中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
Vol. 25 No. 8 August 2015 |
(1. School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China;
2. Institute of New Materials, Guangzhou Research Institute of Non-ferrous Metals, Guangzhou 510650, China;
3. IRTES-LERMPS Laboratory, Université de Technologie de Belfort-Montbéliard, Belfort Cedex 90010, France)
Abstract:A columnar Al film was firstly deposited on the top of 7%Y2O3-stabilized zirconia (7YSZ) ceramic coating in thermal barrier coating (TBC) system by magnetron sputtering. A vacuum treatment was then carried out at 700 °C for 1 h and 900 °C for 5 h to improve the erosion resistance of Al-deposited TBC. A α-Al2O3 layer was in situ synthesized on the top of 7YSZ coating via vacuum heat treatment. The microstructure evolution of Al-deposited TBC illustrated that a loose surface-layer and a dense sub-layer formed on the top of 7YSZ coating after vacuum treatment. The phase structures of the as-sprayed TBC and the Al-deposited TBC after vacuum heat treatment were characterized by X-ray diffraction (XRD) and transmission electron microscope (TEM) assisted with focused ion beam (FIB). Particulate erosion resistances of the as-sprayed TBC and treated TBC were compared at room temperature. In addition, erosion mechanism and schematic diagram were proposed. The results show that the Al-deposited TBC after vacuum heat treatment has better particulate erosion resistance than the as-sprayed one.
Key words: thermal barrier coating; 7%Y2O3-stabilized zirconia (7YSZ); erosion resistance; in situ synthesis; α-Al2O3