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NiCrAlY coatings have been widely employed as the coatings to risist high temperature oxidation, hot corrosion and also the bond coat （BC） under thermal barrier coatings （TBCs）. High quality NiCrAlY coatings are currently always manufactured by means of physical vapor deposition （PVD）. This work prepared new NiCrAl nanocomposite coatings through electrodeposition of Ni into a porous CrAl nanoparticle layer pre-deposited electrophoretically on a metallic substrate. Microstructural observation shows that the as-deposited NiCrAl coatings, where the CrAl nanoparticles with the maximum mass percentage reaching 35 are uniformly dispersed, are dense and well bonded to the substrate. Oxidation in air at 1000 ℃ shows that the NiCrAl coatings can “smartly” grow a protective scale of either Cr2O3 or Al2O3, depending on the ratio of the content of Cr to Al which can be controlled during electrophoretic deposition. In the meantime, no spallation occurs even though the coatings oxidized for hundreds of hours.It is implying that the NiCrAl coatings are as good as the NiCrAlY coatings prepared by PVD in resistance to high temperature oxidation. This work paves a new way for manufacturing high quality NiCrAl（Y） coatings employed as overlay coat and BC, through electrodeposition with the merits of ease of fabrication and low cost as well as high efficiency.

High-performance gas turbines and aircraft engines necessitate MCrAlY (M = Ni, Co, or Ni/Co) coatings with exceptional oxidation resistance. Pre-heat-treatment can enhance the performance of MCrAlY bond coatings in the following ways: First, it reduces the porosity of the bond coating and promotes the diffusion of elements within it. Second, pre-heat-treatment allows for the formation of a continuous, dense, and moderately thick layer of pure Al2O3 scale, which helps to delay the formation of mixed oxides. Lastly, proper pre-heat-treatment can increase the grain size of the Al2O3 scale, leading to a lower growth rate of the oxide scale. Additionally, this article proposes new directions for developing more reasonable and effective pre-heat-treatment methods, laying the foundation for the creation of thermal barrier coatings (TBCs) with greater durability and higher performance. [ABSTRACT FROM AUTHOR]