压电陶瓷PPT课件
压电陶瓷及其应用培训资料
超声波发生器
利用压电陶瓷的逆压电效应产生超声波，广泛应用于无损检测、医疗成像等领域 。
麦克风
利用压电陶瓷的压电效应，将声音转化为电信号，用于语音识别、录音等场合。
振动控制
振动隔离
通过控制压电陶瓷的形变，实现精密 仪器的振动隔离，提高测量精度。
振动主动控制
利用压电陶瓷的逆压电效应产生反作 用力，对结构振动进行主动控制，提 高结构的稳定性。
易于加工和集成
压电陶瓷可以通过微加工 技术进行加工和集成，实 现小型化和高精度。
压电陶瓷的发展历程
早期发展
20世纪初，科学家开始研 究压电陶瓷，并逐渐应用 于声呐、无线电等领域。
中期发展
随着科技的发展，压电陶 瓷在传感器、换能器等领 域的应用逐渐增多，性能 也不断提高。
近期发展
随着新材料和加工技术的 发展，压电陶瓷在微纳尺 度、智能传感器等领域的 应用越来越广泛。
电子听诊器
压电陶瓷在电子听诊器中作为传感器，将心跳或呼吸产生的 机械振动转换为电信号，用于医学诊断。
电子听诊器具有操作简便、准确度高、可重复性好等优点， 广泛应用于临床医学和家庭保健领域。
05
压电陶瓷的未来展望
新材料与新工艺的发展
新型压电陶瓷材料
随着科技的不断进步，新型压电陶瓷材料如纳米压电陶瓷、高温压电陶瓷等将不断涌现，为压电陶瓷 的应用提供更多可能性。
压电陶瓷及其应用培 训资料
目录
• 压电陶瓷简介 • 压电陶瓷的工作原理 • 压电陶瓷的应用领域 • 压电陶瓷的应用实例 • 压电陶瓷的未来展望
01
压电陶瓷简介
压电效应与压电陶瓷
压电效应
某些材料在受到外部压力时会产生电 场，这种现象称为压电效应。利用压 电效应制作的陶瓷称为压电陶瓷。
压电陶瓷ppt课件
感谢您的观看
THANKS
造传感器和换能器。
工作模式二
压电陶瓷可以在交变电场下工作， 产生交变的机械振动，用于制造超 声波设备和振动器。
工作模式三
压电陶瓷可以在高电压、大电流下 工作，产生强烈的机械振动或变形 ，用于制造大型驱动器和执行器。
03
压电陶瓷的制造工艺
配料与混合
配料
按照配方称取适量的原料，如钛 酸钡、二氧化锆、氧化镁等。
04
压电陶瓷的性能参数
电学性能
介电常数
衡量压电陶瓷在电场作用下极化 程度的物理量。介电常数越大， 极化程度越高，压电效应越明显
。
绝缘电阻
反映压电陶瓷内部绝缘性能的参 数。高绝缘电阻表明陶瓷内部缺
陷少，性能稳定。
电致伸缩系数
衡量压电陶瓷在电场作用下产生 的机械应变能力的物理量。电致 伸缩系数越大，机械应变能力越
压电陶瓷的特性
高压电性能
压电陶瓷具有较高的压电常数和机电耦合系 数，能够将微小的机械形变转换为较大的电 能或机械能。
温度稳定性
压电陶瓷具有较好的温度稳定性，可以在较 宽的温度范围内保持稳定的性能。
可靠性高
压电陶瓷具有较高的机械强度和稳定性，不 易疲劳压电陶瓷的振动和换能特性，可以将太阳能转换为电能，提高太阳能利用率 。
压电陶瓷在风能发电中的应用
压电陶瓷可以作为风能发电机的传感器和换能器，实现风能的高效利用。
压电陶瓷在其他领域的应用探索
压电陶瓷在医疗领域的应用
压电陶瓷在医学领域具有广泛的应用前景，如超声成像、药物传递等。
压电陶瓷在环保领域的应用
利用压电陶瓷的振动特性，制造出声 波发生器、超声波探头等声学器件。
压电陶瓷及其应用PPT课件
顺电相
铁电相
4. 铋层状结构
Bi4Ti3O12
（1） 钛酸钡压电陶瓷 钛酸钡（BaTiO3）是由碳酸钡（BaCO3）和二氧
化钛（TiO2）按1：1分子比例在高温下合成的压电陶瓷 。
它具有很高的介电常数和较大的压电系数（约为石 英晶体的50倍）。不足之处是居里温度低（120℃）， 温（度2）稳定锆性钛和酸机铅械系强压度电不陶如瓷石（英PZ晶T）体。
2019/12/23
22
铁路钢轨探头
铁路钢轨对接焊 缝探测用探头
缺陷 焊缝
2019/12/23
铁路钢轨探伤 用滑板式探头
23
管道环焊缝 超声波检测装置
2019/12/23
管道环焊缝超声 波检测装置原理
24
超声探伤仪
2019/12/23
25
构件的超声探伤
2019/12/23
26
构件的超声探伤
另外，PbTiO3陶瓷的介电系数小，热释电系 数大，接近于60μC/cm2·K，居里点高，抗辐射性 能好，还是一种相当理想的热释电探测器材料。
2. PbNb2O6 钨青铜结构 Tc高（570℃） 压电系数的各向异性大，d33/d31≈10 机械品质因素特别低（Q≈11）
主要用于超声缺陷检测、人体超身诊断及水听器等
4、压电半导体材料 如ZnO、CdS 、ZnO 、CdTe，这种力敏器件具有灵振荡器的压电材料，可测取力和温度等参数。
BaTiO3和PbTiO3压电陶瓷比较
BaTiO3陶瓷 工作温区窄（Tc=120℃
） 易极化 热稳定性差 ε=1900 Kp =0.354 d33=191(10-12库/牛) g33=11.4(10-3伏·米/牛) 工艺性好
压电陶瓷
The enhanced piezoelectric performance of Bi 1/2Na 1/2TiO 3–BaTiO 3ceramics by Ba 0.77Ca 0.23TiO 3substitutionLaihui Luo a ,⇑,Feng Ni a ,Huixin Zhang a ,Hongbing Chen ba Department of Physics,Ningbo University,Ningbo 315211,ChinabInstitute of Materials Science and Engineering,Ningbo University,Ningbo 315211,Chinaa r t i c l e i n f o Article history:Received 30December 2011Received in revised form 2May 2012Accepted 6May 2012Available online 12May 2012Keywords:Lead-free ceramic Piezoelectric Ferroelectric Depolarizationa b s t r a c tIn this study,lead-free (1Àx )Bi 0.47Na 0.47Ba 0.06TiO 3–x Ba 0.77Ca 0.23TiO 3(BNBT–x BCT,x =0–0.12)ceramics were fabricated by ordinary ceramic sintering technique.The results show that Ba 0.77Ca 0.23TiO 3(BCT)has diffused into Bi 0.47Na 0.47Ba 0.06TiO 3(BNBT)lattices to form a new solid solution BNBT–x BCT.Moderate substitution of BCT in BNBT–x BCT (x 60.01)ceramics can enhance the piezoelectric and ferroelectric properties;meanwhile,depolarization temperature of the ceramics does not decrease.BNBT–0.01BCT ceramic exhibits the best piezoelectric properties and strongest ferroelectricity:piezoelectric coefficient d 33=178pC/N;electromechanical coupling factors k t =50%and k p =27%;quality factor Q m =131;rem-nant polarization P r =36l C/cm 2;coercive field E c =24.5kV/cm.The piezoelectric properties,ferroelectric