Synthesis And Research Of Electromechanical Properties Of Mn-doped Pb(In_1/2Nb_1/2)O₃-Pb(Mg_1/3Nb_2/3)O₃-PbTiO₃Piezoelectric Ceramic

Pb(In_1/2Nb_1/2)O₃-Pb(Mg_1/3Nb_2/3)O₃-PbTiO₃（PIN-PMN-PT） ternary piezoelectricceramics sprang up gradually in recent years, which has excellent piezoelectricproperties, dielectric properties and electrical properties，in addition, has higherCurie temperature and the phase transition temperature. These excellent propertieswill make PIN-PMN-PT piezoelectric ceramic，for a long time, to become animportant component of piezoelectric material in the future. As a "hard doping",Mn-doped can enhance the mechanical quality factor greatly, lower the dielectricloss （of piezoelectric materials） and significantly improved mechanical andelectrical performance of piezoelectric material. But the Mn-doped PIN-PMN-PTpiezoelectric ceramics hadn’t the literatures so far. Therefore the in-depth andsystematic research of Mn-doped PIN-PMN-PT piezoelectric ceramic is especiallyimportant.Firstly, this paper researches the preparation process of PIN-PMN-PTceramics and summarizes the best preparation condition of two precursors,InNbO4and MgNb2O6, is1100°C-7h and1000°C-7h-5°C/min. And the bestpreparation condition of PIN-PMN-PT piezoelectric ceramic is1250°C-6h. Afterthat, we make three different components of the ceramic in MPB. Moreover, wecompare the performance of different components and summarize the law of thePIN-PMN-PT ceramic. We find that58PIN-8PMN-34PT which has higher contentof PIN component reflects the better temperature properties Tc=289°C and thepiezoelectric properties d₃₃=438pC/N. When PMN component contented higher, thepiezoelectric properties of6PIN-60PMN-34PT increased to d₃₃=550pC/N, but thetemperature properties Tc=170°C is lower. The component of24PIN-42PMN-34PT has the best comprehensive performance: d₃₃=516pC/N，Tc=205°C，Kp=0.67，Qm=68.34， tan δ （%）=1.67. Hence, this paper takes thiscomponent to implement the Mn-doped experiments.This paper studied the properties of24PIN-42PMN-34PT piezoelectricceramic doped different proportions of Mn, like ferroelectric, dielectric,piezoelectric and electromechanical properties. We find that Mn-doped iscontributed to the sintering and crystallization of24PIN-42PMN-34PTpiezoelectric ceramic. And Mn-doped24PIN-42PMN-34PT piezoelectric ceramicreflects acceptor doping characteristics: the electrical and mechanical performance increase, however, the ferroelectric and piezoelectric properties decrease. Throughthe experimental research, we find the optimum ratio of doping Mn in24PIN-PMN-PT piezoelectric ceramics is between1mol%and2mol%. Whendoping ratio is1mol%, the change of24PIN-42PMN-34PT piezoelectric ceramicin performance is as followed:Qm increases1547.56%, tan δ decreases82.22%,Kpdecreases17.91%and d₃₃decreases16.67%。When doping ratio is2mol%,Qmincreases2231.46%, tanδ decreases63.89%, Kpdecreases15.7%and d₃₃decreases32.75%. Taking the comprehensive performance into consideration,Mn-doped PIN-PMN-PT piezoelectric ceramic has an extremely high mechanicalquality factor and low dielectric loss, it will have a wide application in ultrasonicmedical imaging and power ultrasound.