Oxidation behavior of thermal barrier coating systems with Al interlayer under isothermal loading

20th Chemnitz Seminar on Materials Engineering - 20. Werkstofftechnisches Kolloquium

Ali, I.^1 ; Sokolowski, P.^2,3 ; Grund, T.^1 ; Pawlowski, L.^2 ; Lampke, T.^1

Institute of Materials Science and Engineering, Chemnitz University of Technology, Chemnitz, Germany^1

Institut de Recherche sur les Céramiques IRCER, University of Limoges, Limoges, France^2

Faculty of Mechanical Engineering, Wroclaw University of Technology, Wroclaw, Poland^3

关键词: Atmospheric plasmas;    Dc magnetron sputtering;    Isothermal exposures;    Isothermal loading;    Oxidation behaviors;    Thermal barrier coating systems;    Thermally grown oxide;    Yttria-stabilized zirconias (YSZ);   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/373/1/012010/pdf
DOI  :  10.1088/1757-899X/373/1/012010

来源: IOP

【 摘 要 】

In the present study, the phenomena related to the Thermally Grown Oxides (TGO) in atmospheric plasma sprayed Thermal Barrier Coatings (TBCs) are discussed. CoNiCrAlY bond coatings were sprayed on Inconel 600 substrates. Subsequently, thin Al layers were deposited by DC-Magnetron sputtering. Finally, yttria-stabilized zirconia (YSZ) top coatings were deposited to form a three-layered TBC system. The thus produced aluminum interlayer containing thermal barrier coatings (Al-TBC) were subjected to isothermal exposure with different holding times at 1150 °C and compared with reference TBCs of the same kind, but without Al interlayers (R-TBC). The oxide film formation in the interface between bond coating (BC) and top coating (TC) was investigated by scanning electron microscope (SEM) after 100 and 300 h of high temperature isothermal exposure. The growth of this oxide film as a function of the isothermal exposure time was studied. As a result, the designed Al-TBC system exhibited better oxidation resistance in the BC/TC interface than the two-layered R-TBC system. This was lead back to the Al enrichment, which slows down the formation rate of transition metal oxides during thermal loading.