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铬掺杂对PZT-PMN陶瓷材料性能的影响 总被引:3,自引:0,他引:3
采用TEM、SEM、ESR(电子自旋共振)结合常规压电性能测试手段研究了Cr2O3掺杂对PZT-PMN陶瓷的压电性能、微结构及畴态的影响.压电性能测试结果表明,当Cr2O3含量低于0.06Wt%时,可使Kp和Qm同时提高,这说明铬掺杂同时兼具“软掺杂”与“硬掺杂”的双重特性.此外,还发现随着烧结温度的提高,材料性能“硬化”明显.ESR谱分析表明,Cr离子主要以Cr3+和 Cr5+的方式共存,随着烧结温度的提高,它有从高价态 Cr5+或Cr6+向低价态转变的趋势,这一价态变化被认为是材料性能随烧结温度提高而“变硬”的主要原因之一.TEM图片显示,随着掺杂的Cr2O3的浓度的增大,由于氧空位或受主离子与氧空位构成的缺陷复合体对畴壁的钉扎,电畴将从正规带状畴向波纹状畴转变. 相似文献
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高Tc铋层状压电陶瓷结构与性能 总被引:2,自引:0,他引:2
综述了铋层状压电陶瓷的结构特点及性能研究.铋层状压电陶瓷的结构由(Bi2O2)2+层和钙钛矿层(Am-1BmO3m+1)2-按一定规则共生排列而成.此处 A为适合干 12配位的离子;B为适合于八面体配位的离子,m为一整数,其值一般为1~5.与钛酸钡(BaTiO3)或锆钛酸铅(PZT)陶瓷相比,铋层状压电陶瓷具有以下特点:低介电常数、高Tc、机电耦合系数各向异性明显、低老化率、高电阻率等. 先前研究证明,居里温度不仅与极化原子位移、自发极化强度、A位Bi含量有关,而且还与取代离子的特性诸如离子半径、电负性、核外电子排布有关.压电活性低是铋层状陶瓷的本质缺点,通常发展该材料的途径为化学取代或晶粒取向技术.研究材料结构与性能之间的关系有助于发展铋层状压电陶瓷材料. 相似文献
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复合稀土掺杂α-Sialon的氧化行为 总被引:3,自引:0,他引:3
对组份为(Nd0.18Y0.18)Si10.38Al1.62O0.54N15.46和(Nd0.18Yb0.18)Si10.38Al1.62O0.54N15.46的复合稀土掺杂α-Sialon材料在1200~1400℃温度范围内的氧化行为进行了研究.样品由热压工艺制备.研究结果表明,在1200和1300℃氧化20h的材料表面存在择优取向的含Nd和Y(或Yb)-硅酸盐晶粒.随氧化温度的提高,氧化表面由相对致密的硅酸盐氧化层软化形成气泡直至出现明显的透明玻璃相.文中还对氧化过程中表面形成的物相进行了讨论. 相似文献
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利用高分辨率的Guinier-Hagg相机和计算机控制的底片扫描及数据处理程序系统,测定了复合添加,组份为(Ca0.5Mg0.5)xSi12-3xAl3xOxN16-x(x=0.3、0.6、1.0和1.4)的α-Soalon的晶胞参数.材料由热压工艺制备而得.研究结果表明,当x≥1.0时,材料的主晶相为α-Sialon和含Mg的AlN多型体.(Ca,Mg)-α-Sialon的晶胞参数明显低于相同组份下的Ca-α-Sialon的晶胞参数·EDAX的结果进一步给出固溶进入α-Sialon的包括名义组份中90%的Ca++和少量的Mg++,而大部分Mg++进入AlN多型体,这一结果为净化α-Sialon陶瓷的晶界提供了新的有效途径. 相似文献
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将位于同型相界附近的固溶体系9.91PZN-0.09PT作为一个组元,与同样位于准同上界的另一个组元Pb(Zr0.53Ti0.47)复合形成新的压电陶瓷体系(1-x)(0.91PZN-0.09PT)-xPb(Zr0.53Ti0.47)O3,实验结果表明新体第具有更好的压电,介电性能,对样品退火处理后,发现压电,介电性能有较大提高,Kp最高达到73%,d33最高达到570pc/N。 相似文献
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Jae Shin Lee Eun Chul Park Sang Hyun Lee Dae Su Lee You Jin Lee Jin Soo Kim Ill Won Kim Byung Moon Jin 《Materials Chemistry and Physics》2005,90(2-3):381-385
We have fabricated 0.2Pb(Mg1/3Nb2/3)O3–0.8Pb(Zr0.475Ti0.525)O3 [PMN–PZT] ceramics doped with various amounts of Li2O (0, 0.05, 0.1, 0.2, 0.3 wt.%) using the columbite precursor method. The effects of Li-doping on the conduction behavior of PMN–PZT ceramics are discussed in relation to the low frequency dielectric dispersion and frequency domain measurement. The Li-doped PMN–PZT ceramics sintered at 950 °C showed a sufficient densification with large dielectric constant and low dielectric loss. The incorporation of Li+ ion in PMN–PZT ceramics led to an appreciable reduction in electrical conductivity and further enhanced the ferroelectric and piezoelectric properties. The activation energies of PMN–PZT + xLi2O (x = 0, 0.05, 0.1, 0.2, 0.3 wt.