交流电极化增强Pb(Mg_(1/3)Nb_(2/3))O_(3)-0.3PbTiO_(3)压电性能的机理研究  

Study on Mechanism of Alternating Current Poling Enhancing Piezoelectric Properties of Pb(Mg_(1/3)Nb_(2/3))O_(3)-0.3PbTiO_(3)

作　　者：王海旭 刘畅[1] 李翔宇 WANG Haixu;LIU Chang;LI Xiangyu(School of Mechanics and Aerospace,Southwest Jiaotong University,Chengdu 611756,China)

机构地区：[1]西南交通大学力学与航空航天学院,成都611756

出　　处：《四川轻化工大学学报（自然科学版）》2024年第5期1-8,共8页Journal of Sichuan University of Science & Engineering(Natural Science Edition)

基　　金：国家自然科学基金青年基金项目(P110622G04002)。

摘　　要：探讨了不同极化方式下Pb(Mg_(1/3)Nb_(2/3))O_(3)–0.3Pb Ti O_(3)(PMN-0.3PT)单晶的压电性能的变化。实验结果表明,相比于直流电极化,交流电极化后PMN-0.3PT单晶的压电系数d33从1421 pC/N提升至1857 pC/N,相对介电系数εr从4800提升至6650,压电系数与相对介电系数分别提升了30.7%和38.5%。为探究交流电优化机理,采用了实验和模拟相结合的方法,从极化畴结构演化的角度给出了解释。用压电力显微镜对PMN-0.3PT的畴结构进行了扫描,并利用相场模型对PMN-0.3PT的畴结构演化进行了表征,实验和模拟结果展现出相同的演化趋势;同时建立了相应的晶格演化模型进行解释。对于未极化的PMN-0.3PT单晶,畴结构呈现随机分布的状态;经过直流电极化后,电畴沿偏向电场的方向翻转,畴结构形貌呈现树枝状;在交流电极化后,PMN-0.3PT内部只存在两个不同极化方向,畴结构形貌呈现条带状。数值计算的结果表明,随着极化方式由无极化到直流极化再到交流极化,PMN-0.3PT的畴壁能从727.578变化到160.060再到57.910,伴随着畴壁能的减小,畴壁密度逐渐降低,这是导致压电性能提升的主要原因。该研究成果对深入理解弛豫铁电材料电畴结构与压电性能的内在联系及作用机理有非常重要的意义,并为优化铁电材料的压电性能给出了可行方案。The change of the piezoelectric properties of Pb(Mg_(1/3)Nb_(2/3))O_(3)-0.3PbTiO_(3)(PMN-0.3PT)single crystal under different polarization modes is investigated.The experimental results show that the piezoelectric coefficient(d33)of PMN-0.3PT single crystal increases from 1421 pC/N to 1857 pC/N after alternating current polarization compared with that is polarized by direct current,and the relative dielectric coefficient(εr)increases from 4800 to 6650,respectively,which is improved by 30.7%and 38.5%.To explore the optimization mechanism of alternating current polarization,the method combining experiment and simulation is adopted to explain the polarized domain structure evolution.The domain structure of PMN-0.3PT is scanned using the piezoelectric force microscope and characterized by phase field model.The experimental and simulation results show the same evolution trend;meanwhile,the corresponding lattice evolution model is established to explain the domain structure evolution.For the unpolarized PMN-0.3PT single crystal,the domain structure is randomly distributed.After the direct current polarization,the domain turns in the direction of the electric field,whose structure is dendritic.After alternating current polarization,only two polarization orientations exist in PMN-0.3PT,and the domain structure is banded.The numerical results show that the domain wall energy of PMN-0.3PT changes from 727.578 to 160.060 and then to 57.910 with the polarization mode changes from no polarization to direct current polarization and then to alternating current polarization.With the decrease of domain wall energy,the domain wall density gradually decreases,which is the main reason for the improvement of piezoelectric performance.The research results are highly significant in enhancing the understanding of the internal relationship and mechanism between the domain structure and piezoelectric properties of relaxed ferroelectric materials,and provide a feasible scheme for optimizing the piezoelectric properties of ferroelectric ma

关 键 词：PMN-0.3PT 压电性能调控 交流电极化 畴结构 相场模拟 

分 类 号：TB32[一般工业技术—材料科学与工程]