某热采井825镍基合金液控管道在运行3个月后发生腐蚀失效。通过管材化学成分、力学性能和显微组织分析，腐蚀产物形貌与成分分析对失效管道的腐蚀原因及机理进行了研究。结果表明：825镍基合金液控管道外壁发生严重点蚀，腐蚀失效的原因是氧腐蚀和硫腐蚀，硫来源于井下H₂S与注蒸汽中的O₂反应生成。

An 825 nickel-based alloy hydraulic control pipe of a thermal recovery well experienced corrosion failure after 3 months of operation. The corrosion reasons and mechanism of the failed pipe were studied by analyzing the chemical composition, mechanical properties and microstructure of the pipe and the morphology and composition of the corrosion products. The results show that the outer wall of the 825 nickel-based alloy hydraulic control pipe suffered severe pitting, the corrosion failure was caused by oxygen corrosion and sulfur corrosion, and sulfur was generated by the reaction of downhole H₂S with O₂ in steam injection.