In:
Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films, American Vacuum Society, Vol. 38, No. 2 ( 2020-03-01)
Abstract:
Al2O3-ZrO2-CeO2 composite coatings were prepared by plasma spraying Al2O3-ZrO2 composite powders with and without CeO2 addition. The microstructure and properties of the Al2O3-ZrO2-CeO2 coatings at high temperature and thermal shock resistance were investigated. The results show that an amorphous phase was formed in the plasma sprayed Al2O3-ZrO2 and Al2O3-ZrO2-CeO2 coatings. The Al2O3-ZrO2 coating consisted mainly of t-ZrO2, α-Al2O3, and γ-Al2O3. The Al2O3-ZrO2-CeO2 coating consisted mainly of t-ZrO2, α-Al2O3, γ-Al2O3, and CeO2. The Al2O3-ZrO2-CeO2 coating was more uniform and denser than the Al2O3-ZrO2 coating. The results after heat treatment showed that the two coatings were stable at 800 °C. With the increase of temperature, the coatings underwent phase transformation at high temperature (1000 and 1200 °C). At 1000 °C, the amorphous phase was obviously reduced, and the amorphous phase was crystallized to form nanocrystals. When the heat treatment temperature was raised to 1200 °C, the intensity of the diffraction peaks of t-ZrO2 and α-Al2O3 increased, the amorphous phase was completely crystallized, and γ-Al2O3 was transformed into α-Al2O3. The porosity of the two coatings decreased and the hardness increased after heat treatment. The thermal shock resistance of the coatings on the TC4 titanium alloy substrate was better than that on the Q235 steel substrate. The thermal shock resistance of the Al2O3-ZrO2-CeO2 coating was better than that of the Al2O3-ZrO2 coating.
Type of Medium:
Online Resource
ISSN:
0734-2101
,
1520-8559
Language:
English
Publisher:
American Vacuum Society
Publication Date:
2020
detail.hit.zdb_id:
1475424-1
detail.hit.zdb_id:
797704-9
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