| 引用本文: | 陆永浩,陈子瑞,朱晓锋.敏化处理对Z3CN20-09M不锈钢高温水应力腐蚀的影响[J].材料科学与工艺,2014,22(5):73-79.DOI:10.11951/j.issn.1005-0299.20140513. |
| LU Yonghao,CHEN Zirui,ZHU Xiaofeng.Effect of sensitization treatment on high temperature water SCC of Z3CN20-09M stainless steel[J].Materials Science and Technology,2014,22(5):73-79.DOI:10.11951/j.issn.1005-0299.20140513. |
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| 摘要: |
| 为了研究敏化处理对Z3CN20-09M不锈钢高温水应力腐蚀行为的影响,使用敏化处理的Z3CN20-09M不锈钢制成U弯试样,并置于250、290及320 ℃的高温水中进行应力腐蚀开裂实验,采用扫描电镜观察了高温水实验后试样的氧化膜厚度以及应力腐蚀裂纹的萌生及扩展行为.结果表明:敏化处理增加了氧化膜的厚度,降低了耐蚀能力,使SCC敏感性增大；温度较高时,敏化处理的影响较大；铁素体相容易被侵蚀,大多数点蚀坑产生于铁素体中；SCC裂纹优先在点蚀坑底部和奥氏体/铁素体相界位置处形成；相界面对SCC裂纹的影响取决于SCC裂纹相对于相界面的取向,SCC裂纹扩展方向平行于相界面时裂纹易沿着相界扩展,SCC裂纹扩展垂直于相界面方向时相界面对裂纹扩展起阻碍作用. |
| 关键词: Z3CN20-09M 敏化处理 SCC裂纹 萌生和扩展 相界面 |
| DOI：10.11951/j.issn.1005-0299.20140513 |
| 分类号:TG172 |
| 基金项目:国家科技重大专项课题(2011ZX06004-009)；中央高校基本科研业务费(FRF-TP-09-030B). |
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| Effect of sensitization treatment on high temperature water SCC of Z3CN20-09M stainless steel |
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LU Yonghao, CHEN Zirui, ZHU Xiaofeng
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(National Center for Materials Service Safety, University of Science and Technology Beijing, Beijing 100083, China)
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| Abstract: |
| To study effect of sensitization treatment on high temperature water SCC(stress corrosion cracking)behavior of Z3CN20-09M stainless steel, sensitized U-bend specimens were put into high temperature water. The thickness of oxidation film and the initiation and propagation of SCC cracks were observed using SEM. The results indicated that the sensitization increased thickness of oxide films and decreased corrosion resistance ability, resulting in increase of SCC sensitivity of the materials. The higher the sensitization temperature, the greater the effect of sensitization treatment. Ferrite was favorable to be etched, which resulted in nucleation of most corrosion pits in ferrite phase. SCC cracks initiated preferentially at bottom of corrosion pits and along ferrite/austenite interface. The effect of phase interface on SCC crack strongly depended on the relative orientation of SCC crack to the phase interface. When SCC crack propagated parallel to the phase interface, it was inclined to propagate along the phase interface. When SCC crack propagation direction was perpendicular to the phase interface, phase interface hindered the propagation of SCC crack. |
| Key words: Z3CN20-09M sensitization SCC crack nucleation and propagation phase interface |
