Production and characterization of Nd and Dy doped lanthanum zirconate-based thermal barrier coatings


Karabaş M.

Surface and Coatings Technology, vol.394, 2020 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 394
  • Publication Date: 2020
  • Doi Number: 10.1016/j.surfcoat.2020.125864
  • Journal Name: Surface and Coatings Technology
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Aerospace Database, Biotechnology Research Abstracts, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, INSPEC, Metadex, Civil Engineering Abstracts
  • Keywords: Lanthanum zirconate, Plasma spray, Thermal barrier coatings, Thermal conductivity
  • Hakkari University Affiliated: No

Abstract

In this study, thermal barrier coatings in (La0.7(Nd, Dy)0.3)2Zr2O7 compound were produced by the plasma spray method as a single and double layer with YSZ. Microstructure, X-ray diffraction analysis, thermal conductivity measurements in the temperature range of 25–805 °C, tensile adhesion strengths, and thermal cycle tests at 1250–1300 °C of the coatings were performed. It was observed that the thermal conductivity values of single-layer and double-layer coatings were lower than in the undoped lanthanum zirconate coating, and that thermal conductivity value increased with increasing temperature. According to thermal-cycle test results, the single-layer Dy, Nd doped lanthanum zirconate-based coating was damaged at 163 and 300 cycles respectively. There was no damage after 400 cycles in the double-layer coatings. The adhesion-strength values of single-layer coatings were lower than those of double-layer coatings. Such results imply that LDZ and LNZ ceramics can be top-layer materials on YSZ for a double-layer TBC system.