目的 研究S30432和HR3C涂覆某电厂煤灰和合成煤灰后在700 ℃模拟锅炉气氛中的腐蚀行为，分析两种材料的腐蚀机理。方法 将表面涂覆煤灰的S30432、HR3C试样置于700 ℃含0.3%SO2模拟锅炉烟气环境中腐蚀2000 h，间隔一定时间取出样品称量，获得腐蚀动力学曲线。腐蚀2000 h后，清洗去除样品表面的腐蚀产物，获得样品腐蚀后的损失量，计算两种材料在合成煤灰和某电厂煤灰中的腐蚀加速比。采用XRD、SEM和EDS对腐蚀产物成分、微观形貌和结构进行分析。结果 在某电厂煤灰环境中，S30432和HR3C的腐蚀产物均为Fe2O3、Cr2O3和FeCr2O4；在合成煤灰中，S30432残留腐蚀产物主要为FeCr2O4和FeS，而HR3C则主要为Fe2O3、Cr2O3。在某电厂煤灰中，S30432和HR3C表面生成了较厚的腐蚀产物层，且腐蚀产物层中有大量孔洞；在合成煤灰中，S30432、HR3C腐蚀产物几乎剥落殆尽。结论 由于HR3C中的Cr和Ni含量较高，其耐腐蚀性能明显优于S30432。由于合成煤灰中硫酸盐含量较高，因此合成煤灰中S30432和HR3C的腐蚀明显加快，S30432和HR3C在合成煤灰和某电厂煤灰中腐蚀的加速比分别为3.03和3.28。

The work aims to study the corrosion behavior of S30432 and HR3C coated with power plant coal ash and synthetic coal ash in the simulated boiler atmosphere at 700 ℃, to obtain the corrosion acceleration ratio of synthetic coal ash to the power plant coal ash and analyze the corrosion mechanism of two kinds of materials. The S30432 and HR3C steel samples coated with coal ash were placed in simulated boiler environments with 0.3% SO2 for 2000 h and then taken for weighing after certain interval, to obtain the corrosion kinetics curves. After 2000 h of corrosion, the corrosion products on the surface of the sample were cleaned to obtain the weight loss of the sample, and samples surface were cleaned and the weight loss of the samples after corrosion was obtained. The obtained by weighting samples at intervals. After 2000 hours of corrosion, the corrosion the corrosion acceleration ratio of the materials in synthetic coal ash and the power plant coal ash was calculated. The composition, morphology and structure of the corrosion products were analyzed by XRD, SEM and EDS. The corrosion products were identified as Fe2O3, Cr2O3 and FeCr2O4 when S30432 and HR3C were coated with the power plant coal ash. The main residual corrosion products were FeCr2O4 and FeS when S30432 was coated with synthetic coal ash. However, the corrosion products formed on the HR3C were Fe2O3 and Cr2O3 under the same condition. A thicker corrosion layer with many pores and cracks formed on the sample surface were observed when S30432 and HR3C were corroded in the the power plant coal ash. The corrosion layer formed on the S30432 and HR3C were almost spalled completely when the sample was coated with sythetic ash. HR3C shows much better corrosion resistance than that of S30432 because of the higher content of Cr and Ni. Due to the high content of sulfate in synthetic coal ash, synthetic coal ash obviously accelerates the corrosion rate of S30432 and HR3C. When S30432 and HR3C are corroded in the synthetic coal ash and the power plant coal ash, the acceleration ratio is 3.03 and 3.28, respectively.