Oxidation resistance of γ-TiAl based alloy Ti-45Al-8Nb coated with intermetallic Ti-Al-Cr-Y layers and EB-PVD zirconia topcoats at 950°C in air

Research output: Contribution to journal › Research article › Contributed › peer-review

Contributors

  • Reinhold Braun - , German Aerospace Center (DLR) (Author)
  • Klemens Kelm - , German Aerospace Center (DLR) (Author)
  • Maik Fröhlich - , Kiel University (Author)
  • Christoph Leyens - , Institute of Materials Science, Chair of Materials Technology, German Aerospace Center (DLR), TUD Dresden University of Technology (Author)

Abstract

Samples of a high niobium bearing γ-TiAl based alloy were coated with intermetallic Ti-52Al-15Cr-0.4Y (in at.%) layers produced by magnetron sputtering. On some of the specimens thermal barrier coatings of 7. wt.% yttria partially stabilised zirconia were deposited using electron-beam physical vapour deposition. The oxidation behaviour of the coated Ti-45Al-8Nb (at.%) alloy with and without thermal protection was investigated at 950 °C under cyclic oxidation conditions in air. The 20 μm thick Ti-Al-Cr-Y layer exhibited excellent oxidation resistance at this exposure temperature associated with the formation of a thin continuous alumina scale. Lifetimes exceeding 1000. cycles of 1. h dwell time at 950 °C were determined for the TBC system consisting of zirconia topcoat and Ti-Al-Cr-Y bond coat.

Details

Original languageEnglish
Pages (from-to)128-134
Number of pages7
JournalSurface and Coatings Technology
Volume222
Publication statusPublished - 15 May 2013
Peer-reviewedYes

Keywords

ASJC Scopus subject areas

Keywords

  • Intermetallic coatings, Oxidation resistance, Oxide scale, Thermal barrier coatings, Titanium aluminides