1. Multilayer GZ/YSZ Thermal Barrier Coating from Suspension and Solution Precursor Plasma Spray
- Author
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Leng, Kah, Romero, Acacio Rincon, and Hussain, Tanvir
- Subjects
Physics - Applied Physics ,Condensed Matter - Materials Science - Abstract
Gas turbines rely on thermal barrier coating (TBC) to thermally insulate the nickel-based superalloys underneath during operation; however, current TBCs, yttria stabilised zirconia (YSZ), limit the operating temperature and hence efficiency. At an operating temperature above 1200{\deg}C, YSZ is susceptible to failure due to phase instabilities and CMAS (Calcia-Magnesia-Alumina-Silica) attack. Gadolinium zirconates (GZ) could overcome the drawback of YSZ, complementing each other with the multi-layer approach. This study introduces a novel approach utilising axial suspension plasma spray (ASPS) and axial solution precursor plasma spray (ASPPS) to produce a double-layer and a triple-layer TBCs with improved CMAS resistance. The former comprised suspension plasma sprayed GZ and YSZ layers while the latter had an additional dense layer deposited through a solution precursor to minimise the columnar gaps that pre-existed in the SPS GZ layer, thus resisting CMAS infiltration. Both coatings performed similarly in furnace cycling test (FCT) and burner rig testing (BRT). In the CMAS test, triple-layer coating showed better CMAS resistivity, as evidenced by the limited CMAS infiltration observed on the surface., Comment: 42 pages, 14 figures
- Published
- 2023