优化的B位离子氧化物共烧法制备钙钛矿结构的PYN-PZN-PT三元铁电陶瓷

New Pb(Yb_(1/2)Nb_(1/2))O_3-Pb(Zn_(1/3)Nb_(2/3))O_3-PbTiO_3 ternary ferroelectric solid solution prepared by a modified B-site oxides co-calcining method

通过优化B位离子氧化物共烧方法，成功制备出具有纯钙钛矿结构的Pb（Yb1/2Nb1／2）O3-Pb（Zn1／3Nb2／3）O3—PbTiO3（PYN-PZN-PT）三元铁电固溶体陶瓷，有效地抑制PZN基陶瓷制备过程中烧绿石相的形成．选取（0．48-x）PYN-0．52PZN-xPT（x=0．24～0．28），对三元体系的相结构、铁电、压电和介电性能进行了研究．结果表明：烧结得到的陶瓷致密均匀无杂相，晶粒尺寸2～4μm；随着PT含量的增加，物相经历了从三方相到三方和四方相共存的准同型相界（MPB）、再到四方相的结构演变；MPB附近的组分具有优异的性能，性能最好的组分是0．21PYN-0．52PZN-0．27PT，其压电系数d33—550pC／N，室温介电常数ε′=2070，矫顽场Ec=19．9kV／cm，居里温度Tc=260℃；陶瓷样品的介电温谱表现出介电弥散以及介电峰的展宽等类弛豫体的特点．

New relaxor ferroelectric system Pb （Yb1/2 Nb1/2 ） O3-Pb （ Zn1/3 Nb2/3 ） O3-PbTiO3 with pure perovskite structure was synthesized using a modified B-site oxides co-calcining precursor method, which can effectively suppress the pyrochlore phase. The structure, dielectric, piezo-/ferroelectric properties for （0. 48-x）PYN-0. 52PZN-xPT with x = 0. 24 - 0. 28 had been systematically investigated. The ceramic sample exhibits good sintering behavior with dense and homogeneous characteristics. The average grain size was found to be 2 - 4 μm.With increasing of PT concentration, an obvious structural development of rhombohedral to tetragonal phase and a MPB region were determined using XRD results. The compositions within MPB region exhibit relatively high values of the electric properties. The optimal piezoelectric and dielectric properties were achieved for MPB composition 0. 21PZN-0. 52PYN-0. 27PT with ε′≈2 070, d33 ≈ 550 pC/N, Tc≈260℃, Ec≈19.9 kV/cm. The dielectric response of the ternary system shows a relaxor-like behavior with broad dielectric peaks and dispersive dielectric behavior with respect to frequency. The results indicate that the PYN-PZN-PT ternary system may be a promising candidate for high operating temperature and high power application in electromechanical coupling field.