The (1-x)Bi(Mg2/3Nb1/3)O3-xPbTiO3 (BMN-PT) piezoelectric ceramics were fabricated by a traditional solid-reaction method. The crystal structures, the piezoelectric, dielectric and ferroelectric behaviors of BMN-PT ceramics were investigated as a function of the content of PbriO3. XRD results showed that a single perovskite structure was obtained in all ceramic samples. XRD patterns of the samples with PbTiO3 content x≥0.60 had two obvious divided peaks, which verified that the rhombohedral and tetragonal phase were coexisted. The morphotropic phase boundary (MPB) of BMN-PT material was located at x=0.60. The largest piezoelectric coefficient Kp (170 pC/N), remnant polarization Pr(31.4 μC/cm2), planar electromechanical coupling factor Kp (0.35) and the smallest coercive field Ec were obtained on 0.4BMN-0.6PT. The measurements of dielectric constant εr(T) dependencies showed that the maximum εr(T) temperature (Tm) increased with the increase of PbTiO3 content, and Tm was about 276℃ for the MPBrncomposition.%利用传统固相烧结法制备了Bi(Mg2/3Nb1/3)O3-PbTiO3(BMN-PT)压电陶瓷,分析了不同PbTiO3含量对BMN-PT压电陶瓷的晶体结构、介电、压电及铁电性能的影响.XRD结果表明:合成的BMN-PT陶瓷具有纯钙钛矿结构,并且在PbTiO3含量为x=0.60时,其组分的XRD图谱在衍射角2θ=45°出现明显的分峰,说明该组分相结构中存在三方和四方相的共存.压电铁电性能显示,BMN-0.60PT有最大的压电常数d33(～170pC/N)和平面机电耦合系数kp(0.35),最小的矫顽场Ec(29.4kV/cm)及最大的剩余极化Pr(31.4μC/cm2).确定了BMN-PT压电陶瓷的准同型相界(MPB)为PbTiO3含量x=0.60的组分.介电系数温谱表明介电系数峰值温度?随着PbTiO3含量的增大而升高,MPB组分的Tm约为276℃.
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