摘要
以醋酸为水解催化剂和螯合剂,采用溶胶-凝胶法合成ZrO2-8%Y2O3(8YSZ)粉末,利用XRD、SEM方法研究纳米8YSZ粉末热处理后的相成分、晶粒尺寸和形貌的变化,并分析纳米8YSZ粉末中的晶粒生长行为。结果表明:溶剂中添加乙醇不利于纳米8YSZ粉末四方相(t)的稳定;在400～1200℃范围内,随着热处理温度的升高晶粒尺寸逐渐增大;然而纳米8YSZ粉末的晶粒生长活化能在低温区和高温区有所不同,热处理温度低于800℃时的晶粒生长活化能(9.71kJ/mol)明显小于热处理温度高于800℃时的晶粒生长活化能(43.06kJ/mol),这有利于t-8YSZ在低温下结晶,在高温下保持四方相的稳定性。
The ZrO2-8% Y2O3 （8YSZ） nanopowders are prepared by sol-gel process with AcOH as chelating agent and catalyst. The phase composition evolution, crystallite size and morphological characteristic of the 8YSZ powders after heat-treated at different temperatures are investigated by XRD and SEM. The grain growth behavior of 8YSZ nano-powder is discussed. The results indicate that the addition of ethanol in solvent is not beneficial for the stability of tetragonal phase in 8YSZ powders. With the temperature increasing from 400℃ to 1200℃, the crystallite size increases. However, there is the difference in the activation energy for crystal growth of nanocrystalline 8YSZ in low temperature zone and high temperature zone. Relatively, the activation energy in low temperature zone （9.71kJ/mol） is much lower than that in high temperature zone （43.06kJ/mol）, indicating that it is beneficial for t-8YSZ to crystallize at low temperature and maintain the stability of tetragonal phase at high temperature.
出处
《航空制造技术》
北大核心
2014年第6期122-125,131,共5页
Aeronautical Manufacturing Technology
