Hot corrosion behavior of the La2(Zr0.7Ce0.3)2O7 ceramic in molten V2O5 and a Na2SO4+V2O5 salt mixture
Hot corrosion behavior of the La2(Zr0.7Ce0.3)2O7 ceramic in molten V2O5 and a Na2SO4+V2O5 salt mixture
复制标题
La-2(Zr0.7Ce0.3)(2)O-7陶瓷在熔融V2O5和Na2SO4 V2O5盐混合物中的热腐蚀行为
DOI：
10.1016/j.jallcom.2016.07.257
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发表时间：
2016-12-25
影响因子：
6.2
通讯作者：
Dong, Hongying
中科院分区：
文献类型：
--
作者：
Yin, Yichuan;Ma, Wen;Dong, Hongying
研究了烧绿石结构的La-2(Zr0.7Ce0.3)(2)O-7陶瓷在800、900和1000℃下的热腐蚀行为。用X射线衍射仪、扫描电子显微镜和能谱分析了腐蚀后的La-2(Zr0.7Ce0.3)(2)O-7陶瓷的相组成和微观结构。在V2O5介质中，800℃、900℃和1000℃时，La-2(Zr0.7Ce0.3)(2)O-7陶瓷表面的主要腐蚀产物为(La，Ce)VO4和m-ZrO2，随着腐蚀温度的升高，腐蚀层厚度逐渐减小，腐蚀产物尺寸逐渐增大。对于Na2SO4+V2O5盐混合物，在800℃、900℃和1000℃时，La-2(Zr0.7Ce0.3)(2)O-7陶瓷表面的主要腐蚀产物是(La，Ce)VO4和tZrO(2)，在800℃腐蚀后，Na2SO4可能已经残留在陶瓷表面，并随着腐蚀温度的升高而完全反应。La-2(Zr0.7Ce0.3)(2)O-7陶瓷与熔融的V2O5或Na2SO4+V2O5盐混合物之间的化学反应是La-2(Zr0.7Ce0.3)(2)O-7陶瓷退化的主要腐蚀机制。与V2O5单独腐蚀相比，Na2SO4+V2O5混合盐中V2O5的浓度较低是形成t-ZrO2的重要原因。(C)2016爱思唯尔B.V.保留所有权利。
The hot corrosion behavior of the La-2(Zr0.7Ce0.3)(2)O-7 ceramic with a pyrochlore structure was evaluated at selected temperatures of 800, 900 and 1000 degrees C. The phase constituents and microstructure of the corroded La-2(Zr0.7Ce0.3)(2)O-7 ceramic were investigated by X-ray diffraction, scanning electron microscopy and energy dispersive spectrometry. The main corrosion products on the surface of the La-2(Zr0.7Ce0.3)(2)O-7 ceramic in V2O5 were (La,Ce)VO4 and m-ZrO2 at 800, 900 and 1000 degrees C, and the corrosion-layer thickness decreased whereas the size of the corrosion products increased gradually as the corrosion temperature increased. For the Na2SO4+V2O5 salt mixture, the main corrosion products were mainly (La, Ce)VO4 and tZrO(2) at 800, 900 and 1000 degrees C on the surface of the La-2(Zr0.7Ce0.3)(2)O-7 ceramic; Na2SO4 may have remained on the ceramic surface after corrosion at 800 degrees C and reacted completely with the increase of the corrosion temperature. The chemical reactions between the La-2(Zr0.7Ce0.3)(2)O-7 ceramic and molten V2O5 or Na2SO4+V2O5 salt mixture are the primary corrosion mechanisms for the degradation of the La-2(Zr0.7Ce0.3)(2)O-7 ceramic. The lower concentration of V2O5 in the Na2SO4+V2O5 salt mixture compared to the case of V2O5 corrosion alone is significantly responsible for the development of t-ZrO2. (C) 2016 Elsevier B.V. All rights reserved.