HighTemp5.1
Supporting Thermal Barrier Coatings By Detonation Spraying Versus Air Plasma Spraying: Assessment of Techniques and Layers Properties

Wednesday, June 18, 2014: 8:00 AM
Sun 4 (Gaylord Palms Resort )
Prof. Vassilis Stathopoulos , Technological Educational Institute of Sterea Ellada, Psachna Chalkida, Greece
Prof. Vladislav Sadykov , Boreskov Institute of Catalysis, Novosibirsk, Russia
Prof. Vladimir Ulianitsky , Lavrentyev Institute of Hydrodynamics, Novosibirsk, Russia
Dr. Ion Trusca , Plasma Jet s.r.l, Magurele-Ilfov, Romania
Dr. Oleg Smorygo , Powder Metallurgy Institute, Minsk, Belarus
Dr. Vitali Mikutski , Powder Metallurgy Institute, Minsk, Belarus
Mrs. Yulia Fedorova , Boreskov Institute of Catalysis, Novosibirsk, Russia
Dr. Tatiana Larina , Boreskov Institute of Catalysis, Novosibirsk, Russia
Mr. Zakhar Vinokurov , Boreskov Institute of Catalysis, Novosibirsk, Russia
Dr. Aleksei Salanov , Boreskov Institute of Catalysis, Novosibirsk, Russia
Dr. Vladimir Kriventsov , Boreskov Institute of Catalysis, Novosibirsk, Russia
Dr. Vladimir Stoyanovsky , Boreskov Institute of Catalysis, Novosibirsk, Russia
Prof. Vyacheslav Ivanov , Boreskov Institute of Catalysis, Novosibirsk, Russia
Development of new low-cost efficient methods of high quality thermal barriers deposition on hot section components of aero-propulsion systems (turbine blades etc) is a vital task for  aerospace industry. In this work, characteristics of thermal barrier coatings supported by detonation spraying (DS) and traditional air plasma spraying (APS) are compared. Particles of bond coat (NiCrAlY) and top-coat (YSZ) materials fed into hot gas streams as dry powders were deposited on planar Ni superalloy substrates. For DS computer –controlled CCDS2000 complex was used to provide strict control of combustion gases temperature, velocity  and composition produced by acetylene-oxygen mixture detonation, and, hence, deposition parameters. To avoid oxidation, bond coat was supported using reducing atmosphere, while top coat was supported in oxidizing conditions. Development of coatings texture, composition and real/defect structure after annealing under air up to 1200 oC as well as after series of thermal shocks up to 1000 oC were studied by combination of diffraction methods (high resolution SEM and TEM with EDX, in situ XRD on synchrotron radiation, EXAFS) and spectroscopic methods (UV-Vis, XPS, SIMS, laser-excited luminescence spectra). Both morphology, texture and real/defect structure of top-coat YSZ layers were found to be quite similar for both deposition methods being comprised of porous aggregates of partially melted  particles with some microcracks in between. Strong disordering of Zr coordination sphere in YSZ particles was revealed by EXAFS and UV-Vis. Thermal annealing does not change texture, microstructure and YSZ domain sizes, though some defects such as anion vacancies generated by deposition were annealed. Thermal shocks have not caused neither layers spallation not cracks between bond-coat and top-coat for both methods. Hence, highly –productive DS method providing characteristics of thermal barrier  coatings similar to that of dry APS method is suitable for this application.

Support by THEBARCODE project (№310750-FP7) is gratefully acknowledged.

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