J. Mater. Sci. Technol. ›› 2015, Vol. 31 ›› Issue (10): 1006-1010.DOI: 10.1016/j.jmst.2015.06.002

• Orginal Article • Previous Articles     Next Articles

Reaction Mechanism and Thermal Insulation Property of Al-deposited 7YSZ Thermal Barrier Coating

Xiaofeng Zhang1, 2, Kesong Zhou1, 2, *, Wei Xu1, 2, Jinbing Song2, Chunming Deng2, Min Liu2   

  1. 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
  • Received:2014-09-03 Revised:2014-10-17
  • Contact: * Corresponding author. Prof.; Tel.: +86 20 37238263; Fax: +86 20 37238531.E-mail address: kszhou200404@163.com (K. Zhou).
  • Supported by:
    This work was supported by the National Basic Research Program of China (“973” program, No. 2012CB625100) and the National High-tech Research and Development Program of China (“863” program, No. 2012AA03A512).

Abstract: To increase the performance and efficiency of thermal barrier coating (TBC), it is important to improve the thermal insulation property. In this work, a columnar Al film was deposited at the top of 7 wt% yttria-stabilized zirconia (7YSZ) TBC by magnetron sputtering. A vacuum heat treatment was then carried out to improve the insulation property of Al-deposited TBC. Reaction mechanism of Al-ZrO2 system in Al-deposited TBC was studied by differential thermal analysis (DTA). The phase structures of the as-sprayed TBC, the Al-deposited and vacuum-treated TBC were characterized. The microstructure evolution of Al-deposited TBC was illustrated after vacuum heat treatment. And the insulation property of the as-sprayed TBC and treated TBC was compared. The results show that a multi-scaled layer, consisting of micron/nano structured α-Al2O3 and Al3Zr grain was in situ synthesized at the top of 7YSZ coating via vacuum heat treatment. The TBC with the multi-scaled overlay has better insulation property than the as-sprayed TBC.

Key words: Thermal barrier coating, Al deposition, Insulation property, α, -alumina