characteristics and depolarization mechanism of the ceramics are investigated and discussed.Published by Elsevier B.V.1.IntroductionLead-based piezoelectric ceramics based on Pb(Zr,Ti)O 3(PZT)are widely used in piezoelectric devices because of their excellent electrical properties near morphotropic phase boundary (MPB)[1].However,the use of lead-based piezoelectric ceramics has caused serious lead pollution due to the high toxicity of lead oxide and its high volatility during sintering.Therefore,much attention has been paid to the search for lead-free piezoelectric ceramics with high piezoelectric properties.Bi 1/2Na 1/2TiO 3(BNT)is considered to be an excellent candidate for lead-free piezoelectric ceramics due to its large remnant polar-ization (P r =38l C/cm 2)at room temperature.However,the piezo-electric performance of the pure BNT is relatively low,and it requires a large driving field during practical application due to its high coercive field (E c =73kV/cm)[2].In order to improve the piezoelectric performance and reduce the driving field of BNT cera-mic,a number of BNT-based solid solutions have been developed,such as BNT–BaTiO 3(BNT–BT)[3,4],BNT–Bi 1/2K 1/2TiO 3[5,6],BNT–KNbO 3[7],BNT–BT–Bi 1/2Li 1/2TiO 3[8],BNT–Ba(Ti,Zr)O 3[9],BNT–BT–KNbO 3[10,11],and BNT–Bi 1/2K 1/2TiO 3–Bi 1/2Li 1/2TiO 3[12].It has been reported that the multi-component piezoelectric ceramics possess better piezoelectric performances than single or binary-component ceramics due to the more complex phase structure in multi-component lead-base piezoelectric ceramics.From the liter-ature mentioned as above,it can also be found that the ternary sys-tems have superior piezoelectric response to the single or binary systems in BNT-based ceramics.Many compounds have been added to BNT–BT to improve its piezoelectric response.However,it seems to be a contradiction between the piezoelectric performances and depolarization tem-perature in BNT-based ceramics.The depolarization temperature reduces sharply with the substitution.It even decreases to ambient temperature,such as BNT–BT–Ag 0.9Li 0.1NbO 3[13],BNT–BT–Bi 1/2Ag 1/2TiO 3[14],BNT–BT–La 1/2Na 1/2TiO 3[15]BNT–BT–K 1/2Na 1/2NbO 3[16,17].Therefore,it is necessary to search a substi-tution to improve the piezoelectric response of BNT–BT ceramics;meanwhile,the depolarization temperature of the ceramics doesn’t reduce.(1Àx )BNT–x BT ceramics with x =0.06–0.07have a large pie-zoelectric response [2,18,19],and 0.94BNT–0.06BT (Bi 0.47Na 0.47Ba 0.06TiO 3)is the optimized composition for a large piezoelectric re-sponse in (1Àx )BNT–x BT solid solution [3,18].Therefore,Bi 0.47Na 0.47Ba 0.06TiO 3(BNBT)is chosen as a basic chemical formula in this work.On the other hand,Ba 0.77Ca 0.23TiO 3(BCT)is tetragonal phase at room temperature.It is also a promising candidate of lead-free piezoelectric material due to its large electrostriction and piezo-electric response [20].BCT combined with Ba(Ti 0.8Zr 0.2)O 3is used to synthesize solid solution Ba(Ti 0.8Zr 0.2)O 3–BCT,and its piezoelec-tric coefficient d 33reaches a ultrahigh value of $620pC/N [21].In this study,the mole ratio of BNT/BT is set as 0.94/0.06,and BCT is chosen as the third component to modify the electrical prop-erties of BNT–BT–Ba 0.77Ca 0.23TiO 3.The chemical formula of ternary system ceramics is written as (1Àx )Bi 0.47Na 0.47Ba 0.06TiO 3–x Ba 0.77-Ca 0.23TiO 3(BNBT–x BCT,x =0–0.12).In the current work,BNBT–x BCT ceramics