Thermophysical performances of Sm2O3-doped Gd3TaO7 oxides for thermal barrier coatings. Issue 8 (July 2023)

• Record Type: Journal Article
• Authors: Sang, Weiwei; Zhang, Hongsong; Liu, Shuaixia; Zhang, Haoming; Ren, Bo; Tang, An; Chen, Xiaoge; Xie, Wenbo; Hou, Ruiyi; Ma, Hongjun; Li, Siqi
• Is Part Of: Journal of the European Ceramic Society. Volume 43:Issue 8(2023)
• Page Start: 3676
• Page End: 3683
• Publication Date: 2023-07
• Subjects: Thermal barrier coatings -- Rare-earth tantalate oxides -- Thermophysical performances -- Lattice steadiness; Ceramic materials -- Periodicals; Composite materials -- Periodicals; Matériaux céramiques -- Périodiques; Composites -- Périodiques; Ceramic materials; Composite materials; Periodicals; Electronic journals; 666.05
• DOI: 10.1016/j.jeurceramsoc.2023.01.060
• Languages: English
• ISSNs: 0955-2219

Abstract

Abstract: To investigate the effect of Sm3 O3 addition on the thermophysical performances of Gd3 TaO7, (Gd1−x Smx )3 TaO7 oxides were synthesised using sol-gel and sintering with high-temperature technologies, and their thermophysical properties were researched. The investigations exhibit that the obtained powders comprise well-distributed particles, and the bulk specimens have densified microstructures. The obtained ceramics have single pyrochlore-lattice. Owing to varied scattering strength coefficient of phonon caused by the differences in ionic radius and mass between the substituting and substituted elements, the value of thermal conductivity of (Gd1−x Smx )3 TaO7 decreases firstly and further increases with the increase fraction of Sm2 O3 . The coefficient of thermal expansion of (Gd1−x Smx )3 TaO7 is ameliorated owing to the higher ionic radius of Sm 3+ than Gd 3+ . Except for Sm3 TaO7, the synthesised ceramics display outstanding lattice steadiness up to 1400 °C. Highlights: The (Gd1−x Smx )3 TaO7 oxides were prepared by a modified sol-gel technique and high-temperature sintering method. The obtained oxides have single pyrochlore-type lattice, and no element is lost during high-temperature calcination. The (Gd1−x Smx )3 TaO7 oxides have low thermal conductivity and high expansion coefficient. Except for Sm3 TaO7, the obtained oxides are of excellent phase-stability up to 1400 °C. The (Gd1−x Smx )3 TaO7 oxides can be used as candidate for thermal barrier coatings.