Characterization of Tetragonal-Monoclinic, Ferroelastic Transformation and Domain Boundaries in Zirconia-Alloyed Yttrium Tantalate
نویسندگان
چکیده
There is a continuous search for an alternative oxide material to the yttria-stabilized zirconia (7YSZ), which currently serves as the thermal barrier coating materials for turbine engines [1]. The new material should have low thermal conductivity, high temperature stability, and ferroelastic toughening as exhibited by the 7YSZ. Therefore in this study, the Y-Ta-Zr-O system was investigated. The zirconia-rich part of this ternary phase diagram is quite studied, however less is known of the compositions in the vicinity of the YTaO4 phase. The goal of this study is to characterize the microstructure evolution that accompanied the tetragonal-monoclinic transformation in YTaO4 alloyed with 0 to 20 mole% of ZrO2.
منابع مشابه
The tetragonal–monoclinic, ferroelastic transformation in yttrium tantalate and effect of zirconia alloying
Oxide compositions of equimolar YO1.5 and TaO2.5 in the Y–Ta–Zr–O system have attractive properties for high-temperature applications, including as thermal barrier coatings. The effect of zirconia concentration, from 0 to 20 mol.% cation, on the tetragonal-to-monoclinic phase transition has been studied using high-temperature X-ray diffraction, Raman spectroscopy and electron microscopy. The tr...
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