Comparison of oxidation behavior of YSZ and Gd2Zr2O7 thermal barrier coatings (TBCs)

Döleker K. M., Karaoglanli A. C.

Surface and Coatings Technology, cilt.318, ss.198-207, 2017 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 318
  • Basım Tarihi: 2017
  • Doi Numarası: 10.1016/j.surfcoat.2016.12.078
  • Dergi Adı: Surface and Coatings Technology
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.198-207
  • Anahtar Kelimeler: Cold gas dynamic spray (CGDS), Gd2Zr2O7, Oxidation, Rare-earth oxides, Thermal barrier coating (TBC), YSZ
  • Ondokuz Mayıs Üniversitesi Adresli: Hayır

Özet

Yttria Stabilized Zirconia (YSZ) is widely used as a traditional ceramic top coat material in gas turbine engine components. Nowadays, rare earth zirconates, as alternative materials to YSZ, are enhanced for use as top coat layer of TBC owing to their better thermal isolation properties. In the present study, metallic CoNiCrAlY bond coat powder was sprayed on Inconel 718 superalloy substrate by cold gas dynamic spray (CGDS) technique. After the deposition of bond coats, YSZ and Gd2Zr2O7 top coats were produced using EB-PVD process. TBCs were exposed to isothermal oxidation tests at 1100 °C for 8, 24, 50 and 100 h. Oxidation and growth behaviors of thermally grown oxide (TGO) layer were observed. TBC samples were investigated using scanning electron microscope (SEM), EDS elemental mapping and X-ray diffractometer (XRD) analysis before and after the oxidation tests. Oxidation performances of two different TBC systems were compared to each other according to the analysis results.