In-situ fabrication of amorphous/eutectic Al2O3–YAG ceramic composite coating via atmospheric plasma spraying

Non‐isothermal crystallization kinetics of Al2O3‐YAG amorphous ceramic coating deposited via plasma spraying

“…In addition, the emerged weak crystalline diffraction peaks were identified to be α‐Al 2 O 3 and YAG phases. Thus, the coating was mainly composed of amorphous phases, which was in accordance with our previous results . Simultaneously, a few α‐Al 2 O 3 and YAG crystallites distributed in the coating matrix.…”

“…Simultaneously, a few α‐Al 2 O 3 and YAG crystallites distributed in the coating matrix. The nature of amorphous structure in the coating was further confirmed by Transmission electron microscopy (TEM) analysis in our previous study . The distribution of Al 2 O 3 and YAG microcrystallines can be evaluated via SEM accompanied with EDS analysis as shown in Figure .…”

“…Commercially available Al 2 O 3 (Wuxi Tuoboda Titanium White Products Co., LTD., China) and Y 2 O 3 (Ganzhou Cayon New Materials Co., LTD., China) powders (all of 4N) with D 50 of 76 and 74 nm were selected as feedstocks. The conventional spray drying process was carried out for the preparation of Al 2 O 3 /Y 2 O 3 sprayable powders in which contain nanostructure . The agglomerated powders were calcined at 1000~1100°C so as to remove the organic additives and improve the density of the granulated particles.…”

“…In our laboratory, a newly developed amorphous/eutectic Al 2 O 3 ‐YAG ceramic composite coating was in situ fabricated via atmospheric plasma spraying by means of ingenious design. It is worth emphasizing that in the as‐sprayed Al 2 O 3 ‐YAG composite coating, amorphous phase is dominant . Through heat treatment, a eutectic Al 2 O 3 ‐YAG ceramic coating with excellent hardness and high temperature microstructure stability was successfully obtained, which exhibited the microstructure consisting of 3 dimensional interlocking network of α‐Al 2 O 3 /YAG eutectic phases .…”

“…It is worth emphasizing that in the as‐sprayed Al 2 O 3 ‐YAG composite coating, amorphous phase is dominant . Through heat treatment, a eutectic Al 2 O 3 ‐YAG ceramic coating with excellent hardness and high temperature microstructure stability was successfully obtained, which exhibited the microstructure consisting of 3 dimensional interlocking network of α‐Al 2 O 3 /YAG eutectic phases . As a new amorphous ceramic coating, the thermal stability against crystallization and the strategy of controlled nucleation to obtain Al 2 O 3 ‐YAG amorphous/nano‐crystalline coating have become a crucial concern.…”