TY - JOUR
T1 - Preparation and thermophysical properties of (Sm0.5La0.5)2Zr2O7 and (Sm0.5La0.5)2 (Zr0.8Ce0.2)2O7 ceramics for thermal barrier coatings
AU - Hong-song, Zhang
AU - Qiang, Xu
AU - Fu-chi, Wang
AU - Ling, Liu
AU - Yuan, Wei
AU - Xiaoge, Chen
PY - 2009/5/5
Y1 - 2009/5/5
N2 - Two kinds of rare earth zirconate (Sm0.5La0.5)2Zr2O7 and (Sm0.5La0.5)2(Zr0.8Ce0.2)2O7 ceramics were prepared by solid state reaction at 1600 °C for 10 h. The phase compositions and microstructures, thermophysical properties of these materials were investigated. XRD results revealed that single phase (Sm0.5La0.5)2Zr2O7 and (Sm0.5La0.5)2(Zr0.8Ce0.2)2O7 with pyrochlore structure were synthesized. The SEM results showed that the microstructures of these materials were dense and no other phases existed among the particles. With the temperature increasing, the thermal expansion coefficient (TEC) of the ceramic increased, while the thermal conductivity decreased. The thermal expansion coefficients of (Sm0.5La0.5)2Zr2O7 and (Sm0.5La0.5)2(Zr0.8Ce0.2)2O7 are lower than that of Sm2Zr2O7, the addition of CeO2 resulted in a higher thermal expansion coefficient of (Sm0.5La0.5)2(Zr0.8Ce0.2)2O7 than that of 8YSZ and (Sm0.5La0.5)2Zr2O7. However, the thermal expansion coefficient of (Sm0.5La0.5)2Zr2O7 is lower than that of 8YSZ, it still fulfills the basic requirement of thermal barrier coatings. The thermal conductivities of (Sm0.5La0.5)2Zr2O7 and (Sm0.5La0.5)2(Zr0.8Ce0.2)2O7 are much lower than that of Sm2Zr2O7 because of the phonon scattering resulted by the doping of La2O3 or CeO2, and the thermal conductivity of (Sm0.5La0.5)2(Zr0.8Ce0.2)2O7 is lower than of (Sm0.5La0.5)2Zr2O7. These results imply that (Sm0.5La0.5)2Zr2O7 and (Sm0.5La0.5)2(Zr0.8Ce0.2)2O7 have potentials to be used as novel candidate materials for thermal barrier coatings in the future.
AB - Two kinds of rare earth zirconate (Sm0.5La0.5)2Zr2O7 and (Sm0.5La0.5)2(Zr0.8Ce0.2)2O7 ceramics were prepared by solid state reaction at 1600 °C for 10 h. The phase compositions and microstructures, thermophysical properties of these materials were investigated. XRD results revealed that single phase (Sm0.5La0.5)2Zr2O7 and (Sm0.5La0.5)2(Zr0.8Ce0.2)2O7 with pyrochlore structure were synthesized. The SEM results showed that the microstructures of these materials were dense and no other phases existed among the particles. With the temperature increasing, the thermal expansion coefficient (TEC) of the ceramic increased, while the thermal conductivity decreased. The thermal expansion coefficients of (Sm0.5La0.5)2Zr2O7 and (Sm0.5La0.5)2(Zr0.8Ce0.2)2O7 are lower than that of Sm2Zr2O7, the addition of CeO2 resulted in a higher thermal expansion coefficient of (Sm0.5La0.5)2(Zr0.8Ce0.2)2O7 than that of 8YSZ and (Sm0.5La0.5)2Zr2O7. However, the thermal expansion coefficient of (Sm0.5La0.5)2Zr2O7 is lower than that of 8YSZ, it still fulfills the basic requirement of thermal barrier coatings. The thermal conductivities of (Sm0.5La0.5)2Zr2O7 and (Sm0.5La0.5)2(Zr0.8Ce0.2)2O7 are much lower than that of Sm2Zr2O7 because of the phonon scattering resulted by the doping of La2O3 or CeO2, and the thermal conductivity of (Sm0.5La0.5)2(Zr0.8Ce0.2)2O7 is lower than of (Sm0.5La0.5)2Zr2O7. These results imply that (Sm0.5La0.5)2Zr2O7 and (Sm0.5La0.5)2(Zr0.8Ce0.2)2O7 have potentials to be used as novel candidate materials for thermal barrier coatings in the future.
KW - Thermal barrier coatings
KW - Thermal conductivity
KW - Thermal expansion coefficient
KW - Zirconate
UR - http://www.scopus.com/inward/record.url?scp=63649119699&partnerID=8YFLogxK
U2 - 10.1016/j.jallcom.2008.07.068
DO - 10.1016/j.jallcom.2008.07.068
M3 - Article
AN - SCOPUS:63649119699
SN - 0925-8388
VL - 475
SP - 624
EP - 628
JO - Journal of Alloys and Compounds
JF - Journal of Alloys and Compounds
IS - 1-2
ER -