本實驗是研究鐵鋁基合金在650.degree.C熔融碳酸鹽中的耐蝕性。實驗結果說明,Fe-40Al合金的腐蝕動力學為擴散機構所控制。鐵鋁基合金的重量損失隨著鋁含量的增加而降低,這是因為Fe-Al基合金的結構於25% Al含量時形成DO/sub 3/結構,而在36% Al含量時形成B/sub 2/規則相結構,隨著規則度的增加,鐵的擴散速率降低的緣故。Fe-Al基合金的表面腐蝕型態為沿晶腐蝕,添加Cr合金元素可提升其耐蝕性。 The corrosion resistance of Fe-Al alloys in a molten carbonate bath were investigated at 650.degree.C for different exposure time. The corrosion kinetics followed the parabolic rate law and controlled by diffusion mechanism in Fe-40Al alloy. Weight loss decreased with increasing the content of Al in Fe-Al alloys. Owing to the order structure of Fe-Al alloys the content of aluminum in Fe-Al alloys will decrease the outward diffusion of iron. The forms of corrosion of Fe-Al alloys were intergranular corrosion. The improvement of corrosion resistance of Fe-Al alloys can be obtained by the addition of chromium.