摘要
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（Mg1/3Nb2/3）O3-xPbTiO3（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.XRD 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 m increase accompanied by the irregular variation of the TC/Tm,the remnant polarization Pr increases,the coercive field Ec 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 m is 14070 and Tm is 148.2℃ at 1kHz,the value of d33 reaches 457pC/N,Pr is 14.69μC/cm2,and Ec is 4.72kV/cm.
出处
《陶瓷学报》
CAS
北大核心
2011年第4期540-547,共8页
Journal of Ceramics
基金
江苏省高校自然科学研究计划(编号:08KJB430001)
常州市科技局国际科技合作计划(编号:CZ2008014)
"青蓝工程"资助
