グラデント構造鋼のサイクル・クリープに対する優れた抵抗性
Qingsong Pan1, Kunqing Ding2, Song Guo1,3
1Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, P.R. China.
まとめ
研究者達は,高強度なオステニット製のステンレス鋼材を開発しました. この材料は,変位細胞と微細構造の精細化によるユニークなグラデント階層により,著しく低いサイクルクリープ率を示しています.
科学分野:
- 材料科学
- 機械工学
- 金属工学
背景:
- サイクルクリープは構造材料の疲労障害メカニズムです.
- 平均ストレスの非対称なストレスのサイクルは,蓄積的なプラスチックストレスを引き起こし,早期の材料の故障につながります.
- 材料工学の重要な課題である.
研究 の 目的:
- 新しい高強度オステニット製のステンレス鋼で 超高耐性を証明するためです
- 周期的な爬行に対する耐性を高める微細構造的メカニズムを調査する.
- 先進的な材料の設計のためのグラデント変位アーキテクチャの可能性を探求する.
主な方法:
- 高強度オステニット型ステンレス鋼の製造 変位細胞のグラデント階層
- 非対称なストレスサイクルの下でのラッチング速度を測定するための実験試験.
- 変形による変形と細胞構造を観察するための微細構造分析.
主要な成果:
- 開発された鋼は,粗粒の対比よりも2〜4倍の大きさのクラッチング率を示した.
- 六角形の密集したナノ層へのマルテンシート変換による持続的な微細構造の精錬が観察されました.
- グラデント変位アーキテクチャは,周期的な軟化を効果的に緩和し,ストレスの局所化を抑制しました.
結論:
- グラデント変位アーキテクチャは,高強度,ラッチング抵抗性のある材料のための有望な設計戦略を提供します.
- 変形による微細構造の精錬は,ラチェッティングのストレスを抑制する鍵です.
- このアプローチにより 構造部品の耐久性と寿命が向上します
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