水晶の可塑性における準周期的な出来事と,自己組織化した雪崩振動器の発生
Stefanos Papanikolaou1, Dennis M Dimiduk, Woosong Choi
1Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06520-8286, USA. stefanos.papanikolaou@yale.edu
Nature
|October 27, 2012
まとめ
ストレスのあるシステムにおける雪崩は,ゆっくりとしたリラックスプロセスによって影響を受けることがあります. この研究は,新しい"自己組織的な雪崩振動器"の臨界状態を明らかにし,素材や地質的な出来事における雪崩のダイナミクスに影響を与えています.
科学分野:
- マテリアルサイエンス 材料科学
- 凝縮物質物理学 凝縮物質物理学
- 地質物理学 地質物理学とは地質物理学です.
背景:
- システムにおける外部のストレスが,急激で衝動的な出来事,つまり"雪崩"によって緩和されることが多い.
- しかし,これらのイベントの間にゆっくりとしたリラックスプロセスが発生し,雪崩の行動に影響を与える可能性があります.
- 例として,地震の間の水流や,結晶の変位流などがあります.
研究 の 目的:
- ストレスのあるシステムにおける雪崩のダイナミクスに対するゆっくりとしたリラクゼーションの影響を実験的に調査する.
- 新しい臨界状態の出現とその性質を探求する.
- ゆっくりとリラックスする理論的モデルを開発し,検証する.
主な方法:
- ニッケルミクロクリスタルの実験的な圧縮は,張力率の3つの大きさで,
- 変位の雪崩の分析および計算モデリング,変位の緩和を含むように拡張された.
- 準周期的な雪崩爆発と臨界指数の観察と分析.
主要な成果:
- ニッケル・マイクロクリスタルにおける非従来の準周期的な雪崩の爆発を観測した.
- ストレントレートが低下するにつれて,より高い臨界指数に注目し,変化した臨界行動を示した.
- 洗練された変位の雪崩モデルで検証された実験結果.
結論:
- 新しい臨界状態を発見した:自己組織化した雪崩振動器.
- この状態は,決定的な臨界点への振動的なアプローチを示します.
- この発見は,雪崩がゆっくりとしたリラックスと競合するときに準周期的なスケール不変性が発生することを示唆しており,これはマイクロプラスチックや地震などの多様なシステムに適用できる.
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