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通过电弧离子镀制备了NiCrAlYRe和NiCrAlY涂层,经真空热处理后涂层均由γ′-Ni_3Al、γ-Ni、β-NiAl和α-Cr四相构成。在NiCrAlYRe涂层中,Re主要存在于α-Cr相,Re促进了α-Cr相在涂层中的析出,并提高了α-Cr在长期氧化过程中的稳定性,特别在氧化膜/涂层界面上析出了大量富Re的α-Cr。由于富Re的α-Cr同α-Al_2O_3具有极为接近的热膨胀系数,降低了氧化膜中的热应力,提高了NiCrAlY涂层表面抗剥落能力。添加Re明显提高了NiCrAlY涂层在900℃90%Na_2SO_4+10%K_2SO_4介质中的抗热腐蚀性能。
NiCrAlYRe and NiCrAlY coatings were prepared by arc ion plating. The coatings were all composed of γ’-Ni_3Al, γ-Ni, β-NiAl and α-Cr phases after vacuum heat treatment. In the NiCrAlYRe coating, Re mainly exists in the α-Cr phase, and Re promotes the precipitation of the α-Cr phase in the coating and improves the stability of the α-Cr in the long-term oxidation process, especially in the oxide film / A large amount of α-Cr rich in Re precipitated on the interface of the layer. As the Re-rich α-Cr and α-Al 2 O 3 have extremely close thermal expansion coefficient, the thermal stress in the oxide film is reduced and the anti-spalling ability of the NiCrAlY coating is improved. The addition of Re obviously improved the hot corrosion resistance of NiCrAlY coating in 900 ℃ 90% Na_2SO_4 + 10% K_2SO_4 medium.