%) ceramics calculated from ac conductivity measurement using the Arrhenius relation were 1.05, 1.25, 1.27, 1.38 and 1.41 eV, respectively. The conduction behavior is examined in the low frequency and high temperature region and the results are discussed in detail through crystal defect mechanism. 相似文献
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采用低频倒置扭摆内耗仪对组分为 Pb(Zr0.7Ti0.3)O3 (PZT73)和 Pb(Zr0.3Ti0.7)O3 (PZT37) 的两种陶瓷的内耗 Q-1及振动频率的平方 f 2(正比于材料的剪切模量 G)与温度的关系进行了 测定。在纯三角相的 PZT73陶瓷中发现两个内耗峰。高温内耗峰 PM起源于材料的顺电-铁 电相变 ,低温内耗峰 P1本质上是一个宽化的 Debye峰,可归因于氧空位作用下的畴壁振荡弛豫。 对纯四方相的 PZT37陶瓷,除了 P1和 PM峰外,在 P1与 PM峰之间另有内耗峰 P2,这与 900畴附 近的氧空位团簇的弛豫有关 ,其特征可用描述强关联系统的关联态模型( Coupling model)描述。 相似文献
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PZN-BZN和PZN-BT陶瓷介电性能研究 总被引:1,自引:1,他引:0
制备了Pb(Zn1/3Nb2/3)O3-Ba(Zn1/3Nb2/3)O3(PZN-BZN)和Pb(Zn1/3Nb2/3)O3-BaTiO3(PZN-BT)两类PZN基弛豫型铁电陶瓷,系统地研究了它们的介电性能以及热处理工艺对其介电性能的影响。合成出具有100%钙钛矿相的0.9PZN-0.1BZN陶瓷,其最大介电常数为6160(1kHz)。对比这两个系统的介电性能发现,PZN-BT系中隐含的BZN组分对陶瓷性能有着重要影响。退火热处理能显著提高PZN基陶瓷相变温度附近的介电常数,但对样品的相交扩散和介电弛豫现象没有明显影响。 相似文献
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Byun JM Lee HN Kwak JY Lee SE Lee HC 《Journal of nanoscience and nanotechnology》2012,12(4):3520-3523
This study investigated the morphological and electromechanical characteristics of 0.2PZN-0.8PZT films fabricated using a PbTiO3 layer. Crack-free 1-microm-thick films with a pure perovskite phase were obtained on Pt/Ti/SiO2/Si substrates using a modified sol-gel deposition method. A highly dense and smooth morphology and a high piezoelectric coefficient (d33) of 230 pC/N were observed in a 0.2PZN-0.8PZT film with a PbTiO3 insertion layer after annealing at 750 degrees C. The as-produced sol-gel-driven 0.2PZN-0.8PZT thin films are attractive for application to piezoelectrically operated microelectronic actuators, sensors, or energy harvesters due to their low facility cost, smooth surface, and excellent electromechanical characteristics. 相似文献
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Hosono Y Yamashita Y 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2005,52(10):1823-1828
Complex system ceramics Pb(Sc(1/2)Nb(1/2))O3-Pb(Mg(1/3)Nb(2/3))O3-Pb(Ni(1/2)Nb(1/2))O3-(Pb0.965,Sr0.035) (Zr,Ti)O3 (PSN-PMN-PNN-PSZT abbreviated PSMNZT) have been synthesized by the conventional technique, and dielectric and piezoelectric properties of the ceramics have been investigated for ultrasonic medical transducers. High capacitances of the transducers are desired in order to match the electrical impedance between the transducers and the coaxial cable in array probes. Although