are prepared by a conventional ceramic technique.0925-8388/$-see front matter Published by Elsevier B.V./10.1016/j.jallcom.2012.05.017Corresponding author.Tel.:+8657487600953;fax:+8657487600744.E-mail address:llhsic@ (L.Luo).The microstructure,ferroelectricity,piezoelectric properties and depolarization mechanism of the ternary system ceramics were investigated and discussed.2.ExperimentalBNBT–x BCT(x=0,0.005,0.01,0.02,0.04,0.06,0.12)prepared by a conventional ceramic fabrication technique.ders:Bi2O3(99.9%),Na2CO3(99.8%),BaCO3(99%),TiOused as starting raw materials.The powders in the stoichiometricin alcohol with agate balls for10h,and then dried andThe calcined powders were reground by ball milling forders were sieved and mixed thoroughly with a PVA binderially pressed into disk samples with a pressure of$100then sintered at1100–1200°C for2h in air to form theSilver paste was pasted on both sides of the disc samplesorder to form electrodes.All specimens were poled underat80°C in silicone oil bath for30min,and then cooledthe polingfield.The crystal structure of the ceramicsfraction(XRD)analyzer(Bruker D8Advance)with Cutric coefficient d33of the samples was measuredmeter(ZJ-3AN,China).Dielectric constant e33and dielectricsamples as a function of temperature at10kHz,100kHzusing a computer-controlled impedance analyzer(Agilent4294A).The polarization vs.electricfield(P–E)hysteresis loop was obtained at1Hz with the RT Premier II ferroelectric workstation.The mechanical quality factor Q m and electromechanical coupling factors k p,k t were calculated using the resonance-antiresonance method with the impedance analyzer(Agilent4294A)according to the IEEE standard on piezoelectricity measurement.Fig.1.XRD patterns of BNBT–x BCT ceramics.Fig.2.P–E hysteresis loops of BNBT–x BCT:(a)x=0.00;(b)x=0.005;(c)x=0.01;(d)x=0.02;(e)x=0.04;(f)x=0.12.3.P r and E c as a function of the BCT content x for the BNBT–x BCT ceramics.3.Results and discussionsX-ray diffraction patterns are shown in Fig.1(a).Thefigure indi-cates that all the BNBT–x BCT ceramics have a pure perovskite structure and no detectable second phase is found,meaning that BCT has diffused into BNBT lattices to form a new solid solution BNBT–x BCT.Many reports in the literature assume the BNT as a rhombohedral phase following the investigation of Jones and Tho-mas[7,22].It is also reported that the symmetry of BNT should be monoclinic phase[23,24].When we come to BNT’s solid solution with BT,the symmetry of the solid solution becomes more com-plex.It is well known that the structure of these solid solutions is nothing but a cubic one at least within the resolution limit of dif-fraction techniques[25–28].A sufficient amount of electricfield can induce the cubic–tetragonal phase transition[29,30].The phase of BNBT can be seen as pseudocubic phase within the sensitivity of XRD at room temperature,meanwhile,BCT is tetrag-onal.It is reasonable to infer that the structure of BNBT–x BCT will transform from pseudocubic phase to tetragonal phase with the increment of BCT content.Fig.1(b)is the XRD patterns in Fig.1(a)with the2h angle ranging from43°to51°.Only one (200)pc peak is observed in the diffraction patterns when the BCT content x is0.00,0.005,and0.01,implying that BNBT–0.00BCT,BNBT–0.005BCT and BNBT–0.01BCT are pseudocubic phase.With the increment of BCT,(200)pc peak splits to(200) and(002)peaks,suggesting that the ceramics transform from pseudocubic phase to