不均質な軟体固体の遅延骨折
1D. Bonn, M. Prochnow, K. Ben-Djemiaa, J. Meunier, Laboratoire de Physique Statistique de l'Ecole Normale Superieure, 24 rue Lhomond, 75231 Paris Cedex 05, France. H. Kellay, Centre de Physique Moleculaire Optique et Hertzienne, Universit
Science (New York, N.Y.)
|April 29, 1998
まとめ
ポリマーゲルの骨折は,固体の瞬間の破裂とは異なり,遅延することができます. 恒定力の下で観測されたこの遅延骨折は,活性化エネルギーの計算とゲルの計算によって説明されます.
科学分野:
- 材料科学 材料科学とは
- ポリマー物理学 ポリマー物理学
- 骨折力学 骨折力学とは
背景:
- ポリマーゲルは,結晶型固体とは異なるユニークな機械的性質を備えています.
- 伝統的な材料の骨折は,通常,重大なストレスに達すると即座に発生します.
- ポリマーゲルの遅延骨折現象は,まだ完全に理解されていません.
研究 の 目的:
- ポリマーゲルにおける自発的な骨折の背後にあるメカニズムを調査する.
- ゲルにおけるクラックの拡散の時間依存性の性質を特徴づけるために.
- ポリマーネットワークの遅延骨折を説明する理論的枠組みを開発する.
主な方法:
- 恒常的な施力下での自発的な骨折の実験的観察.
- クラック核形成と拡散遅延の測定.
- クラック核形成の活性化エネルギーの理論的計算.
- フラクタル次元を用いたゲルネットワークの不均一性の分析.
主要な成果:
- ポリマーゲル骨折は,力の適用後,最大15分までの大きな遅延を示します.
- 骨折の遅延は,適用された力の大きさに依存しています.
- 計算されたアクティベーションエネルギーとフラクタル次元は,観察された遅れた骨折行動と相関しています.
結論:
- ポリマーゲルの破裂は時間に依存するプロセスであり,瞬きではありません.
- 遅れた骨折は,クラック核形成に必要な活性化エネルギーに起因する.
- フラクタル次元によって特徴づけられるゲルネットワークの不均一性は,断裂動態において決定的な役割を果たします.
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