Exploring the high-temperature steam oxidation behaviors of the lean-Cr (7–10 wt%) FeCrAl alloys

The high-temperature steam oxidation behaviors of the four lean-Cr (7–10 wt% Cr) FeCrAl alloys containing minor elements and the Fe13Cr4.5Al alloy without minor elements (as a reference) were systematically investigated at 1100 ℃. The cross-sectional microstructure of the products after oxidation was investigated with FIB + TEM. The results show that the oxidation kinetics of these alloys except for 7Cr alloys obeyed the sub-parabolic rate law. The ability to form a protective alumina scale was worsened by the reduction of Cr content. The content of Cr should be higher than 7 wt% to promote alumina scale formation at 1100 ℃.