単一の波が急速に動いている裂け目のフロントに沿って広がる
E Sharon1, G Cohen, J Fineberg
1The Racah Institute of Physics, The Hebrew University of Jerusalem, Givat Ram, Israel.
Nature
|March 10, 2001
まとめ
新しく発見された新発見物です.
科学分野:
- 骨折力学 骨折力学とは
- マテリアルサイエンス 材料科学
- 固体力学 固体力学とは
背景:
- 脆い素材の亀裂は,2D素材の1Dオブジェクトとして単純化されることが多い.
- 現実の3D素材は,単一のフロントを持つ平面的な亀裂表面を示しています.
- 不均一性と相互作用するクラックフロントのダイナミクスと形態は理解されていません.
研究 の 目的:
- 3Dの脆い材料におけるクラックフロントのダイナミクスを研究する.
- クラックフロントの行動における物質の不均一性の役割を理解する.
- 骨折表面形態学の形成を説明する.
主な方法:
- 3Dの脆い材料でのクラックフロントの動態のシミュレーション.
- クラックフロントに沿った波の伝播の分析.
- クラックフロントの相互作用とアスペリティの試験.
主要な成果:
- 混乱は,クラックフロントに沿って広がる長寿の局所的な波 ("フロント波") を生み出します.
- フロント波はレイリー波の速度で伝播する.
- 反対に広がるフロント波は形状と振幅を維持し,表面の痕跡を生成します.
結論:
- フロント波は本質的に3D現象であり,2D断裂理論には存在しない.
- フロント波は,慣性と消散で割れ目を生み出します.
- これらは,アスペリティとの相互作用中のクラックコヒーレンスを説明する可能性がある.
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