Intermetallic Ti-Al-Cr based layers and zirconia topcoats deposited on gamma titanium aluminides for environmental protection
Research output: Contribution to journal › Research article › Contributed › peer-review
Contributors
Abstract
Intermetallic Ti-Al-Cr layers with small additions of Si, Zr, W, and Y were deposited on ?-TiAl specimens using magnetron sputtering. The oxidation behaviour of the coated γ-TiAl alloy was studied in the temperature range between 950 and 1000°C under cyclic oxidation conditions in air. Compared to the bare substrate material, the coatings exhibited higher oxidation resistance. During prolonged exposure the intermetallic layers degraded losing their capability to form a protective alumina scale. On coated ?-TiAl samples zirconia topcoats were deposited by electron beam physical vapour deposition. These thermal barrier coating systems exhibited lifetimes exceeding the maximum exposure length of 1000 1 h cycles at 950°C, but failed at 1000°C. Failure was caused by degradation of the bond coats resulting in spallation of the thermally grown oxides.
Details
Original language | English |
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Pages (from-to) | 497-502 |
Number of pages | 6 |
Journal | Advanced materials research |
Volume | 278 |
Publication status | Published - 4 Jul 2011 |
Peer-reviewed | Yes |
Keywords
ASJC Scopus subject areas
Keywords
- Intermetallic coatings, Oxidation, Oxide scale, Thermal barrier coatings, Ti-Al-Cr, TiAl