Affiliation:
1. Changsha University of Science and Technology
2. Army Academy of Armored Forces
Abstract
Abstract
With the increase of the turbine inlet temperature of high-efficiency gas turbines, developing the bond-coat with higher temperature oxidation resistance is also necessary. In the paper, CoCrNiAl0.6 middle entropy alloys with different content reactive elements Y were prepared, and the effects of Y content on the microstructure and oxidation behavior at 1200 ℃ were studied. All alloys consist of β phase and γ phase，but CoCrNiAl0.6Y (0.11) shows some sub-micron γ phase precipitates are within the β phase. The oxidation behavior at 1200 ℃ of CoCrNiAl0.6Yx (x=0.05, 0.08, 0.11) confirms that dense oxide scale can be formed at the alloy surface, the surface with aluminum oxide accompanied yttrium oxide makes better adhesion between the matrix and oxide scale. The CoCrNiAl0.6Y (0.11) alloy has the best oxidation resistance with lower oxidation rate of 5.704×10-12 g2/(cm4·s), which is also far better than the conventional NiCoCrAlY alloy with typical compositions.
Publisher
Research Square Platform LLC
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