Akademska digitalna zbirka SLovenije - logo
E-resources
Peer reviewed Open access
  • Cyclic Hot Corrosion Failur...
    Ozgurluk, Yasin; Doleker, Kadir Mert; Ozkan, Dervis; Ahlatci, Hayrettin; Karaoglanli, Abdullah Cahit

    Coatings (Basel), 03/2019, Volume: 9, Issue: 3
    Journal Article

    The cold gas dynamic spray (CGDS) method has been considered a promising technology to produce a metallic bond coat for thermal barrier coating (TBC) systems. In this study, CoNiCrAlY bond coats produced by CGDS method were coated with yttria-stabilized zirconia (YSZ) by electron beam physical vapor deposition (EB-PVD). TBCs were subjected to 50 wt % V2O5 and 50 wt % Na2SO4 molten hot corrosion salt combinations at 1000 °C. In the case of YSZ top coat on TBCs, the reaction between Na2SO4, V2O5, and Y2O3 salts generates YVO4 crystals, and these structures cause the transformation of tetragonal ZrO2 to monoclinic ZrO2. This situation occurs under operating conditions that lead to TBC failure. Hot corrosion behavior and the related failure mechanisms of TBC systems were investigated and discussed using scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) analysis, and X-ray diffractometer (XRD).