通过有序氧复合物提高高合金的强度和可塑性
Zhifeng Lei1, Xiongjun Liu1, Yuan Wu1
1Beijing Advanced Innovation Center for Materials Genome Engineering, State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing, China.
Nature
|November 16, 2018
概括
氧现在可以在高合金 (HEAs) 中同时提高金属的强度和可塑性. 这项研究揭示了有序的氧化复合体,
科学领域:
- 材料科学
- 金属工程
- 固态化学
背景情况:
- 氧气通常是金属中的间接杂质,导致脆性.
- 使用氧气强化金属的传统方法导致柔性丧失.
- 高合金 (HEAs) 提供了一个探索新增强化机制的独特平台.
研究的目的:
- 研究高合金中有序氧复合物的形成和作用.
- 确定这些复合物是否可以同时增强强度和柔性.
- 阐明这些有序氧复合体介导的强化机制.
主要方法:
- 一个模型TiZrHfNbHEA与2.0原子百分比的氧气.
- 使用纳米尺度成像和分析对氧复合物的表征.
- 拉力测试用于评估机械性能 (强度和可塑性).
- 对位行为和变形机制的分析.
主要成果:
- 在HEA矩阵中形成有序的纳米氧复合体.
- 在氧化HEA中显著增强拉伸强度 (48.5%) 和延展性 (95.2%).
- 观察到长期存在的强度-柔性权衡的破坏.
- 鉴定了一种新的应变硬化机制,涉及到脱位剪切模式和乘法变化.
结论:
- 排序氧复合体代表了HEAs中间歇氧的新状态.
- 这种新的复杂结构同时增强了强度和性, 克服了以前的局限性.
- 这些发现为设计先进的金属材料,特别是含有Ti,Zr和Hf的材料提供了新的策略.
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