在长期服务中研究T92/Super304H不同钢接接头的IV型破裂行为
Denghui Wang1, Fei Gao1, Zihao Shen1
1School of Materials Science and Engineering, Beihang University, Beijing 100191, China.
Materials (Basel, Switzerland)
|December 17, 2024
概括
在T92/Super304H不同钢接接头的长期使用导致微观结构变化,促进腔核和IV型裂纹. 这种裂纹发生在降低应力下的细粒热受影响区域中,由于沉的粗化和空洞形成.
科学领域:
- 材料科学 材料科学 材料科学
- 金工业是金工业的一个方面.
- 机械工程 机械工程
背景情况:
- T92/Super304H不同钢接接头是高温应用中的关键部件.
- 了解它们的长期性能和故障机制对于运营安全和效率至关重要.
研究的目的:
- 分析经过长期使用 (70,00085,000小时) 的T92/Super304H接接头的微观结构和剩余机械性能.
- 研究导致爬行寿命缩短和这些关节的IV型裂的机制.
主要方法:
- 在服务后对接接头进行微观结构分析.
- 评估剩余的机械性能.
- 金属学检查,以确定沉物演变和空洞形成.
主要成果:
- 延长服务会导致马氏石多角化,并在T92钢侧沉粗.
- 在爬行过程中,空洞核形成发生在沉界面和谷物边界上.
- 随着服务时间的推移,爬行寿命显著减少,导致IV型破裂.
结论:
- 在T92/Super304H接接头中,IV型裂变是由细粒热受影响区域 (FGHAZ) 的沉积物粗和腔核形成的.
- 这种故障模式需要显著的沉粗化,腔核化,以及负载应力大大低于产力强度.
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