小型化大功率压电陶瓷变压器受到人们的青睐

近年来,压电陶瓷变压器应用于彩色液晶显示背光电源的开发研究较为盛行。由于压电陶瓷变压器比电磁型变压器具有小型、高效、高升压比等突出优点,受到人们的青睐。 最近,日本 NEC公司为满足压电陶瓷变压器小型化和大功率化的要求,致力于大功率压电材料的研究,采用所开发的大功率压电材料,现已研制成功了输出功率大于 10W的压电陶瓷变压器。 新开发的大功率压电材料所研制成的多层型压电变压器,具有小型、高升压比等优点,其输出功率可大干 10W以上,不仅适用于彩色液晶的背光电源,亦可应用于复印机、传真机、图象扫描器 (析象仪…     

多层压电陶瓷的相关基础科学问题

多层压电陶瓷是一种重要的换能材料,具有优良的机电耦合效应和对外场响应迅速且体积小、驱动电压低的特点,在机电换能及自动控制等领域得到了广泛应用.本文概述了多层压电陶瓷的几个基础科学问题,包括:无铅压电陶瓷材料、高温压电陶瓷材料、晶粒定向技术以及多层压电陶瓷常见的迟滞、疲劳等问题,并总结了各个方面的研究现状和发展前景.     

大功率多层压电陶瓷变压器的新进展

利用新开发成的大功率压电陶瓷材料 ,研制成功了输出功率大于10W以上的大功率多层压电陶瓷变压器 ,其输出效率大于94 % ,升压比为25～30     

多层压电陶瓷变压器等效电路模型及其特性研究

提出了一种新颖的多层压电陶瓷变压器等效电路模型和分析方法。基于多层压电变压器陶瓷片在结构上的电学并联关系，建立了其在电路上的并联表示模型，并把输出电量与输入电量之间的关系用矩阵形式表达，简化了分析过程，为压电变压器的设计提供了一种通用而简单的分析方法。仿真结果验证了该方法的有效性，获得了良好的输入阻抗特性和升压比特性，升压比约为1200。     

压电陶瓷变压器的工作原理及其应用

本文介绍了压电陶瓷变压器的发展、结构、工作原理、特点及其应用。目前,成熟应用的压电陶瓷变压器均为罗森（Ｒｏｓｅｎ）型,利用电能－机械能－电能的转换使电压升高。目前升压比可达５００倍以上。为提高功率及转换效率,日本ＮＥＣ公司推出多层三次罗森型压电变压器。     

走进信息功能陶瓷材料的元器件大观园探密

电子信息技术的集成化和微型化的发展趋势,推动电子技术产品日益向微型、轻量、薄型、多功能和高可靠的方向发展。功能陶瓷元器件多层化、片式化、集成化、模块化和多功能化以及高性能低成本是其发展的总趋势。本文分别综述了信息功能陶瓷材料的元器件（包括多层陶瓷电容器、片式陶瓷电感器、片式微波电容器、集成陶瓷元件;压电陶瓷超声波电机等...     

流延成膜技术制备高性能多层片式压电陶瓷微驱动器研究

采用压电陶瓷延流厚膜成型技术以及厚膜与金属内电极共烧技术制备了逆压电效应下工作的多层片式压电陶瓷微位移驱动器。该器件具有工作电压低,功耗小,响应快,器件尺寸微小型化等特点,适合于微电子及微型机械应用。本课题对该器件与应用密切相关的位移－电压关系及位移蠕变性能,驱动力和使用寿命等性能测试测试和研究。     

Bi0.5Na0.5TiO3基无铅压电陶瓷设计与制备研究的新进展

综述了Bi0.5Na0.5TiO3(BNW)基无铅压电陶瓷体系研究的最新进展,介绍了BNT基无铅压电陶瓷的设计方法及其制备技术.用自洽场离散变分法(self-consult charge-discrete variation-Xa,SCC-DV-Xa)等计算方法可为设计新型BNT基陶瓷提供重要的理论指导.用湿化学法,包括:溶胶-凝胶法、柠檬酸盐法、水热法等,可以合成BNT基纳米粉体,该类方法制备的BNT基粉体具有良好烧结活性,利于致密化烧结,使材料电性能得到改善.用模板晶粒生长技术可获得晶粒生长定向程度很高的BNT基压电陶瓷材料,进而提高材料在特定方向的压电性能.     

极小的压电陶瓷变压器

本文介绍了一种新型的电子陶瓷材料——压电陶瓷材料．以及它在变压器领域中的应用。详细介绍了压电陶瓷变压器的结构、工作原理及广泛的应用。     

Ti不足对Na_（0.5）Bi_（4.5）Ti_（4-x）O_（15）陶瓷性能的影响

用传统固相烧结工艺制备致密Na0.5Bi4.5Ti4-xO15（x=0,0.02,0.04,0.06,0.08）系列铋层结构压电陶瓷,研究该系列陶瓷的微观结构、介电性质和压电性质。结果表明：少量Ti不足可以促进Na0.5Bi4.5Ti4O15陶瓷晶粒长大并使陶瓷的压电性能获得较大提高;随着x增大,陶瓷的压电常数和机电耦...     

