现代技术陶瓷
現代技術陶瓷
현대기술도자
ADVANCED CERAMICS
2015年
2期
20-25
,共6页
共沉淀%纳米ZrO2 -8w t％ Y2 O3粉末%相转变%晶体生长行为
共沉澱%納米ZrO2 -8w t％ Y2 O3粉末%相轉變%晶體生長行為
공침정%납미ZrO2 -8w t％ Y2 O3분말%상전변%정체생장행위
Coprecipitation%ZrO2 -8w t％ Y2 O3 nanopow der%Phase evolution%Grain grow th be-havior
以ZrOCl2·8H2O和Y（NO3）3·6H2O为原料，采用共沉淀法合成纳米ZrO2－8wt％ Y2O3（8YSZ）陶瓷粉末。利用XRD ，SEM ，TEM 等方法研究纳米8YSZ粉末热处理后相结构、晶粒尺寸和形貌的变化，并分析纳米8YSZ粉末的晶体生长行为。结果表明：凝胶化反应的pH值（9（11）对纳米8YSZ粉末的相结构无明显影响，不同pH值合成的8YSZ纳米粉末在1000℃温度范围内热处理2 h后都始终保持单一的四方相结构，在1200℃热处理2 h后，仅有少量四方相转变为单斜相。随热处理温度的升高晶粒尺寸逐渐增大。由于晶体生长机制不同，纳米8YSZ粉末的晶粒生长活化能在低温区和高温区不同，均远低于微米级3YSZ材料的晶粒生长活化能（580 kJ／mol）。
以ZrOCl2·8H2O和Y（NO3）3·6H2O為原料，採用共沉澱法閤成納米ZrO2－8wt％ Y2O3（8YSZ）陶瓷粉末。利用XRD ，SEM ，TEM 等方法研究納米8YSZ粉末熱處理後相結構、晶粒呎吋和形貌的變化，併分析納米8YSZ粉末的晶體生長行為。結果錶明：凝膠化反應的pH值（9（11）對納米8YSZ粉末的相結構無明顯影響，不同pH值閤成的8YSZ納米粉末在1000℃溫度範圍內熱處理2 h後都始終保持單一的四方相結構，在1200℃熱處理2 h後，僅有少量四方相轉變為單斜相。隨熱處理溫度的升高晶粒呎吋逐漸增大。由于晶體生長機製不同，納米8YSZ粉末的晶粒生長活化能在低溫區和高溫區不同，均遠低于微米級3YSZ材料的晶粒生長活化能（580 kJ／mol）。
이ZrOCl2·8H2O화Y（NO3）3·6H2O위원료，채용공침정법합성납미ZrO2－8wt％ Y2O3（8YSZ）도자분말。이용XRD ，SEM ，TEM 등방법연구납미8YSZ분말열처리후상결구、정립척촌화형모적변화，병분석납미8YSZ분말적정체생장행위。결과표명：응효화반응적pH치（9（11）대납미8YSZ분말적상결구무명현영향，불동pH치합성적8YSZ납미분말재1000℃온도범위내열처리2 h후도시종보지단일적사방상결구，재1200℃열처리2 h후，부유소량사방상전변위단사상。수열처리온도적승고정립척촌축점증대。유우정체생장궤제불동，납미8YSZ분말적정립생장활화능재저온구화고온구불동，균원저우미미급3YSZ재료적정립생장활화능（580 kJ／mol）。
The ZrO2 - 8wt% Y2 O3 (8YSZ ) nanopowders are synthesized by coprecipitation process .The phase structure ,crystallite size and morphological characteristic of the 8YSZ nanopow‐ders heat -treated at different temperatures are investigated by XRD ,SEM and TEM .The grain growth behavior of 8YSZ nanopowders is also discussed .The results indicate that the pH value (be‐tween 9 and 11) of gelation reaction has no obvious effect on the phase structure of 8YSZ nanopow‐ders .When heat -treated below 1000°C for 2h ,the tetragonal phase can be stabilized in 8YSZ nanop‐owders prepared with different pH values ,and a little amount of tetragonal phase transforms to mon‐oclinic phase after heat -treatment at 1200℃ for 2h .The crystallite size of 8YSZ nanopowders increa‐ses with the heat -treatment temperature increasing .Due to different crystal grow th mechanisms , there is the difference in the activation energy for crystal grow th of nanocrystalline 8YSZ in low tem‐perature zone and high temperature zone ,and both of which are much lower than that (580 kJ/mol) reported for submicro/micron-sized 3YSZ .
