Super304H和HR3C奥氏体钢在模拟锅炉高硫气氛中的腐蚀行为

Corrosion behavior of Super304H and HR3C austenitic steels in simulated flue-gas boiler environments with high sulfur concentration

将Super304H、HR3C钢试样置于700℃下不同SO_2浓度(0.5%,1.5%)模拟气氛中,间隔一定时间取出样品称重,获得腐蚀动力学曲线。采用XRD、SEM和EDS等测试技术对腐蚀产物成分、结构和形貌进行分析。结果表明:在高硫环境中HR3C钢比Super304H钢更耐蚀。Super304H钢的腐蚀产物主要由疏松的富铁氧化物,部分Cr、Ni的氧化物以及尖晶石类化合物和少量的硫化物组成;HR3C钢的腐蚀产物主要为Cr_2O_3和铁的氧化物以及少量硫化物。随着SO_2浓度升高,腐蚀层增厚,腐蚀产物中局部出现S富集,加速了合金腐蚀。

The high temperature corrosion behaviors of Super304 H and HR3C steels in the simulated flue gas with 0.5%,1.5% content of SO_2 at 700 ℃ were studied.The mass change of the steels was obtained at intervals during the test to study the corrosion kinetics of the samples.The morphology and composition of the corrosion products were investigated by using XRD,SEM and EDS analysis.The results show that the corrosion resistance of the HR3C steel in high SO_2 content is much better than that of Super304 H steel.The corrosion product of the Super304 H steel is composed of iron oxides,Cr_2O_3,NiO and minor compound oxides with spinel structure such as（ Ni,Cr）Fe_2O_4、Cu Fe_2O_4 and sulfide.The corrosion products of the HR3C steel mainly contain Cr_2O_3,iron oxides and sulfides.With the increasing of SO_2 concentration in the atmosphere,the thickness of the oxide films increases,and sulfur segregation occurs in the corrosion affected zone,which accelerates the corrosion of the alloy.