Affiliation:
1. College of Materials Science and Engineering Taiyuan University of Science and Technology 66 Waliu Road Taiyuan 030024 P. R. China
2. State Key Laboratory of Advanced Stainless Steel Taiyuan Iron and Steel (Group) Co. Ltd. 2 Jiancaoping Street Taiyuan 030003 P. R. China
3. College of Materials Science and Engineering Taiyuan University of Technology 79 Yingze W Street Taiyuan 030024 P. R. China
Abstract
The synergistic effects of rare earth (RE) and Mg elements on the high‐temperature oxidation resistance of Fe–20Cr–6Al alloy are investigated in‐depth. The scale on RE–Mg codoped alloy mainly consists of α‐Al2O3/MgAl2O4, with many pores caused by spinel transition. Owing to the segregation of RE ion at the grain boundaries, there is a significant refinement effect of oxide grains, which improves the spallation resistance of scale and offers more grain boundary diffusion pathways for ion transport, resulting in an obvious increase of oxidation weight gain. The findings indicate that RE is beneficial for inhibiting the grow‐up of oxide grains, whereas Mg can weaken the compactness of scale.