Effect of Ta2O5 addition on thermophysical and mechanical properties of (Sm0.5Gd0.3Yb0.2)2Ce2O7 compounds. Issue 17 (1st December 2019)

• Record Type: Journal Article
• Authors: Zhao, Yongtao; Zhang, Junhui; Zhang, Hongsong; Fei, Wang; Chen, Xiaoge; Yang, Xianfeng
• Is Part Of: Ceramics international. Volume 45:Issue 17(2019)Part A
• Page Start: 21341
• Page End: 21347
• Publication Date: 2019-12-01
• Subjects: Thermal barrier coatings -- Ta2O5 addition -- Thermophysical properties -- Mechanical properties; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2019.07.120
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: In this study, the (Sm0.5 Gd0.3 Yb0.2 )2 (Ce1− x Ta x )2 O7+x oxides were obtained by high-temperature solid-state sintering. The phase lattice, micro-structure, thermal-physical and mechanical performances of samples were examined. The synthesised compounds exhibit a single fluorite-type lattice, and they also have relatively dense microscopic structures. The differences in atomic weight and ionic radius between the solute and host kations enable a reduction of thermal conductivity of bulk samples. The reduced thermal expansion coefficient and the elevated elastic modulus are ascribed to the lower ion-radius of Ta 5+ compared to Ce 4+ . The addition of "soft" Ta2 O5 reduces the micro-hardness and increases the fracture toughness. The presented results herein provide an effective approach to ameliorate the fracture toughness of ceramics for thermal barrier coatings.