LaMgAl11O19 Coating for Thermal Barrier Applications Produced by EB-PVD
Thursday, May 14, 2015: 10:30 AM
Room 102A (Long Beach Convention and Entertainment Center)
Dr. Armen Kuzanyan
,
Institute for Physical Research, National Academy of Sciences, Ashtarak, Armenia
Silva Petrosyan
,
Institute for Physical Research, National Academy of Sciences, Ashtarak, Armenia
Georgi Badalyan
,
Institute for Physical Research, National Academy of Sciences, Ashtarak, Armenia
Astghik Kuzanyan
,
Institute for Physical Research, National Academy of Sciences, Ashtarak, Armenia
Prof. Vassilis Stathopoulos
,
Technological Educational Institute of Sterea Ellada, Psachna Chalkida, Greece
Lanthanum magnesium hexaaluminate (LaMgAl
11O
19) is a promising material as ceramic topcoat (TC) of high temperature thermal barrier coatings due to its low thermal conductivity, high thermal expansion and high thermal stability. It is well known that the electron-beam physical vapor deposition (EB-PVD) coating possessed a feathery microstructure with vertical separations that offer excellent compliance to thermal cycling. As a result TC obtained by EB-PVD exhibit enhanced durability under aero-engine thermal loading situations.
In this work LaMgAl11O19 was developed as a TC by EB-PVD. The complex structure of LaMgAl11O19 makes it difficult to realize by conventional EB-PVD and requires careful adjustment of deposition parameters.
For LaMgAl11O19 deposition it is necessary to solve the problem of mismatch of the target and TC composition, which is the result of a significantly high speed of Mg evaporation compared with the evaporation speed of La and Al. This presentation will discuss the possibility of obtaining stoichiometric coatings of LaMgAl11O19 by varying target composition and deposition parameters.
The work is performed in the frame of grant №310750 «THEBARCODE - Development of multifunctional Thermal Barrier Coatings and modeling tools for high temperature power generation with improved efficiency» FP7-NMP-2012-SMALL-6.