tetragonal phase when x P0.02.Fig.2shows the P–E hysteresis loops of BNBT–x BCT ceramics 30°C.It is found that well saturated and square-like loops obtained for ceramics BNBT–0.00BCT,BNBT–0.005BCT and0.01BCT.As shown in Fig.2(a),the remnant polarization coercivefield E c of BNBT–0.00BCT ceramic reach30.5l C/cm28kV/cm,respectively.Remnant polarization P r=36l C/cm coercivefield E c=24.5kV/cm are obtained for BNBT–0.01BCT.Fig.4(a)presents the piezoelectric coefficient d33and electro-mechanical coupling factor k t of BNBT–x BCT ceramics as a function of BCT content x.d33and k t increase sharply as x increases,and then decrease when x P0.02due to the appearance of tetragonal phase.As Fig.4(a)shows,BNBT–0.01BCT ceramic owns a high pie-zoelectric response:d33=178pC/N,k t=50%.The significant enhancement in piezoelectricity of the BNBT–0.01BCT ceramics should be attributed to the appearance of more complex phase structure in the as-prepared ceramics.Fig.4(b)shows the dielectric constant e33and dielectric loss tan d measured at1kHz for BNBT–x BCT ceramics.It can be observed that the behaviors of e33and tan d as a function of BCT content x are analogous to each other, and the maximum values(e33=1121and tan d=0.0330)are obtained at x=0.02and0.06,respectively.Fig.5presents the mechanical quality factor Q m and the planar electromechanical coupling factor k p of BNBT–x BCT ceramics.Both the mechanical quality factor Q m and planar electromechanical coupling factor k p of the ceramics decrease with BCT content.Q m and k p of BNBT–0.01BCT ceramic reach131and27%,respectively.Fig.6shows the temperature dependences of dielectric con-stant e33and dielectric loss tan d for the poled BNBT–x BCT ceramics with x=0,0.01,0.02,0.04,0.06and0.12at10,100and1MHz.As marked in Fig.6(a)-(f),two dielectric anomalies can be observed at T d and T m.T d is corresponding to the depolarization temperature, which can be obtained from the temperature at which thefirst peak of dielectric loss tan d is obtained.When BNBT–x BCT ceramics are heated to the temperature above T d,the piezoelectric response of the samples disappears.Fig.6shows that e33and tan d are dependent on the test frequency near T d.However,T d isPiezoelectric coefficient d33and electromechanical coupling factor k t of BNBT–x BCT ceramics as a function of BCT content x.(b)Dielectric constant e33and of BNBT–x BCT ceramics measured at1kHz.5.Planar electromechanical coupling factor k p and mechanical quality factorof BNBT–x BCT ceramics as a function of BCT content x.independent on the test frequency.T m is corresponding to perature,at which a maximum e 33at 10kHz is obtained.ceramics exhibit a relatively broad dielectric peaks near BNBT–0.00BCT ceramic,a sharp increment of the e 33and tan 107°C is observed,which is attributed to the occurring of ization.At temperature higher than T d ,dielectric constant creases gradually with temperature and reaches the maximum value at temperature T m =270°C.In addition,after a sharp ment of e 33with temperature,an obvious relaxor-like can be observed above T d (Fig.6(a)).As the increment of BCT tent,the phase transition near T d becomes less steep.T d and function of BCT content x is shown in Fig.7.With moderate tution of BCT,both T d and T m of BNBT–x BCT vary a little x .Depolarization temperature T d is critical for piezoelectric vices;a high T d is very significant for the temperature stability piezoelectric devices.T d of BNBT–0.01BCT