安定した粒子の境界網を持つナノ粒子の合金におけるクリープを抑制する

B B Zhang¹, Y G Tang^1,2, Q S Mei³

¹Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China.

Science (New York, N.Y.)

|November 10, 2022

まとめ

研究者らは,ナノ粒度合金で安定した粒度境界 (GB) ネットワークを作成することで,高温のクリープを防ぐ新しい方法を開発しました. このアプローチは,従来のスーパー合金より性能を大幅に高めています.

科学分野:

材料科学
機械工学
金属工学

背景:

高温のクリープは部品の故障を引き起こします.
穀物境界 (GBs) は通常,クリープを加速します.
GBsを排除することは,クリープ抵抗性を高めるための一般的な戦略です.

研究の目的:

安定した GB ネットワークを使用してクリープを抑制する新しい戦略を調査する.
ナノグレーンの合金による超高性能の可能性を探るため

主な方法:

ナノ粒子の単相ニッケル・コバルト・クロム合金製造
プラスティック変形を誘導し,双子の境界線で相互接続された安定した GB ネットワークを作成します.
700°Cでギガパスカルのストレスの下でクリープの速度をテストする.

主要な成果:

安定した GB ネットワークは,拡散的なクリーププロセスを効果的に抑制しました.
"秒あたり 10^7 の速度で史無前例の爬行抵抗性を達成した.
ナノ構造の合金はクラップ抵抗性において従来のスーパー合金よりも優れています

結論:

安定した GB ネットワークは,高温のクリープ抵抗のために GB 排除の実行可能な代替案を提供します.
設計された GB ネットワークを持つナノ構造の合金には優れた性能があります.
この戦略は,高温アプリケーションのための先進的な材料の開発に希望を持っています.

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