形的氧化物,与膜相关,并作为封装.
- 通过含有Sn的外观察到融的捕获,在凝固过程中增加了收缩孔隙.
- 识别了裂的启动和沿毛孔和脆性氧化物传播.
结论:
- 添加锡显著降低了Al-Si合金的机械性能.
- 无形氧化的形成和随后的多孔性是物质降解的关键机制.
- 建议避免在用于造应用的Al合金中添加Sn.
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