is 108°C;meanwhile,Temperature dependences of e 33and tan d for the BNBT–x BCT ceramics at 10kHz,100kHz and 1MHz:(a)x =0.00;(b)x =0.01;(c)x =0.02;(d)x =0.04;(e)Fig.7.T d and T m as function of BCT content x .T d of BNBT–0.00BCT is107°C.However,the piezoelectric response of BNBT–0.01BCT is much larger than that of BNBT–0.00BCT.It is highly significant to improve the piezoelectric response without the decrement of the depolarization temperature.The depolariza-tion temperature T d observed here is much higher than the values obtained in BNT–BT–Ag0.9Li0.1NbO3[13],BNT–BT–Bi1/2Ag1/2TiO3and BNT–BT–La1/2Na1/2TiO3[15].In the present study,T d increases sharply with x when x P0.02,and T d of BNBT–0.12BCT reaches164°C.The improvement of T d is related to the develop-temperature,which is consistent with the steep variation of e33 and tan d with temperature near T d,as shown in Fig.6(a).For BNBT–0.06BCT,k p increases little as temperature increases to 120°C.At above120°C,it begins to reduce with temperature.As shown in Fig.8,k p of BNBT–0.06BCT is nearly independent on tem-perature at below120°C.The slope of k p vs.temperature during depolarization for BNBT–0.06BCT is not as steep as that of BNBT–0.00BCT.The results are consistent with the dielectric constant vs.temperature measurement,as shown in Fig.6.The piezoelectric response in ferroelectrics has been attributed to:(1)intrinsic pie-zoelectric response of the ferroelectric lattice;(2)domain move-ment[31,32]:domain moves more easily at higher temperature due to the softening of the Young’s modulus;(3)the phase transi-tion between rhombohedral phase and tetragonal phase,and it is easier to occur at higher temperature near MPB[21,33],which brings a high piezoelectric response.Due to being far away from MPB,there is no contribution to the piezoelectric response from the phase transition between rhombohedral phase and tetragonal phase for BNBT–0.06BCT.In a word,the piezoelectric performances of BNBT–0.06BCT might be mainly from the intrinsic contribution of lattice.However,the phase transition may contribute to the pie-zoelectric response of BNBT–0.00BCT and BNBT–0.01BCT ceramics due to their large dependence of k p on temperature.The P–E hysteresis loops of the BNBT–x BCT ceramics with x=0, 0.01and0.06at different temperature are presented in Fig.9.Allk p as a function of temperature for the BNBT–x BCT ceramics with xand0.06.Fig.9.P–E hysteresis loops of the BNBT–x BCT ceramics at different temperature:(a)x=0.00;(b)x=0.01;(c)x=0.06.Compounds536(2012)113–1181170.01BCT and BNBT–0.06BCT exhibit similar temperature depen-dence of the ferroelectric properties,being similar to the ceramic BNBT–0.00BCT.What occurs near T d?The researchers have different opinions on the depolarization mechanism near T d.Some researchers consider that phase transition from a ferroelectric phase to an antiferroelec-tric phase occurs near T d in BNT-based lead-free piezoelectric ceramics due to the appearance of a constricted hysteresis loop near T d[2,34,35],and a large strain induced by the antiferroelectric-fer-roelectric transition[34,35].However,experiments such as X-ray diffraction,Raman and neutron scattering do not support the exis-tence of anti-ferroelectric phase above T d in BNT-based ceramic [36,37].The appearance of the constricted hysteresis loop is consid-ered as a concrete proof of ferroelectric-antiferroelectric transition. However,constricted hysteresis loop is common