Microstructures and Properties of Sm-2(Zr0.7Ce0.3)(2)O-7/8YSZ Double-Ceramic-Layer Thermal Barrier Coatings Deposited by Atmospheric Plasma Spraying

Huo, Panjie; Song, Wenjia; Zhou, Xin; Zhang, Hao; Jiang, Jianing; Dong, Shujuan; Cao, Xueqiang und Dingwell, Donald B. (2019): Microstructures and Properties of Sm-2(Zr0.7Ce0.3)(2)O-7/8YSZ Double-Ceramic-Layer Thermal Barrier Coatings Deposited by Atmospheric Plasma Spraying. In: Journal of Thermal Spray Technology, Bd. 28, Nr. 5: S. 986-999

Abstract

The properties of Sm-2(Zr0.7Ce0.3)(2)O-7 (SZ7C3) as a novel thermal barrier coating (TBC) candidate have been evaluated. There is no evidence for a phase transformation for SZ7C3 from room temperature to 1600 degrees C. SZ7C3 exhibits a higher sintering resistance than the conventional yttria-stabilized zirconia (YSZ). The Vickers hardness for the SZ7C3 bulk is ca. 9.6GPa, and the fracture toughness lies in a range of 1.5-2.5MPam(1/2). Single SZ7C3 coatings and SZ7C3/8YSZ double-ceramic-layer (DCL) coatings were prepared by plasma spraying. The thermal conductivities of SZ7C3 coatings range from 0.4 to 0.6Wm(-1)K(-1) (significantly lower than those of 8YSZ). SZ7C3 coatings also exhibit moderate thermal expansion coefficients (TECs), near 10.8x10(-6)K(-1) at 1200 degrees C. The values of thermal expansion coefficients and fracture toughness are higher than those of La-2(Zr0.7Ce0.3)(2)O-7 (LZ7C3), which has been proposed as a promising high-temperature (>1250 degrees C) TBC candidate material. The thermal cycling lifetime of SZ7C3/8YSZ DCL coating is much longer than that of LZ7C3/8YSZ TBC as demonstrated by the furnace thermal cycling tests, further confirming that SZ7C3 coatings have great potential as high-temperature TBCs for use in the next generation of advanced engines.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Geowissenschaften > Department für Geo- und Umweltwissenschaften
• Themengebiete: 500 Naturwissenschaften und Mathematik > 550 Geowissenschaften, Geologie
• ISSN: 1059-9630
• Sprache: Englisch