Effects of Er3+ doping on structure and thermal properties of (Sm1–Er )2Zr2O7 ceramics for thermal barrier coating

Rare earth Er 3+ doped (Sm 1– x Er x ) 2 Zr 2 O 7 ( x = 0.1, 0.2, and 0.3) ceramic samples were synthesized using a solid-state reaction method. The microstructure and thermal properties of these ceramics were investigated to evaluate their potential as thermal barrier coating materials. The results show that ceramics are compact with regular-shaped grains of 1–5 μm size. (Sm 1– x Er x ) 2 Zr 2 O 7 has a pyrochlore structure mainly determined by ionic radius ratio, but the ordering degree decreases with increase of the Er 2 O 3 content. There is no phase transformation from 1000 to 1200 °C, and the (Sm 1– x Er x ) 2 Zr 2 O 7 ceramics exhibit excellent phase stability during thermal treatment at 1200 °C for 100 h and 1400 °C for 50 h. The thermal conductivities of dense (Sm 1– x Er x ) 2 Zr 2 O 7 ceramics range from 1.52to 1.59 W/(m·K), which is lower than that of Sm 2 Zr 2 O 7 , and decrease as the Er 2 O 3 content increase. Besides, the thermal expansion coefficient of (Sm 1– x Er x ) 2 Zr 2 O 7 is higher than that of Sm 2 Zr 2 O 7 . The microstructure and thermal properties of Er 3+ doped Sm 2 Zr 2 O 7 ((Sm 1– x Er x ) 2 Zr 2 O 7 ( x = 0.1, 0.2, and 0.3)) ceramics synthesized by a solid-state reaction method were investigated. The (Sm 1– x Er x ) 2 Zr 2 O 7 ceramics exhibit excellent phase stability during thermal treatment at 1200 °C for 100 h and 1400 °C for 50 h. The thermal conductivities of (Sm 1– x Er x ) 2 Zr 2 O 7 ceramics are relatively lower than that of Sm 2 Zr 2 O 7 and decrease with increase of Er 2 O 3 content.