ナノ構造の金属の高張力柔軟性

Yinmin Wang¹, Mingwei Chen, Fenghua Zhou

¹Department of Materials Science and Engineering, The Johns Hopkins University, Baltimore, Maryland 21218, USA.

Nature

|November 1, 2002

まとめ

研究者らは,銅の新たな熱力学的処理を開発し,バイモダルの粒子の構造を生み出しました. このアプローチは,ナノ結晶金属の伸縮性を著しく高め,その実用的な応用を改善します.

科学分野:

マテリアルサイエンス材料科学
メタルルジーは,金属の製造業です.
ナノテクノロジーナノテクノロジー

背景:

ナノ結晶金属 (粒径<100 nm) は,粗粒または合金金属と比較して優れた強度を示します.
しかし,それらの実用的な応用は,室温での低張力柔性によって制限されています.
純粋なナノ結晶銅は,高い強度 (>400 MPa) を示しているが,故障までの延伸は限られている.

研究の目的:

高強度を維持しながら,張力柔性性を改善するために,銅の熱機械処理を開発する.
バイモダルの粒子の大きさの分布が機械的性質に与える影響を調査する.
ナノ構造の金属の実用的な応用を可能にする.

主な方法:

銅に新しい熱力学的処理が施された.
この処理により,ナノ結晶/超微細 (<300 nm) マトリックス内のマイクロメートルサイズの粒子が,バイモダルの粒子のサイズ分布を誘発した.
張力強さや柔軟性を含む機械的性質が評価されました.

主要な成果:

処理された銅は,バイモダルの粒状構造を示した.
高強度はナノ結晶マトリックスに起因し,ホール-ペッチ関係と一致しました.
不均質な微細構造は,張力硬化を促進し,その結果,引力屈性が大幅に向上しました (故障までの延長が65%,均質な延長が30%).

結論:

熱力学的処理により,高強度と高可塑性の両方を備えた頑丈なナノ構造の金属を作成できます.
バイモダルの微細構造は,ナノ結晶材料の牽引性能を向上させるための鍵です.
この進歩は,微電気機械および生物医学システムにおける成形操作と高性能構造アプリケーションの有望性を示しています.

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