通过添加Cr来定制Al-7Si-0.35Mg-0.35Fe合金的微观结构和机械性能:关于富含铁的相变修饰的研究
Chiteng Le1, Wenjun Liu1, Tiancai Yin1
1College of Materials Science and Engineering, Chongqing University of Technology, Chongqing 400054, China.
Materials (Basel, Switzerland)
|February 13, 2026
概括
将 (Cr) 添加到高铁合金中,可以改进微观结构,并将有害的针状富含铁的相转化为有益的块状相. 这大大增强了合金的性能.
科学领域:
- 材料科学 材料科学 材料科学
- 金工业是一种金工业.
- 合金开发 合金开发
背景情况:
- 合金中的富含铁的金属间化合物,特别是回收的金属间化合物,具有有害的针状形态.
- 这些阶段会破坏矩阵,降低机械性能,并限制回收的使用.
研究的目的:
- 研究 (Cr) 添加对Al-7Si-0.35Mg-0.35Fe合金微观结构和机械性能的影响.
- 修改富含铁的阶段的形态,并提高合金的整体性能.
主要方法:
- 在Al-7Si-0.35Mg-0.35Fe合金中系统添加Cr (0-0.25重量%)
- 微观结构分析,观察二级树突臂间距的变化和富含铁的阶段形态.
- 机械性能测试 (抗拉强度,延伸) 用于评估合金性能.
主要成果:
- 加Cr完善了二级树石臂间距.
- 富含铁的相从针状的β-Al5FeSi转化为块状的α-Al15(Fe,Cr) 3Si2.2.
- 0.20Cr合金显示,富含铁的相球性增加了65%,相当直径减少了84%.
- 确定最佳的Cr添加范围为0.05-0.20重量%以改善形态.
- 与没有Cr的合金相比,0.20Cr合金的最终抗拉强度增加了19%,延伸度增加了107%.
结论:
- 有效地改变了高铁合金中富含铁的阶段的形态.
- 改进的富含铁的相位形态导致显著增强的机械性能,包括拉伸强度和柔性.
- 这项研究提供了一个可行的策略,以提高合金的质量和可回收性.
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