ボロン改性超高圧ステンレス鋼の水素脆化
Arthur de Bribean Guerra1,2,3, Daniel Brito Bertoldi1,2, Guilherme Zepon1,2
1Department of Materials Science and Engineering, Federal University of São Carlos, Rod. Washington Luís, São Carlos, SP CEP 13565-905, Brazil.
ACS omega
|September 2, 2025
まとめ
超高圧ステンレス鋼 (SMSS) にボールを加えると強度が向上するが,水素の脆さ (HE) は悪化する. ボロンに富んだSMSSは水素曝露後に有意な機械的分解と脆い骨折を示し,微細構造の最適化の必要性を強調した.
科学分野:
- 材料科学
- 腐食工学
- 水素の脆性に関する研究
背景:
- ボリド網を備えた超圧縮性ステンレス鋼 (SMSS) は,石油とガスに対する優れた耐腐蝕性および耐磨性を提供します.
- 海上環境における水素の脆化 (HE) は,SMSSにとって重大な課題です.
研究 の 目的:
- SMSSの水素脆化感受性に対する異なるボロン濃度 (0.3-0.7 wt%) の影響を調査する.
- 水素充電条件下でのボロン強化SMSSの故障メカニズムを理解する.
主な方法:
- 異なるボロン含有量のSMSSサンプルを3.5%のNaCl溶液で水素で充填する.
- 水素曝露後の遅いストレージ率の牽引試験を用いた機械試験.
- 微細構造分析で 骨折の起源と拡散経路を特定する
主要な成果:
- ボロンの添加は,SMSSの引力強度を高め,可塑性を著しく低下させた.
- SMSS-0.7%Bの強度と伸長が55%以上低下した.
- M2Bボリドによって粒子の境界で発生した,薄い粒子の間断が発生した.
- HEはマルテンシットマトリックスとボリドの両方に影響し,ボリドが豊富な領域で骨折が発生しました.
結論:
- マトリックスとボリドの両方を含むシネージ的脆化メカニズムは,ボロン強化SMSSのHEに寄与する.
- これらの高度な材料の水素抵抗性を向上させるには 微細構造の最適化が不可欠です
- ボロンの添加物は,磨損と腐食に有益ですが,要求の高いアプリケーションでは,水素の脆さについて注意深く検討する必要があります.
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