Effect of isothermal oxidation on luminescent property and microstructure of YSZ∶Eu thermal barrier coating

doi:10.13251/j.issn.0254-6051.2020.05.003

Abstract

Abstract: Three different types of coatings were deposited by pure YSZ powders and 2mol% Eu³⁺ doped powders. The luminescent properties of the coatings were tested by using a laser spectrometer after isothermal oxidation treatment at 1100 ℃ for 100, 300, 800 h respectively, the morphologies of the three different types of coatings were analyzed by scanning electron microscope (SEM), and the element analysis of the coatings was studied by energy dispersive spectrometer (EDS). The results show that the fluorescence intensities of the YSZ∶Eu coatings decrease with the increase of the isothermal oxidation treatment time, and the as-received specimen without heat treatment has the highest fluorescence intensity. The YSZ∶Eu emission spectrum mainly consists of two emission peaks at 502 nm and 606 nm, and the emission peak at 606 nm is stronger than that at 592 nm. Under the same heat treatment conditions, the fluorescence intensity of the YSZ∶Eu coating is proportional to the content of Eu³⁺. The porosity ratio of the three coatings is 8.41%, 8.48% and 8.37%, respectively. The Vickers hardness of the coatings is between 430 and 440 HV0.3, indicating that the doping of 2mol% of Eu³⁺ ions cannot cause any influence on the density and the hardness of the YSZ coatings. And the Eu³⁺ ions do not diffuse inside the coating even after isothermal oxidation treatment at 1100 ℃ for 800 h.

Key words: thermal barrier coating, Eu³⁺ doping, isothermal oxidation treatment, fluorescence intensity, micromorphology

CLC Number:

TG148

Liu Yankuan, Yang Liping, Wang Zhiping. Effect of isothermal oxidation on luminescent property and microstructure of YSZ∶Eu thermal barrier coating[J]. Heat Treatment of Metals, 2020, 45(5): 12-16.

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