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Fabrication of Transparent La₂Zr₂O₇ by Reactive Spark Plasma Sintering

“…Conventional sintering such as pressureless sintering needed high sintering temperature (1873 K) to obtain less than 95% of the theoretical density [9]. Ion et al reported La 2 Zr 2 O 7 with a relative density of 97.9% after sintering at 1673 K for 10 h [11] and Ota et al reported 99.7% of 8 mol% Y 2 O 3 substituted La 2 Zr 2 O 7 body sintered at 1773 K by hot isostatic pressing for 2 h [3]. However, the starting powders were synthesized by a nitrate-modified alkoxide route and a hydrazine method with specific preheating and milling.…”

“…The absorption edge in the infrared range was 8.5 µm. Although fully dense La 2 Zr 2 O 7 bodies have been prepared by pressureless and hot isostatic pressing sintering [3,11], we first prepared transparent La 2 Zr 2 O 7 body by SPS using commercial powders.…”

“…Pyrochlore La 2 Zr 2 O 7 has received much attention on the synthesis and investigation of thermal barriers because of its excellent thermal stability, low thermal conductivity and high thermal expansion coefficient [1,2]. Moreover, studies on La 2 Zr 2 O 7 were carried out for ionic conductivity [3,4], catalytic properties [5] and possible application as a host of fluorescence centers [6,7]. La 2 Zr 2 O 7 powder has been prepared by many methods, such as solid-state reaction [8,9], sol-gel [10], nitric dissolution [6,11], coprecipitation-calcination [2] and hydrazine monohydration [3,4].…”

“…Moreover, studies on La 2 Zr 2 O 7 were carried out for ionic conductivity [3,4], catalytic properties [5] and possible application as a host of fluorescence centers [6,7]. La 2 Zr 2 O 7 powder has been prepared by many methods, such as solid-state reaction [8,9], sol-gel [10], nitric dissolution [6,11], coprecipitation-calcination [2] and hydrazine monohydration [3,4]. Among of them, the solid-state reaction is simple and convenient to prepare compound powders.…”

Experimental investigation and thermodynamic modelling in the ZrO2–La2O3–Y2O3 system

“…: +49 3731 393156; fax: +49 3731 393657. substitution of Zr by Y has opposite effect. Ota et al [10] synthesized pyrochlore (La 1−x Y x ) 2 Zr 2 O 7 with La 2 O 3 substituted by 8 mol% of Y 2 O 3 . The results of experimental studies by Andrievskaya and Red'ko [11] and Fabrichnaya et al [12] at 1250 • C showed that both La and Zr are substituted by Y in pyrochlore solid solution in the La 2 Zr 2 O 7 -Y 2 O 3 join up to 20 mol% of Y 2 O 3 in pyrochlore.…”