The high temperature corrosion characteristic of Super304H, TP347H, and HR3C steel in an ultra‐supercritical coal‐fired boiler with service time of 17,973 h was investigated. The samples were analyzed by XRD, SEM, and EDS. The results showed that corrosion scales were composed and could be divided into three layers, including outer layer with composite reaction of alkalis and sulfate, middle layer with oxidation, and penetrated inner layer with oxidation and sulfidation. In addition, spalling of corrosion scales in the Super304H and TP347H samples was observed with the reasons of low Cr content and thermal expansion difference between different corrosion layers.

中文翻译：

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Super304H，TP347H和HR3C钢在超超临界燃煤锅炉中的高温腐蚀特性研究▴

研究了Super304H，TP347H和HR3C钢在超超临界燃煤锅炉中使用时间为17,973 h的高温腐蚀特性。通过XRD，SEM和EDS分析样品。结果表明，腐蚀垢是组成的，可分为三层：碱与硫酸盐复合反应的外层，氧化的中间层，氧化和硫化的渗透内层。另外，由于低Cr含量和不同腐蚀层之间的热膨胀差异，在Super304H和TP347H样品中观察到腐蚀垢剥落。