超細粒度構造鋼の性の逆温度依存度
Yuuji Kimura1, Tadanobu Inoue, Fuxing Yin
1National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan. kimura.yuuji@nims.go.jp
まとめ
この研究は,超高強度鋼鉄の性の逆温度依存性を明らかにしています. 低温での強度の向上は,材料の頑丈性を向上させ,典型的な脆性の行動に逆らいます.
科学分野:
- マテリアルサイエンス 材料科学
- メタルルジーは,金属の製造業です.
- 機械工学の機械工学
背景:
- 材料は通常,より高い温度で柔らかい振る舞いを表し,より低い温度で脆くなります.
- ボディセンター立方体 (bcc) 鋼は,通常,温度が下がるにつれて,柔らかいから脆いへの移行を示します.
研究 の 目的:
- 超細長いフェライト粒子の構造を持つ超高強度BCC鋼の温度に依存する性を調査する.
- 性の温度依存の逆のメカニズムを理解するために.
主な方法:
- 超高強度bcc鋼の加工には熱機械処理が用いられました.
- 微細構造分析は,超細長いフェライト粒やナノメートルサイズのカルビッドに焦点を当てました.
- 性および強度が60°Cから-60°Cまでの温度範囲で測定されました.
主要な成果:
- 性の逆の温度依存が観察され,典型的な柔らかいから脆い行動と対照的に見られました.
- 低温 (−60°Cまで) の耐久性の向上は,収量強度の増加と関連していた.
- フェライト粒の束の中に並べられた割れ目の平面に亀裂の分岐が生じるデラミネーションは,硬化メカニズムとして特定されました.
結論:
- 研究された超高強度BCC鋼は,収縮強度が増加したため,低温で強度が向上しています.
- 独特の超細長いフェライト粒子の構造とナノカービッド強化は,この逆の温度依存性に寄与しています.
- この発見は,低温アプリケーションのための高性能鋼の設計に関する新しい視点を提示しています.
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