Synthesis Mechanism and High Temperature Chemical Stability of CaZrO3  

作　　者：ZHANG Guangyu WANG Ronglin LIU Yifan JI Yingying LIU Hui 

机构地区：[1]Key Laboratory of Inorganic Nonmetallic Materials of Hebei Province, College of Material Science and Engineering, North China University of Science and Technology

出　　处：《China's Refractories》2019年第3期27-32,共6页中国耐火材料（英文版）

基　　金：supported by Hebei Iron and Steel Joint Fund, China (No.E2014209273)

摘　　要：CaZrO3 powder was prepared using CaO,CaCO3 and Ca(OH)2 as calcium source,nano m-ZrO2 powder,micron m-ZrO2 powder,micron CaO partially stabilized ZrO2(Ca-PSZ)powder as zircon source,through high temperature solid reaction.Effect of the calcination temperature(800,900,1000,1100,1200,1300,1400,1500,and 1600℃)and the holding time(3,4,and 5 h)on the phase composition change was studied to research the synthesis mechanism.The synthesized CaZrO3 powder was mixed with CaO,MgO,Al2O3,Cr2O3,SiO2,and ZrO2 powder separately and fired at 1500℃for 3 h to prepare specimens to research the high temperature chemical stability of CaZrO3 with different reaction mediums.The results show that during the synthesis process,the CaZrO3 content does not always increase with the increasing calcination temperature or the prolonging holding time,CaZrO3 decomposes resulting from the diffusion of Ca2+and O2-in CaZrO3 to m-ZrO2 or c-ZrO2.At high temperatures,when CaZrO3 is in alkaline environment(such as environment containing CaO or MgO),the high temperature chemical stability is high,but when CaZrO3 is not in alkaline environment(such as environment containing Al2O3,Cr2O3,SiO2 or ZrO2),the high temperature chemical stability is low.CaZrO3 powder was prepared using CaO, CaCO3 and Ca（OH）2 as calcium source, nano m-ZrO2 powder, micron m-ZrO2 powder, micron CaO partially stabilized ZrO2（Ca-PSZ） powder as zircon source, through high temperature solid reaction. Effect of the calcination temperature（800, 900, 1 000, 1 100, 1 200, 1 300, 1 400, 1 500, and 1 600 ℃） and the holding time（3, 4, and 5 h） on the phase composition change was studied to research the synthesis mechanism. The synthesized CaZrO3 powder was mixed with CaO, MgO, Al+2O3, Cr+2O3, SiO2, and ZrO2 powder separately and fired at 1 500 ℃ for 3 h to prepare specimens to research the high temperature chemical stability of CaZrO3 with different reaction mediums. The results show that during the synthesis process, the CaZrO3 content does not always increase with the increasing calcination temperature or the prolonging holding time, CaZrO3 decomposes resulting from the diffusion of Ca2+ and O2-in CaZrO3 to m-ZrO2 or c-ZrO2. At high temperatures, when CaZrO3 is in alkaline environment（such as environment containing CaO or MgO）, the high temperature chemical stability is high, but when CaZrO3 is not in alkaline environment（such as environment containing Al+2O3, Cr+2O3, SiO2 or ZrO2）, the high temperature chemical stability is low.

关 键 词：calcium zirconate synthesis reaction phase composition ion diffusion MICROSTRUCTURE 

分 类 号：TQ132.32[化学工程—无机化工]