钙钛矿型铌锌酸铅陶瓷材料合成及其性能

Synthesis of Pb (Zn 0 7 Mg 0 3 ) 1/3 Nb 2/3 O 3 ceramics of perovskite structure and its dielectric performance

用Ｘ射线衍射和差热分析研究了铌锌酸铅Ｐｂ〔（Ｚｎ０．７Ｍｇ０．３）１／３Ｎｂ２／３〕Ｏ３陶瓷材料普通合成法和两种铌铁矿先驱体合成法的合成机理。研究表明，该材料的合成过程中，首先生成焦绿石相然后在较高温度生成钙钛矿相，先驱体法可以明显抑制焦绿石相的生成并使其反应温度向高温推迟，从而可以明显提高钙钛矿的产率。而简单先驱体法（ＰｂＯ＋ＺＮ＋ＭＮ）比复合先驱体法（ＰｂＯ＋ＺＭＮ）具有更好的合成效果。采用简单先驱体法通过合适的合成工艺可以制得钙钛矿含量大于９５％的Ｐｂ〔（Ｚｎ０．７Ｍｇ０．３）１／３Ｎｂ２／３〕Ｏ３陶瓷材料，其介电温谱具有明显的弥散性，为无序铁电陶瓷材料。研究发现，差热分析作为判断焦绿石和钙钛矿反应温度的重要依据，可以用于铌锌酸铅系陶瓷材料钙钛矿的合成研究。

The Synthetic mechanism of Pb (Zn 0 7 Mg 0 3 ) 1/3 Nb 2/3 O 3 ceramics by conventional and colubite precursor methods is studied by means of XRD and DTA The results show that in the synthesis, pyrochlore formed first, and then perovskite formed at rather higher temperature By colubite precursor method, the formation of pyrochlore would be restrained and the reaction temperature would rise higher; therefore, the content of perovskite would increase Better result can be achieved by simple colubite precursor method (PbO + ZN + MN) than by composite colubite precursor method (PbO + ZMN) Pb (Zn 0 7 Mg 0 3 ) 1/3 Nb 2/3 O 3 ceramics containing 95% or more perovskite is obtained by simple colubite precursor method and appropriate calcination process Diffuseness of permittivity temperature indicates that the ceramic belongs to disorder ferroelectric material It is found that DTA is efficient for studying synthesis of PZN system for its being able to determine the formation temperature of pyrochlore and perovskite (13 refs )