Intermetallic Ti-Al-Cr based layers and zirconia topcoats deposited on gamma titanium aluminides for environmental protection

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

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

OriginalspracheEnglisch
Seiten (von - bis)497-502
Seitenumfang6
FachzeitschriftAdvanced materials research
Jahrgang278
PublikationsstatusVeröffentlicht - 4 Juli 2011
Peer-Review-StatusJa

Schlagworte

ASJC Scopus Sachgebiete

Schlagwörter

  • Intermetallic coatings, Oxidation, Oxide scale, Thermal barrier coatings, Ti-Al-Cr, TiAl