Effect Of Microstructure And Properties Of TBC Produced By Electrophoretic Deposition

YSZ/(Al, Ni) composite coatings were synthesized on the substrate of Inconel 600 superalloy by electrophoretic deposition technology. The microstructure and properties of YSZ/(Al,Ni)composite coatings with ball peeling treatment of substrate was researched.Besides, Effect of rare earth doped Nd2O3 and Gd2O3 on Microstructure and properties of YSZ/(Al, Ni)composite coatings were also investigated.Compared with YSZ/(Al, Ni) composite coatings without ball peeling of substate, the results show that the ball peeling coated samples exhibit an excellent adherence to the substrate without cracks or spallation. The EDS mapping analysis indicated that an obvious outward diffusion of Cr from the substrate to interface was occurred after isothermal oxidation. After isothermal oxidation in air at 1100℃ for 100 h, Cr diffused into the ball peeling and unprocessed coated samples to a depth of about 4.0 μm and 2.91 μm,respectively. Compared to YSZ/(Al, Ni) composite coatings without ball peeling of substrate, the adhesion strength and high temperature oxidation of the coatings was tested and the experimental data showed the superior adhesion and oxidation resistance of YSZ/(Al, Ni) composite coatings with ball peeling.The results showed that, G-YSZ/(Al, Ni)composite coatings have a little of growth of grain and the surface of the coating is more dense and crack-less. The adhesion strength of G-YSZ/(Al, Ni) and YSZ/(Al, Ni) after isothermal oxidation in air at 1100℃ for 100 h,were 3.5 N and 2.6 N, respectively. G-YSZ/(Al, Ni) composite coatings exist Gd2Zr2O7 and stable NiAl2O4 phases by XRD analysis, and Gd2Zr2O7 phase has a good stability and resistance to high temperature oxidation. G-YSZ/(Al, Ni) composite coatings significantly improve the oxidation resistance during isothermal oxidation in air at 1100 ℃. After isothermal oxidation in air at 1100 ℃, G-YSZ/(Al, Ni) composite coating has a better adhesion strength between substrate, the spalling resistance and service life is better.Compared with YSZ/(Al, Ni) composite coatings without rare earth doped,N-YSZ/(Al, Ni) composite coatings have a little of growth of grain and the surface of the coating is more dense and crack-less. The adhesion strength of N-YSZ/(Al, Ni) afterisothermal oxidation in air at 1100℃for 100 h, was 3.26 N. After isothermal oxidation in air at 1100℃, N-YSZ/(Al, Ni) composite coatings has a better adhesion strength between substrate, the spalling resistance and service life is better. Compared with YSZ/(Al, Ni)composite coatings, N-YSZ/(Al, Ni) composite coatings significantly improve the oxidation resistance during isothermal oxidation in air at 1100℃.