in relaxor ferro-electrics even in normal ferroelectrics[38,39].Some researchers consider that macro–micro domain transition occurs near T d in BNT-based ferroelectrics[3,7,40].Some researchers roughly pro-pose that it is polar-nonpolar region transition at T d in BNT-based ceramics[11,13–15].Recently,some scientists[41,42]alleged that long-range ferroelectric phase and ergodic relaxor phase coexist nearly throughout the entire temperature range and reversibly transform into each other with temperature in the relaxor BNT-based ceramics.Sapper et al.think that depolarization during heat-ing occurs before long-range ferroelectric order breaks[43].4.ConclusionIn conclusion,we have successfully prepared lead-free piezo-electric BNBT–x BCT ceramics by a conventional ceramic technique. BNBT–0.01BCT ceramic exhibits excellent piezoelectric properties and strong ferroelectricity:piezoelectric coefficient d33=178pC/ N;electromechanical coupling factors k t=50%and k p=27%;quality factor Q m=131;remnant polarization P r=36l C/cm2;coercivefield E c=24.5kV/cm.Piezoelectric properties and ferroelectricity of BNBT–0.01BCT ceramic are much better than those of BNBT due to its more complex phase structure.The piezoelectric response of BNBT-0.01BCT ceramics increases with temperature before depolarization.Furthermore,depolarization temperature T d of BNBT–0.01BCT ceramic is as high as that of BNBT,achieving 108°C.The P–E loops of the prepared ceramics at different temper-ature are investigated;however,the exact depolarization mechanism is not obtained.The depolarization mechanism of BNT-based ceramics is still open.AcknowledgmentsThis work was supported by the National Natural Science Foun-dation of China(51002082,11004113),Natural Science Foundation of Zhejiang Province(Y4090057),Natural Science Foundation of Ningbo(2009A610016,201201A6105044),the Outstanding(Post-graduate)Dissertation Growth Fundation of Ningbo University (PY20110011)and the K.C.Wong Magna Foundation in Ningbo University(XYL10012,xkz11203).References[1]Y.Saito,H.Takao,T.Tani,T.Nonoyama,K.Takatori,T.Homma,T.Nagaya,M.Nakamura,Nature432(2004)84–87.[2]T.Takenaka,K.Maruyama,K.Sakata,Jpn.J.Appl.Phys.30(1991)2236.[3]B.Chu,D.Chen,G.Li,Q.Yin,J.Eur.Ceram.Soc.22(2002)2115.[4]X.Zhou,H.Gu,Y.Wang,W.Li,T.Zhou,Mater.Lett.59(2005)1649.[5]I.Makoto,Y.Katsuya,S.Muneyasu,N.Yuji,M.Masaru,Appl.Phys.Lett.93(2008)903.[6]A.Sasaki,T.Chiba,Y.Mamiya,E.Otsuki,Jpn.J.Appl.Phys.38(1999)5564.[7]G.Fan,W.Lu,X.Wang,F.Liang,J.Xiao,J.Phys.D:Appl.Phys.41(2008)035403.[8]D.Lin,D.Xiao,J.Zhu,P.Yu,J.Eur.Ceram.Soc.26(2006)3247.[9]H.Ishii,H.Nagata,T.Takenaka,Jpn.J.Appl.Phys.40(2001)5560.[10]H.Ni,L.H.Luo,W.P.Li,Y.J.Zhu,H.S.Luo,J.Alloys Compd.509(2011)3958–3962.[11]J.M.Li,F.F.Wang,X.M.Qin,M.Xu,W.Z.Shi,Appl.Phys.A-Mater.10.1007/s00339-010-6074-5.[12]D.Lin,Q.Zhen,C.Xu,K.W.Kwok,Appl.Phys.A-Mater.93(2008)549–558.[13]L.Wu,N.Liu,F.Zhou,W.Wu,Y.Teng,Y.Li,J.Alloys Compd.507(2010)479–483.[14]L.Wu,D.Xiao,F.Zhou,Y.Teng,Y.Li,J.Alloys Compd.509(2011)466–470.[15]Q.Zheng,C.Xu,D.Lin,D.Gao,K.W.Kwok,J.Phys.D:Appl.Phys.41(2008)125411.[16]S.Zhang,A.B.Kounga,E.Aulbach,H.Ehrenberg,J.Rödel,Appl.Phys.Lett.91(2007)112906.[17]S.Zhang,A.B.Kounga,E.Aulbach,T.Granzow,W.Jo,H.Kleebe,J.Rödel,J.Appl.Phys.103(2008)034107.[18]G.Xu,Z.Duan,X.Wang,D.Yang,J.Cryst.Growth275(2005)113.[19]A.Herabut,A.Safari,J.Am.Ceram.Soc.80(1997)2954.[20]X.Wang,H.Yamada,C.Xu,Appl.Phys.Lett.86(2005)022905.[21]W.Liu,X.B.Ren,Phys.Rev.Lett.103(2009)257602.