piezoelectric ceramics that have high dielectric constants (epsilon33t/epsilon0 > 5000, k'33 < 70%) are produced in many foundries, the dielectric constants are insufficient. However, we have reported that low molecular mass B-site ions in the lead-perovskite structures are important in realizing better dielectric and piezoelectric properties. We focused on the complex system ceramics PSMNZT that consists of light B-site elements. The maximum dielectric constant, epsilon33T/epsilon0 = 7, 200, was confirmed in the ceramics, where k'33 = 69%, d33 = 940 pC/N, and T(c) = 135 degrees C were obtained. Moreover, pulse-echo characteristics were simulated using the Mason model. The PSMNZT ceramic probe showed echo amplitude about 5.5 dB higher than that of the conventional PZT ceramic probe (PZT-5H type). In this paper, the electrical properties of the PSMNZT ceramics and the simulation results for pulse-echo characteristics of the phased-array probes are introduced. 相似文献
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锰掺杂对硬性PZT材料压电性能的影响 总被引:25,自引:0,他引:25
研究了锰掺杂对PZT材料微结构及压电性能的影响,并用ESR确定了锰在PZT材料中的价态.结果表明,锰在PZT材料中主要以 Mn2+和 Mn3+的方式共存.锰在PZT陶瓷材料中的“溶解度”约为1.5mol%.锰含量<0.5mol%时,Mn将以Mn2+和Mn3+的方式优先进入晶格 Pb位,使材料的压电性能提高,表现出施主杂质特性;锰浓度处于 0.5~1.5 mol%时,部分Mn将以Mn3+或Mn2+的方式进入晶格中(Zr;Ti)位,而此浓度范围内锰掺杂的PZT材料同时表现出“软性”和“硬性”材料的压电特性.锰含量>1.5mol%时,过量的Mn将在晶界积聚,使压电活性降低.少量Fe的存在,可使Mn离子的溶解度降低,并起到抑制Mn2+和 Mn3+氧化的作用. 相似文献
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Lead zirconate titanate, (Pb(Zr0.52Ti0.48)O3PZT) thin films were deposited onto a Pt/Ti/SiO2/Si substrate using radio frequency (r.f.) planar magnetron sputtering in this study. The deposited PZT thin films were almost amorphous before the annealing processes and developed a perovskite structure after the annealing process. If the annealing temperature was too low or annealing time too short, pyrochlore would form. However, if the annealing temperature was too high or annealing time too long, the thin film structure would degrade due to the volatilization of PbO. The significant finding in this experiment is that high quality perovskite PZT thin films on Pt/Ti/SiO2/Si substrates can be obtained by adjusting the annealing temperature to a range of 650 °C to 850 °C and annealing time to a range from 5 to 80 min. In this experiment, the optimal annealing condition was an annealing temperature of 650 °C and time of 20 min. The properties of PZT thin film annealed at 650 °C for 20 min were dielectric constant r = 869 free dielectric constant T
33 = 893 piezoelectric constant d33 = 2.03p m V-1 piezoelectric constant g33 = 2.57 x 10-4 V m N-1, remanent polarization P1 = 112.5 nC cm-2 and coercive field Ec= 0.061 kV cm-1. 相似文献