C-276哈氏合金换热管失效分析与预防

摘要

C -276 Hastelloy alloy heat exchange welding tube happened corrosion failure in service,there is a obvious thinning phenomenon in bead area and a hole in local area of the bead. The reason for failed C -276 welded tube was researched through metallography,scanning electric mirror,energy spectrum etc. The results indicate that only cold working on bead, improper welding procedure and subsequent incomplete solution treatment are the root causes of low corrosive resistance in bead. Finally,the relevant preventive measures have been put forward.%C-276哈氏合金焊接换热管在服役中发生了腐蚀失效,焊缝区域明显减薄,焊缝局部有小孔.通过金相、扫描电镜、能谱分析等分析手段对失效的C-276焊接管进行了分析.分析结果表明,仅对焊缝做了冷拉处理、不当的焊接工艺以及随后的不完善固溶处理是导致焊缝区域耐腐蚀性能降低的主要原因.最后提出了相应的预防措施.