[22]G.O.Jones,P.A.Thomas,Acta.Cryst.B58(2002)168.[23]S.Gorfman,P.A.Thomas,J.Appl.Cryst.43(2010)1409.[24]E.Aksel,J.S.Forrester,J.L.Jones,et al.,Appl.Phys.Lett.98(2011)152901.[25]R.Ranjan,A.Dviwedi,Solid State Commun.135(2005)394.[26]W.Jo,J.E.Daniels,J.L.Jones,et al.,J.Appl.Phys.109(2011)014110.[27]K.T.P.Seifert,W.Jo,J.Rödel,J.Am.Ceram.Soc.93(2010)1392.[28]J.E.Daniels,W.Jo,J.Rödel,et al.,Acta Mater.58(2010)2103.[29]W.Jo,J.Rödel,et al.,Appl.Phys.Lett.99(2011)042901.[30]J.E.Daniels,W.Jo,J.Rödel,J.L.Jones,Appl.Phys.Lett.95(2009)032904.[31]Q.Zhang,H.Wang,N.Kim,L.E.Cross,J.Appl.Phys.75(1994)454–459.[32]S.-E.Park,T.-R.Shrout,J.Appl.Phys.82(1997)1804.[33]D.Viehland,J.Li,A.Amin,J.Appl.Phys.92(2002)3985.[34]Y.Guo,M.Gu,H.Luo,Y.Liu,R.L.Withers,Phys.Rev.B83(2011)054118.[35]Y.Guo,Y.Liu,R.L.Withers,F.Brink,H.a Chen,Chem.Mater.23(2011)219–228.[36]J.A.Zvirgzds,P.P.Kapostins,J.V.Zvirgde,T.V.Kruzina,Ferroelectrics40(1982)75–77.[37]M.S.Zhang,J.F.Scott,Ferroelectr.Lett.6(1986)147–152.[38]X.Ren,Nat.Mater.3(2004)91–94.[39]Z.Feng,X.Ren,Phys.Rev.B77(2008)134115.[40]Q.Zhang,X.Zhao,R.Sun,H.Luo,Phys.Status Solidi A208(2011)1012–1020.[41]W.Jo,S.Suhaab,E.Sapper,L.Schumitt,H.J.Kleebe,A.Bell,J.Rödel,J.Appl.Phys.110(2011)074106.[42]V.V.Shvartsman,D.C.Lupascu,J.Am.Ceram.Soc.95(2012)1–26.[43]E.Sapper,S.Schaab,W.Jo,T.Granzow,J.Rödel,J.Appl.Phys.111(2012)014105.118L.Luo et al./Journal of Alloys and Compounds536(2012)113–118。
压电陶瓷ppt课件
三、压电陶瓷的应用
1880~1940：压电晶体； 上世纪40年代中期：BaTiO3压电陶瓷问世； 由于压电陶瓷具有突出优点，包括： 制造方便，设备简单，成本低廉，不受尺寸大小限制，可
其它几种重要的压电陶瓷包括
PbTiO3- PbZrO3；
Pb(Mg1/3Nb2/3)O3- PbTiO3- PbZrO3 ；
Pb(Co1/3Nb2/3)O3- PbTiO3- PbZrO3 ；
Na0.5K0.5NbO3 ；Pb0.6Ba0.4Nb2O6 ；
BNT(B0.5Na0.5TO3)、KNN(K0.5Na0.5NbO3）等。
3
表征参数
机电偶合系数K
or：
K2
由压电效应转换的电能 储入的机械能总量
K
2
由逆压电效应转换的机械能 储入的电能总量
K值越大，材料的压电耦合效应越强。 除此之外，还有压电系数d、机械品质因素Q、
弹性系数S和频率常数N等。
4
主晶相结构
钙钛矿型、钨青铜型、焦绿石型、含钛层状结构。
目前应用最广泛的是BaTiO3、PbTiO3、 PbZrO3等, 都属钙钛矿型晶胞结构。
第二相变点
92 % mol 8% mol
0.2 % wt 120℃ -45℃
88 % mol 4 % mol 8 % mol
160℃ -50℃
7
锆钛酸铅（PbTiO3—PbZrO3，缩写PZT）陶瓷: Tc>300℃, 在 -50℃ ～ 300℃ 范 围 内 无 相 变 点 ， 压 电 常 数 比 BaTiO3大二倍多，因此，它是目前品种最多，产量最大，应 用最为广泛的压电陶瓷。
1. 压电效应
常用压电陶瓷发射换能器课件
压电陶瓷发射换能器的优缺点
温度稳定性差
压电陶瓷的性能受温度影响较大，温度变化会影响其工作性 能。
成本较高
由于制造工艺和材料成本较高，导致压电陶瓷发射换能器的 成本较高。
02
压电陶瓷发射换能器的结 构与材料
压电陶瓷材料
压电陶瓷材料是具有压电效应的 陶瓷材料，能够在外部电场的作 用下产生形变，或者在内部应变
能器的频率响应范围。
带宽越宽，换能器的频率响应范 围越广，能够产生不同频率的声
波或振动。
带宽的测量单位是赫兹（Hz）， 不同用途的换能器有不同的带宽
要求。
效率与损耗
01
效率是压电陶瓷发射换 能器的能量转换效率， 它决定了换能器的性能 和效果。
02
效率越高，换能器的能 量转换效率越高，能够 产生更好的声波或振动 效果。
02
在制造过程中，需要控制材料的 成分和工艺参数，以保证换能器 的性能和稳定性。
03
压电陶瓷发射换能器的性 能参数
输出功率
输出功率是压电陶瓷发射换能 器的重要性能参数之一，它决 定了换能器的能量转换效率和 使用效果。
输出功率越高，换能器的能量 转换效率越高，能够产生更大 的声波或振动。
输出功率的测量单位是瓦特（ W），不同用途的换能器有不 同的输出功率要求。
工作原理
当压电陶瓷受到外部电场作用时，会产生形变，这种形变与电场方向相反，大 小成比例。通过施加交变电场，可以产生交变的形变，从而产生声波或超声波 。
压电陶瓷发射换能器的应用领域
医学成像
用于超声成像设备，如 超声诊断仪、超声治疗
仪等。
无损检测
用于检测材料内部结构 、缺陷等的无损检测设
备。
声学研究
材料物理 压电陶瓷.ppt
l1越小，fs越大
2019/10/25
27
逆压电效应使压电材料产生形变，形变又会产生
电信号，如果压电元件上加上交流信号，当交流电信
号的频率与元件（振子）的固有振动频率fT相等时， 便产生谐振。振动时晶格形变产生内摩擦，而损耗一
11
z
o
x
y
x
z z
b
o
o
y
x
cy
a
(a)
(b)
(c)
(a) 晶体外形； (b) 切割方向； (c) 晶片
2019/10/25
12
石英晶体
石英（SiO2）是一种具有良好压电特性的压电晶体。 其介电常数和压电系数的温度稳定性相当好，在常温范 围内这两个参数几乎不随温度变化，如下两图。
由图可见，在20℃～200℃范围内，温度每升高1℃， 压电系数仅减少0.016％。但是当到573℃时，它完全失 去了压电特性，这就是它的居里点。
2019/10/25
25
机械品质因素Qm
谐 振 时 振 子 储 存 的 机 械能
Qm 2 每 一 谐 振 周 期 振 子 所 消耗 的 机 械 能
表示在振动转换时，材料内部能量损耗的程度； Qm全面越高，能量损耗就越小； 产生的原因是存在内摩擦。
2019/10/25
26
频率常数N
对特定的陶瓷材料，其压电振子的谐振频率 和振子方向长度的乘积是一常数，称为频率常 数。由材料的性质决定,而与尺寸因素无关。
• 陶瓷压电材料 优点：抗酸碱，机电耦合系数高，易制程任意形状。 缺点：温度系数大，需高压极化处理(kV/mm)。
• 高分子压电材料 优点：低声学阻抗特性，柔软可做极薄的组件。 缺点：压电参数小，需极高的极化电场(MV/mm)
