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着重介绍了用Ｂｒｉｄｇｍａｎ方法生长的（１－ｘ）Ｐｂ（Ｍｇ１／３Ｎｂ２／３）Ｏ３－ｘＰｂＴｉＯ３（ＰＭＮ－ＰＴ）固溶体单晶在介电、压电、热释电性能及相变方面的一些特点：①异常高的压电常数ｄ３３（高达３０００ｐＣ／Ｎ以上），耦合系数ｋｔ（在０．６以上），ｋ３３（达０.９０），高的介电常数（高达５０００甚至更高），低的Ｑｍ值（约６０），热释电系数也较高．②强烈的各向异性．③随着ＰＴ含量的增加，系统的弛豫行为逐渐减弱，在ｘ～０．３３时，材料在室温下成为正常铁电体，但ＰＥ－ＦＥ相变并非正常铁电相变，表现为在Ｔ＞Ｔｍ时； ～Ｔ关系不遵守居里－外斯定律，而是遵守Ｓｍｏｌｅｎｓｋｉｉ的关系．该相变也明显地与弥散相变不同．这种行为可用无规场的观点加以解释． 对ＰＭＮ－ＰＴ陶瓷，其压电性能与最好的软性ＰＺＴ相似，而 和ｋ３１略大．
The characteristics of dielectric, piezoelectric, pyroelectric properties and phase transformation of (1-x) Pb (Mg1 / 3Nb2 / 3) O3-xPbTiO3 (PMN-PT) solid solution grown by Bridgman method are emphatically introduced : Abnormally high piezoelectric constant d33 (up to 3000 pC / N or more), coupling coefficient kt (above 0.6), k33 (up to 0.90), high dielectric constant (up to 5000 or higher), low Qm value (about 60), pyroelectric coefficient is also higher. ② strong anisotropy. (3) With the increase of PT content, the relaxation behavior of the system gradually decreases. At x ~ 0.33, the material becomes normal ferroelectric at room temperature, but the PE-FE phase transition is not normal ferroelectric phase transformation, T> Tm; the relationship of ~ T does not obey Curie-Weiss’s law, but obeys Smolenskii’s relation. This phase change is also clearly different from the dispersion phase change. This kind of behavior can be explained in terms of irregularities. For PMN-PT ceramics, the piezoelectric properties are similar to those of the best soft PZT, slightly larger than k31.