中文摘要：

以700℃级先进超超临界燃煤锅炉水冷壁候选材料T24和T92钢为研究对象,在600℃模拟水冷壁附近还原性烟气工况下,对两种材料进行了1200 h高温烟气腐蚀试验。通过腐蚀动力学曲线、X射线衍射（XRD）、扫描电镜（SEM）、能谱（EDS）研究了其高温腐蚀行为及腐蚀机理。结果表明：两种材料均发生高温腐蚀,腐蚀动力学曲线均满足抛物线规律,而且T24腐蚀速率明显大于T92的。两种材料腐蚀1200 h后腐蚀产物均呈三层结构,外层富Fe、S,中层富Fe、O,内层富Fe、S、O,T92钢内层还富有Cr元素。较高Cr含量使得T92钢生成一定厚度的Cr2O3,Cr2O3能抑制H2S及游离态硫的扩散,增强了其抗腐蚀能力。

英文摘要：

Taking T24 and T92 steel for 700 ℃ advanced ultra-supercritical（A-USC） coal fired boiler water wall candidate materials as research object. The 1200 h high temperature fireside corrosion experiment of the material exposed to the simulated reducing flue gas near water wall at 600 ℃ were investigated. The high temperature corrosion behavior and corrosion mechanism of the material were characterized by corrosion dynamics curve, XRD, SEM and EDS. The results indicate that both the materials show high temperature corrosion. The corrosion parabolic kinetics curve can meet parabolic law. The corrosion rate of T24 is greater than that of T92. The three corrosion layers appear in both the materials after corrosion for 1200 h, such as Fe and S rich in the outer layer, Fe and O rich in the middle layer and Fe, S and O rich in the inner layer.The inner layer of T92 steel is also rich in Cr element. The higher content Cr can make the generation of the Cr2O3 in some thickness on T92. Cr_2O_3 can inhibit the diffusion of H_2S and free sulfur, which can improve the corrosion resistance of T92.