ショートレンジオーダーとCrCoNiの中間エントロピー合金への影響
Ruopeng Zhang1,2, Shiteng Zhao1,2, Jun Ding3
1Department of Materials Science and Engineering, University of California, Berkeley, CA, USA.
Nature
|May 21, 2020
まとめ
短距離の秩序は,CrCoNiの中間のエントロピー合金で実験的に観察されました. この原子の配置は 硬さや堆積欠陥エネルギーなどの 機械的性質を高めます
科学分野:
- 材料科学
- 金属工学
- 固体物理学
背景:
- 伝統的な合金にはランダムな原子分布や二次相がある.
- 多重主元素合金 (MPEA) は,強化された機械特性を持つ単相固体溶液である.
- 中等エントロピー合金 (MEAs) と高エントロピー合金 (HEAs) は,MPEAsのタイプです.
研究 の 目的:
- 実験的に,CrCoNiの中間のエントロピー合金における短距離秩序の存在と影響を調査する.
- 短距離秩序と機械的性質の関係を探求する.
主な方法:
- 構造的特徴を観察するために,エネルギーフィルター伝送電子顕微鏡 (EF-TEM) が使用されました.
- 分析はCrCoNiの中性エントロピー合金システムに焦点を当てた.
主要な成果:
- 短距離注文に起因する構造的特徴がCrCoNi MEAで観察されました.
- 短距離のオーダーが増加すると スタッキング・フォルトのエネルギーが増加します
- 高度な秩序は材料の硬さを増やすことにつながった.
結論:
- 短距離オーダーは存在し,MEAでは実験的に検証できます.
- 熱機械処理による短距離調整は,合金特性を調整する新しい方法を提供します.
- この発見は,優れた機械性能を持つ高度なMEAとHEAを設計するための新しい経路を開きます.
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