压电陶瓷幻灯片课件
效应称为逆压电效应。
-
+
+
+
-
+ -
压电效应的本质：机械作用引起 介质极化
晶体中离子电荷的位移，当不
F －－－－－ － ＋＋＋＋＋
存在应变时电荷在晶格位置上分
极化方向
布是对称的，所以其内部电场为
－－－－－ ＋＋＋＋＋＋
零。但当给晶体施加应力则电荷 发生位移，如果电荷分布不在保（实线正代压表电形效变应前示的意情图况，虚线 持对称就会出现净极化，并将伴 代表形变后的情况）
酒石酸钾纳（在常温下有压电性，技术上有使用价值，但有易溶 解的缺点 ）；
磷酸铵低于-14 8℃下才有压电性，工程使用价值不大。
（2）.聚合物 PVF2（聚二氟乙烯）
（3）.压电陶瓷
并非所有的陶瓷都具有压电效应。作为压电陶瓷的原材料，在晶 体结构上一定是不具有对称中心的晶体，如氧化铅、氧化锆、氧 化钛、碳酸钡、氧化铌、氧化镁、氧化锌等。
Pizoelectric Ceramics
压电陶瓷
ቤተ መጻሕፍቲ ባይዱ
钛酸铋钠及应用
Bi0.5Na0.5TiO3 钙钛矿型晶体，有
希望取代铅基压电材料
<001>
<111>
<110>
Perovskite Structure
日本共同社报道，JR东日本公司将从10日开 始在东京站八重洲北口第三次进行“发电地 板”试验。本次试验的目标是实现一人通过 时产生令100瓦的灯泡发光0.1秒的电力，并 希望在不久的将来实现用“发电地板”维持 自动检票机在处理IC卡时所需的电力。
变化较大。 1P压9b电5T4i性O年能3美(P国ZTB)·固贾溶菲体等系人统，。发优现点了：压非电常Pb强Z与rO稳3 定- 的 在1970年后，添加不同添加剂的二元系PZT陶瓷具
- 1、下载文档前请自行甄别文档内容的完整性，平台不提供额外的编辑、内容补充、找答案等附加服务。
- 2、"仅部分预览"的文档,不可在线预览部分如存在完整性等问题,可反馈申请退款(可完整预览的文档不适用该条件!)。
- 3、如文档侵犯您的权益，请联系客服反馈,我们会尽快为您处理(人工客服工作时间：9:00-18:30)。
ij 12
22
2
3
13 23 33
20
压电陶瓷的介电常数
单斜晶系：4个独立的非零分量： 11， 22， 33， 31 斜方晶系：11、 22、 33 三个独立非零分量 四方、六方、三方晶系：11 33 2个独立非零分量 11= 22, 3ห้องสมุดไป่ตู้为非零分量，而12 = 23 = 31 = 0 立方晶系：11 一个独立非零分量
S u b g ro u p F e rro e le c tric S p o n ta n e o u s ly p o la riz e d P o la riz a tio n re v e rs ib le
11
压电陶瓷
只有20个点群的晶体具有压电性 Category:
Dielectrics > Piezoelectrics > Pyroelectrics > Ferroelectrics 铁电陶瓷经极化处理后，才呈现压电效应。
12
正压电效应
电荷与应力成比例，用介质 电位移D和应力X表达如下：
DdX
式中D的单位为C/m2，X的 单位为N/m2，d称为压电常 数(C/N)。
13
逆压电效应
其应变x与电场强度E(V/m)
的关系
xdE
对于正、逆压电效应，比例 常数d在数值上相等
dD /Xx/E
14
弹性常数
具有一定形状、大小和被覆工作电极的压电陶瓷称为 压电陶瓷振子。实际振子谐振时的变形可视为弹性变 形。弹性常数是反映材料在弹性形变范围内应力与应 变关系的物理量。
D2 = 21 E1 + 22 E2 + 23 E3
D3 = 31 E1 + 32 E2 + 33 E3
17
压电陶瓷的介电常数
晶体的宏观物理性质都是用张量描述，受两种完全不同的对称性 的影响：
热力学关系（守恒定律）赋予物理性质本身的固有对称性对宏观 物理性质的影响－－要求描述晶体宏观物理性质的二阶以上张量 都是对称张量，如
极化的压电陶瓷的对称性为 ∞mm，类似于 6mm对 称性，非零独立压电常数的数量减少，压电常数只有 d31 = d32, d33, d15 = d24 其压电常数矩阵是：
0 0 0 0 d15 0
0
0
0 d24 0 0
d31 d32 d33 0 0 0
24
压电常数
压电应变常数 d
di
XDi
弹性常数服从胡克定律：在弹性限度范围内，应力与 应变成正比。即
x= sX X = cx s—弹性顺度常数m2/N c—弹性劲度常数N/m2
15
压电陶瓷的弹性常数
应力和应变张量都是二阶对称张量, Xij， xij 可以采用简化下标的形式表示
111，22 2，33 3，23 4，31 5，12 6 广义虎克定律：
21 Noncentrosymmetric
11 Centrosymmetric (non-piezoelectric)
20 P ie z o e le c tric P o la riz e d u n d e r s tre s s
10 P y ro e le c tric S p o n ta n e o u s ly p o la riz e d
电位移（或极化强度）等电学量之间的耦合效应。
9
压电性取决于晶体的对称性，压电性对晶体对称性 的要求－－无对称中心
10
Interrelationship of piezoelectric and subgroups on the basis of symmetry
32 S y m m e try Point Groups
3
压电陶瓷的基本物理性能
4
何谓压电陶瓷？
压电陶瓷：具有压电效应的功能陶瓷。
正压电效应：在没有对称中心的晶体上施加压力、张力、切向 力时，则发生与应力成比例的介质极化，且在晶体两端出现正、 负电荷；
逆压电效应：在晶体上施加电场引起极化时，产生与电场强度 成比例的变形或机械应力。
5
压电陶瓷的性能
21
压电常数
压电常数是反映力学量（应力或应变）与电学量（电 位移或电场）间相互耦合的线性响应系数。
22
压电陶瓷的压电常数
正压电效应：Di = dijk Xjk dijk 压电常数，18个分量 逆压电效应：xjk = djki Ei
用热力学可以证明逆压电常数与正压电常数相等
23
压电陶瓷的压电常数
压电效应 弹性常数（s，c）
介电常数（）
压电常数（d ） 压电方程 机电耦合系数(K) 机械品质因数（Qm） 稳定性 谐振频率（fr） 压电性/介电性/弹性/铁电性
6
压电效应
正压电效应
D=dX
逆压电效应
x=dE
7
正逆压电效应
8
压电效应 晶体的压电效应是应力和应变等机械量与电场强度和
E
xEi
X
--单位应力产生的电位移/单位电场引起的应变
压电电压常数 g－单位应力引起的电压
gi
XEi
D
D xi X
压电应力常数 e－单位电场引起的应力
ei D xi E XEi x
压电劲度常数 h－造成单位应变所需的电场
hi
xEi
D
XDi
压电陶瓷
1
整体概述
概况一
点击此处输入相关文本内容 点击此处输入相关文本内容
概况二
点击此处输入相关文本内容 点击此处输入相关文本内容
概况三
点击此处输入相关文本内容 点击此处输入相关文本内容
2
压电陶瓷
压电陶瓷的基本物理性能 压电陶瓷的应用 BaTiO3系压电陶瓷 PbTiO3系压电陶瓷
Pb(Ti,Zr)O3系压电陶瓷
介电常数张量元 ij = ji 应变 xij = xji 压电常数 dijk = dikj
18
压电陶瓷的介电常数
对各向同性介质， ij 为标量 对各向异性介质， ij 为二阶张量
11 12 13
ij 21
22
23
31 32 33
19
压电陶瓷的介电常数
三斜晶系： －－6个独立分量
11 12 13
xi = sij Xj, 或 Xi = cij xj
16
压电陶瓷的介电常数
各向同性的介质，E矢量与D矢量同向
晶体具有各向异性－晶体的物理性质用张量表示，如介电常数是
2阶张量：
Di = ij Ej ( i, j = 1,2,3)
D1 = 11 E1 + 12 E2 + 13 E3
3
Di ij Ej i1