N08800铁镍基合金焊管在实际弯管成型中，时而存在开裂问题。采用宏观观察、化学成分分析、力学性能试验、金相检验、微观分析等方法对焊管在弯管成型过程中的开裂产生原因进行了分析。结果表明：N08800铁镍基合金焊管的开裂均发生在焊缝处。焊接过程中产生的焊缝浮渣、焊缝缩孔是造成焊缝处成型开裂的主要原因。较大尺寸的焊接浮渣会在外力作用下形成凹坑，进一步发展造成开裂。

The cracking problem of N08800 Fe-Ni alloy welded pipe were found in the actual bend froming process sometimes. The cracking causes in the bend forming process of welded pipe were analyzed by means of macroscopic observation, chemical composition analysis, mechanical property test, metallographic examination and microscopic analysis. The results show that the cracking of N08800 Fe-Ni base alloy welded pipe were all located in the weld. The weld slags and welding shrinkage cavities during welding were the main reasons for the weld cracking during forming. The larger welding slags formed pits under the action of external force and further development caused cracking.