ネガティブ・スティフネス・インクルージョンを持つ複合材料における極端なダッピング
1Department of Engineering Physics, University of Wisconsin-Madison, Wisconsin 53706-1687, USA. lakes@engr.wisc.edu
Nature
|March 30, 2001
まとめ
研究者らは実験的に,陰性硬性インクルージョンを持つ複合材料を作成しました. この新しい素材は,例外的な緩と調節可能な硬さを示し,高度な構造アプリケーションの可能性を秘めています.
科学分野:
- マテリアルサイエンス 材料科学
- 機械工学の機械工学
- 固体物理 固体物理学
背景:
- ポジティブな硬さは,力と位移が同じ方向にある材料を記述します.
- 負の硬さは,力と位移が反対方向にあるときに発生し,しばしば蓄積されたエネルギーと不安定性に関連しています.
- 理論的なモデルは,ポジティブな硬度マトリックス内の負の硬度インクルージョンを安定させることが可能であることを示唆しています.
研究 の 目的:
- 安定した負の硬度インクルージョンを持つ複合材料を実験的に実現し,調査する.
- これらの新しい複合材料の機械的緩と硬さの特性を調査するために.
- ネガティブ・スティフネス・インクルージョンの有効性を,ダイヤモンドなどの伝統的な硬化剤と比較するために.
主な方法:
- 複合材料の製造は,純亜鉛のマトリックスの中に,鉄弾性バナジウム二酸化炭素の負の硬度インクルージョンを埋め込むことによって行われます.
- 結果の複合材料の機械的緩と硬さの異常を実験的に特徴づける.
- 複合物の性質を決定するインクルージョンによって誘発される局所性菌株の役割の分析.
主要な成果:
- 安定した負の硬度インクルージョンを組み込んだ複合材料の実験的実現が成功しました.
- 開発された複合材料は,極端な機械的なダッピングと,硬さの大きな異常を示しています.
- ネガティブな硬度インクルージョンは,特定の温度範囲内のダイヤモンドインクルージョンと比較して優越した硬度強化を示しました.
結論:
- 複合材料のアプローチは,負の硬性インクルージョンを効果的に安定させ,ユニークな材料特性を生み出します.
- これらの材料は,構造要素やアクチュエータなど,高いダッピングを必要とするアプリケーションの有望性を示しています.
- この発見は,機械的な反応を合わせた高度な材料を設計するための新しい道を開く.
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