对热管接接头的裂纹形成的评估
Min Ji Song1, Keun Hyung Lee1, Jun-Seob Lee2
1Department of Materials Science and Engineering, Chungnam National University, Daejeon 34134, Republic of Korea.
Materials (Basel, Switzerland)
|May 14, 2025
概括
由于电腐蚀和热应力,在受热影响区 (HAZ) 引发了区域供暖管道的裂. 粗粒的HAZ区域呈现出优势腐蚀,导致裂传播,突出显示了接管道中微结构控制的需要.
科学领域:
- 材料科学 材料科学 材料科学
- 腐蚀工程 腐蚀工程
- 机械工程 机械工程
背景情况:
- 区域供暖管道是关键的基础设施.
- 由于复杂的环境和操作因素,可能会发生故障.
- 接接头是材料降解的常见场所.
研究的目的:
- 调查750A双绝缘管道的故障机制.
- 确定热受影响区 (HAZ) 中裂纹形成的根本原因.
- 分析管道故障中腐蚀和机械应力之间的相互作用.
主要方法:
- 视觉检查和机械测试.
- 微结构特性和电化学腐蚀测试.
- 用于应力模拟的有限元分析 (FEA).
主要成果:
- 由于电腐蚀和热膨胀应力,HAZ中发生了裂.
- 在3M NaCl溶液中HAZ表现出阳极性行为,表明对腐蚀的敏感性.
- 粗粒的HAZ显示了最低的腐蚀潜力,促进了坑和裂的开始.
- 在HAZ中,FEA发现了作为应力度器 (>475 MPa) 的微孔.
结论:
- 电腐蚀和热应力是HAZ管道故障的主要驱动因素.
- 微观结构特征,特别是在粗粒的HAZ中,显著影响腐蚀易感性.
- 控制微观结构稳定性和机械完整性对于接管道在腐蚀性,热应力环境中至关重要.
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