曲がった転位系の連続体力学近似
A Jason Marx1,2, Stefan Sandfeld2, Thomas Hochrainer3
1Fachbereich Produktionstechnik, Fachgebiet 15, Universität Bremen, Bibliothekstraße 1, Bremen, 28359 Germany.
まとめ
本研究は結晶塑性における転位の自己相関を解析し、シミュレーションにおいてそれらが支配的であることを明らかにする。これらの相関の理解は、正確な連続体力学理論の開発に不可欠である。
科学分野:
- 材料科学
- 物性物理学
- 固体力学
背景:
- 結晶塑性は転位の運動と相互作用によって支配される。
- 連続体力学理論は、転位の統計力学から現れることがある。
- 長距離弾性相互作用は、転位相関を考慮する必要がある。
研究 の 目的:
- 転位の自己相関の解析的表現を導出する。
- 転位配置におけるペア相関を解析する。
- 転位半径分布とその曲率との関係を調査する。
主な方法:
- 円形転位ループ配置における自己相関の解析的表現の導出。
- 双極子様転位配置におけるペア相関の解析。
- 離散転位動力学シミュレーションと最大情報エントロピーモデルとの比較。
主要な成果:
- 様々な転位配置における自己相関の解析的表現を導出した。
- 自己相関は数値相関データにおいて支配的であることがわかった。
- シミュレーションからの転位半径分布は、曲率を組み込んだエントロピーモデルと一致する。
結論:
- 自己相関は結晶塑性の理解にとって重要であり、慎重な理論的扱いが必要である。
- 連続体力学的な転位動力学において、物理的に意味のある半径分布を得るためには、曲率に関連する変数が必要である。
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