变晶相界晶体 M_(2y)^+(Pb_(1-x)Ba_x)_(1-y))Nb_2O_6的生长、结构和介电性能

Growth、Structure and Dielectric Properties of Morphotropic Phase Boundary Crystals PBN and MPBN

本文报道了M_(2y)^+((Pb_(1-x)Ba_x)_(1-y))Nb_2O_6变晶相界晶体系列中 Pb_(0.4)Ba_(0.6)BNb_2O_6,K_(0.1)Pb_(0.38)Ba_(0.57)Nb_2O_6和 Na_(0.1)Pb_(0.38)Ba_(0.57)Nb_2O_6三种铁电晶体的生长技术。利用 X 射线衍射方法分析了晶体结构。测量了晶体的介电常数。结果表明,三种晶体室温时,都属四方晶系点群4mm 对称性。它们的居里温度分别为397℃,389℃和437℃。室温介电常数分别为98,250和100。其中 Na 改性的晶体,铁电居里温度有显著提高,而介电常数没有明显变化。

The crystal growth techniques for Pb_(0.4)Ba_(0.6)Na_2O_6,K_(0.1)Pb_(0.38)Ba_(0.57)Nb_2O_6 and Na_(0.1)Pb_(0.38)Ba_(0.57)Nb_2O_6 are reported in this paper.The results of X-ray diffraction show that these crystal belong to the tetra- gonal tungsten bronze structure of the point group 4mm at room temperature.Their Curie temperatures are 397℃,389℃ and 437℃,respectively.At roomtemperature,their dielectric constants are 98、250 and 100 respectively.