結晶固体における予期せぬストレスト硬化
Chao Jiang1, Srivilliputhur G Srinivasan
1Structure/Property Relations Group, MST-8, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA. chaopsu@gmail.com
Nature
|April 12, 2013
まとめ
生物学的組織で見られる特質であるストレストイフニングは,驚くべきことにセメント (Fe3C) やアルミニウムボロカルバイド (Al3BC3) のような無機固体でも発生する. この現象は,これらの材料に例外的な強度を与え,伝統的な材料設計原則に挑戦します.
科学分野:
- 材料科学 材料科学とは
- 固体物理 固体物理学
- コンピューティング・ケミストリー
背景:
- ストレストイフニングは,生物学的材料が過剰な変形を防ぐために不可欠です.
- 張力強化の理解は,金属やセラミックの設計を進める可能性があります.
- 非有機結晶固体は,通常,平衡に近い変形に対する抵抗性が低い.
研究 の 目的:
- 無機結晶固体におけるストレスト硬化を調査する.
- 先進的な材料の設計のためのストレスの硬化の可能性を探求する.
- セメント (Fe3C) とアルミニウムボロカルバイド (Al3BC3) の張力加固の背後にあるメカニズムを解明する.
主な方法:
- 量子力学的な計算が採用されました.
- 理想的な切断強度と切断モジュール比率の分析.
- Fe3CとAl3BCの硬化のための原子レベルのメカニズムの調査3.
主要な成果:
- Fe3CとAl3BC3.3でストレストイフニングが観察されました.
- これらの材料は,絶妙に高い理想的な切断強度と切断モジュール比 (1.14 for Fe3C, 1.34 for Al3BC3) を表しています.
- Fe3Cは,Fe6Cスラブの可逆的なクロスリンクによって硬化し,3D共振ネットワークを形成する;Al3BC3は,Al-B排斥によって共振ネットワークの不安定化により硬化する.
結論:
- ストレスの硬化は,単純な無機結晶固体において以前は認識されなかった現象である.
- この発見は,高シールモジュールが材料の硬さと強さを確実に予測するという仮定に異議を唱える.
- 材料の選択と高強度の結晶材料の設計に関する新しい洞察が提供されています.
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