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Fe-15Cr 和 Fe-30Cr 合金在1000至1200℃空气中氧化时,表面富铁氧化伤的发展导致保护性Cr_2O_3层衰退,氧化速率增大。添加 Ce 可延迟衰退过程的发生,从而大幅度减低氧化速率。随氧化温度和合金成份变化,Cr_2O_3层衰退的开始时间和发展特征随之改变,Ce 对氧化行为的影响因而呈现出规律性的变化。研究发现,合金中 Cr 的内氧化使 Cr_2O_3层形成小舌包卷合金并使其氧化成富铁氧化物。这是Cr_2O_3层衰退的原因之一。含 Ce 合金中 Ce 的优先内氧化则降低自氧化层进入合金的氧浓度,抑制Cr 的内氧化。氧浓度降低还能促进 Si 的内氧化物在氧化层/合金界面集聚。
When the Fe-15Cr and Fe-30Cr alloys oxidize in the air from 1000 to 1200 ℃, the development of iron-rich oxide on the surface leads to the deterioration of protective Cr 2 O 3 layer and the oxidation rate increases. Adding Ce delays the onset of the decay process, greatly reducing the oxidation rate. With the change of the oxidation temperature and alloy composition, the onset and development characteristics of the Cr 2 O 3 layer decline and the effect of Ce on the oxidation behavior changes regularly. It is found that the internal oxidation of Cr in the alloy causes the Cr_2O_3 layer to form a small tongue-wrapped alloy and oxidizes it to an iron-rich oxide. This is one of the reasons for the decline of Cr 2 O 3 layer. The preferential internal oxidation of Ce in the Ce-containing alloy reduces the oxygen concentration entering the alloy from the oxide layer and suppresses the internal oxidation of Cr. The reduced oxygen concentration also promotes the internal Si oxide agglomeration at the oxide / alloy interface.