采用二次合成法制备了纯相钙钛矿结构三元(0.7-x)Pb(Lu1/2Nb1/2)O3-0.3Pb(Mg1/3Nb2/3)O3-xPbTiO3(PLNPMN-PT)(0.38≤x≤0.46)压电陶瓷,研究了准同型相界(MPB)附近组分的介电、压电和铁电性能。XRD分析表明PLN-PMN-PT存在准同型相界,且准同型相界区域大致为0.40≤x≤0.44。MPB附近组分为0.29PLN-0.3PMN-0.41PT陶瓷具有较高的居里温度和相变温度,分别为270℃和135℃,同时该组分表现出较好的铁电压电性能,压电系数达到460 pC/N,矫顽场为14.8 kV/cm,剩余极化强度Pr为34.6μC/cm^2。PLN-PMN-PT材料在压电领域具有潜在的应用前景。
Ceramics of (0.7-x)Pb(Lul/2Nb1/2)O3-O.3Pb(Mg1/3Nb2/3)O3-xPbTiO3(PLN-PMN-PT) (0.38 ≤ x ≤ 0.46) ternary system were synthesized by means of a two-step columbite precursor method which can effectively suppress the pyrochlore phase. A morphotropic phase boundary (MPB) region in the ternary systems was found in the range of 0.40 ≤ x ≤0.44 and the electric properties of the compositions near MPB region were investigated. Those compositions within MPB exhibit good comprehensive piezoelectric properties. The ceramic with composition of 0.29PLN- 0.3PMN-0.41PT shows a high Curie temperature of 270℃ and a high rhombohedral-tetragonal phase transition tem- perature of 135℃, whose piezoelectric coefficient d33, coercive field Ec and remnant polarization Pr are found to be 460 pC/N, 14.8 kV/cm and 34.6 μC/cm2, respectively. The large coercive field and high To enable it a promising candidate for application in the piezoelectricity field.