通过部分草酸盐工艺制备了颗粒尺寸较小、粒度分布较均匀、团聚较少的(1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3(PMN-PT)前驱体.以活性PMN-PT前驱体为原料,通过固相反应法制备PMN-PT陶瓷.XRD测量表明,通过部分草酸盐工艺制备的PMN-PT陶瓷中含有少量的焦绿石相.随着PbTiO3 (PT)含量的增加,PMN-PT陶瓷的晶体结构从三方铁电相逐渐向四方铁电相转变.烧成的PMN-PT陶瓷具有较高的致密度.组分和烧结温度对PMN-PT陶瓷的电学性能产生影响.随着烧结温度的升高,PMN-PT陶瓷的介电常数最大值εm增大,伴随着εm对应的温度Tc/Tm的不规律变化；剩余极化强度Pr增大,矫顽场Ec减小；压电应变常量d33值增大.随着PT含量的增加,Tc/Tm增大,介电响应特征从弥散型铁电相变向正常铁电相变转变,电滞回线从狭长的回线向接近矩形的形状转变.0.68PMN-0.32PT陶瓷呈现优良的综合电学性能,1200℃烧结的陶瓷1kHz时εm为14070,Tm为148.2℃,d33值为457pC/N,Pr为14.69μC/cm2,Ec为4.72kV/cm.%(1-x)Pb (Mg1/3Nba3)O3HIPbTiO3 (PMN-PT) precursor powders with smaller grain size, better size distribution and less conglomeration were prepared using the partial oxalate method. Then the active precursor powders as-obtained were used to prepare PMN-PT ceramics by the conventional solid-state reaction method. XRO measurement confirmed that all the sintered PMN-PT ceramics contain slight content of pyrochlore phase. With the increase of the content of PbTiO3 (PT), the crystal structure of the PMN-PT ceramics gradually changes from rhombohedral ferroelectric phase to tetragonal. The synthesized PMN-PT ceramics exhibit high relative density. Composition and sintering conditions exert great influences on the electrical properties of the sintered PMN-PT ceramics. With the increase of the sintering temperature, the dielectric constant and the Em increase accompanied by the irregular variation of the Tc/Tm the remnant polarization P, increases, the coercive field Em decreases, and the piezoelectric constant d33 increases. With the increase of the PT content, the Tc/Tm increases, the dielectric response changes with the ferroelectric phase transition from diffuse to normal, and the shape of the P-E hysteresis loops changes from a narrow loop to nearly a rectangle. The 0.68PMN-0.32PT ceramics sintered at 1200℃ exhibit excellent electrical properties, where Em is 14070 and Tm is 148.2℃ at 1kHz, the value of d33 reaches 457pC/N, P, is 14.69uC/cm2, and Ec is 4.72kV/cm.
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