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研究表面分別有混合盐Na_2SO_4-NaCl,Na_2SO_4-V_2O_5和纯Na_2SO_4沉积并在模拟燃气气氛中Fe_3Al和FeAl于600℃的热腐蚀,在所有试验条件下两种合金均发生热腐蚀。随试验时间的延长、纯Na_2SO_4和Na_2SO_4-NaCI引起的腐蚀明显减缓,而Na_2SO_4-V_2O_5的腐蚀则加剧并长时持续。FeAl一般较之Fe_3AI耐蚀,只有在Na_2SO_4-NaCl情况下两者腐蚀性能相近。所有合金的腐蚀产物层总是由一高铁的外层和含铝与铁和少量硫的内层组成,后者的成分随所涂盐的组成而变化。在一定程度上腐蚀机制涉及氧化-硫化与氧化物的熔融等。
Hot corrosion of Fe 3 Al and FeAl in 600 ℃ were observed in the simulated gas atmosphere with mixed salt Na_2SO_4-NaCl, Na_2SO_4-V_2O_5 and pure Na_2SO_4, respectively. Hot corrosion was observed in all the alloys under all experimental conditions. With the prolongation of test time, the corrosion caused by pure Na_2SO_4 and Na_2SO_4-NaCI slowed down obviously while the corrosion of Na_2SO_4-V_2O_5 increased and continued for a long time. Compared with Fe_3AI, FeAl is generally corrosion-resistant, and its corrosion performance is similar only in the case of Na_2SO_4-NaCl. The corrosion product layer of all the alloys is always composed of an outer layer of high-speed iron and an inner layer of aluminum and iron and a small amount of sulfur whose composition varies with the composition of the salt applied. To a certain extent, the corrosion mechanism involves the oxidation-sulfidation and the melting of oxides.