在室温下,纳米晶体铜的超塑性伸展性在室温下
1State Key Laboratory for Rapidly Solidified Non-equilibrium Alloys, Laboratory for Atomic Imaging of Solids, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110015, People's Republic of China.
Science (New York, N.Y.)
|February 26, 2000
概括
高纯度的纳米晶体铜表现出超过5000%的极端伸展性,这是由于谷物边界活动而不是失位. 这一发现为先进的材料科学和技术开辟了新的途径.
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.
- 纳米技术 纳米技术
背景情况:
- 纳米晶体 (nc) 材料由于其小粒度而具有独特的特性.
- 纯铜是一种广泛使用的金属,具有增强机械性能的潜力.
研究的目的:
- 为了合成大量的纳米晶体纯铜.
- 为了研究这种nc铜的机械行为,特别是可扩展性.
- 阐明对观察到的特性负责的潜在变形机制.
主要方法:
- 用于合成散装纳米晶体纯铜的电解.
- 在室温下滚动以评估机械性能.
- 微结构分析以确定变形机制.
- 在室温下进行拉伸式爬行研究.
主要成果:
- 成功合成了高纯度,高密度的散装纳米晶体铜.
- 在室温滚动过程中观察到超过5000%的极端伸展性,没有应变硬化.
- 微观结构和爬行研究表明,由谷物边界活动主导的变形.
结论:
- 颗粒边界活动是这种纳米晶体铜中超塑性扩展的主要机制.
- 观察到的行为证明了纳米晶体材料在科学和技术应用中的巨大潜力.
- 这项研究突出了推动NC材料的新可能性.
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