The objective of this study is to evaluate the electrodeposited zirconia (ZrO₂)-modified NiCoCrAlY composite coatings subjected to isothermal oxidation at 1000^∘C under atmospheric conditions for 24 h. NiCoCrAlY composite coatings with 0, 10, 40, and 60wt.% of cobalt contents have been compared. The oxidation studies have revealed that the doping of yttrium (Y) and ZrO₂ results in a significant reduction in weight gain, thereby imparting improved oxidation resistance. The morphology of the oxides formed on the surface is analyzed using field emission scanning electron microscope and the phases are identified by X-ray diffraction studies. The major oxidation products formed on the surface of NiCrAlY and Ni10CoCrAlY coatings consist of NiO. In contrast, the surface of Ni40CoCrAlY coating comprises of predominantly CoO and small amount of NiCo₂O₄. Cobalt oxide (CoO) is formed as the major phase on the surface of the Ni60CoCrAlY coating. The grains on the surface of ZrO₂-modified NiCoCrAlY composites are faceted, while such grains are not seen in the case of unmodified coatings. The texture analysis reveals that cooling rate is the deciding factor for the facet formation. The coatings have been characterized extensively using X-ray photoelectron spectroscopy to get in-depth understanding.

中文翻译：

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电沉积氧化锆改性 NiCoCrAlY 复合涂层在 1000°C 等温氧化的表征

本研究的目的是评估电沉积氧化锆 (ZrO ₂ ) 改性 NiCoCrAlY 复合涂层在大气条件下1000 ^∘ C等温氧化24 小时。0、10、40和60的NiCoCrAlY复合涂层比较了钴含量的重量百分比。氧化研究表明，钇(Y)和ZrO ₂的掺杂导致重量增加显着减少，从而提高了抗氧化性。使用场发射扫描电子显微镜分析表面上形成的氧化物的形态，并通过 X 射线衍射研究确定相。NiCrAlY 和 Ni10CoCrAlY 涂层表面形成的主要氧化产物由 NiO 组成。相比之下，Ni40CoCrAlY 涂层的表面主要由 CoO 和少量 NiCo ₂ O ₄组成。在 Ni60CoCrAlY 涂层的表面上形成了氧化钴 (CoO) 作为主要相。_{ZrO 2}表面的晶粒- 改性 NiCoCrAlY 复合材料是刻面的，而在未改性涂层的情况下看不到这种晶粒。织构分析表明，冷却速度是刻面形成的决定因素。使用 X 射线光电子能谱对涂层进行了广泛的表征，以获得深入的了解。