Properties of Low‐Temperature Sintering PNN–PMW–PSN–PZT Piezoelectric Ceramics with Ba(Cu1/2W1/2)O3 Sintering Aids

Piezoelectric ceramics Pb(Ni_1/3Nb_2/3)O₃–Pb(Mg_1/2W_1/2)O₃–Pb(Sb_1/2Nb_1/2)O₃–Pb(Zr_0.39Ti_0.61)O₃ with Ba(Cu_1/2W_1/2)O₃ sintering aids were fabricated using economical industrial oxide powders and their piezoelectric, dielectric, and ferroelectric properties were investigated in order to develop low‐temperature sintering ceramics for multilayer piezoelectric actuators. A quadratic formula and the Curie–Weiss law reveal that the ceramics are typical displacive‐type ferroelectric relaxors. The ceramics sintered as low as 900°C have good piezoelectric properties of d₃₃ = 551 pC/N, k_p = 0.52, ε_r = 3583, tgδ = 0.02, and T_C = 161°C, which is much promising to manufacture multilayer piezoelectric transducers.     

KNN-based piezoelectric ceramic multilayer actuators with Ni internal electrodes

On the road of lead-free piezoelectric ceramics into practical applications, the study of Ni-internal-electrode (K, Na)NbO₃-based (KNN-based) multilayer actuators (MLAs) is an important part, possessing the advantages of environmentally friendly and low cost. The Ni-internal-electrode KNN-based MLAs with different layer numbers and layer thicknesses were fabricated via the tape casting method and sintered in the reducing atmosphere. The piezoelectric layers consist of the main KNN-based phase and a trace amount of second phase Mn₄Nb₂O₉. The element diffusion between the Ni electrodes and KNN-based grains is tiny, indicating that Ni is suitable for co-firing with KNN-based ceramics. After sintering, the compressive stress perpendicular to the thickness direction and the “relative tensile stress” parallel to the thickness direction are retained in the MLAs, bringing influences on the piezoelectric and dielectric properties of KNN-based materials. Compared with the bulk ceramics, the prepared MLAs significantly reduce the driving voltages and increase the displacement outputs, which are more applicable to the scenarios of miniaturization and portability. Particularly, the 46-layer actuator shows high displacements of 1580 and 2737 nm under the voltages of 100 and 200 V, respectively. However, the inverse piezoelectric coefficient d₃₃* for each layer of MLAs is still lower than that of the bulk ceramics, indicating that the piezoelectric properties of the KNN-based materials are suppressed. To give full play to the piezoelectric properties of KNN-based materials, more attentions should be paid to the design of reasonable electrode structure and the development of internal electrode paste for MLAs.     

烧结温度对大功率超薄型压电蜂鸣器用压电陶瓷结构和性能的影响

采用轧膜成型工艺制备大功率超薄型峰鸣器用压电陶瓷。该陶瓷是三方／四方相共存PSN—PBZT(0．02Pb(Sb0．5Nb0．5)O3—0．98PbxBa1-z(Zr0.55Ti0.45)O3)压电陶瓷。研究了烧结温度对三方／四方相共存PSN—PBZTB陶瓷性能的影响，利用XRD和SEM研究了烧结温度对其结构的影响。结果表明，随着烧结温度的升高，材料的晶格常数轴率比Ct／at逐渐升高，ar有所降低，同时，材料的晶粒尺才增大，材料的介电常数和机电耦合系数增大。但是，烧结温度太高将手致其介电常数和机电耦合系数降低，这是由于出现玻璃相和游离氧化锆稀释铁电相所致。     

Defect engineering of high‐performance potassium sodium niobate piezoelectric ceramics sintered in reducing atmosphere

Reducing atmosphere fired (K_0.5Na_0.5)NbO₃‐based ceramics open up an important opportunity for manufacturing lead‐free multilayer piezoelectric devices cofiring with the base metal inner electrode. In this study, the effects of sintering atmosphere on the piezoelectric, dielectric, and insulating properties in Sn‐doped (Na_0.52K_0.44Li_0.04)NbO₃ (KNN) were investigated. To establish the relationship between the defect structure and electrical properties, the thermally stimulated depolarization current (TSDC) technique was implemented. The electrical properties degrade severely when the pure KNN ceramics are sintered in reducing atmosphere, compared with the ceramics sintered in air. The reason is that the oxygen vacancy concentration in reduced fired ceramics is much higher than that in air fired ceramics. However, the 0.6 mol% Sn‐doped KNN ceramics sintered in reducing atmosphere exhibit comparable electrical properties to the air fired ceramics. From the TSDC analysis, the reducing atmosphere fired ceramics have approximately the same oxygen vacancy concentration as the air fired ceramics because B‐site substituted Sn works as an acceptor.     

Li2CO3掺杂对0.2PMN-0.8PZT陶瓷的影响

利用铌铁矿预产物合成法,研究不同温度烧结下Li2CO3掺杂对0.2 PMN-0.8PZT压电陶瓷(简称PLC)的相结构和电性能的影响。X射线衍射(XRD)和扫描电镜(SEM)的分析结果表明,掺杂LiCO3的0.2PMN-0.8PZT压电陶瓷经不同温度煅烧后,所有陶瓷样品的相组成均为纯钙钛矿相,并随着烧结温度的升高,PLC的相结构有由四方相向菱方相转变的趋势。通过0.2PMN-0.8PZT压电陶瓷掺杂LiCO3煅烧后的微观形貌、介电常数、压电性能、铁电性能的分析,发现经1200℃烧结的样品的介电和压电性能最佳:介电常数(εr)为38512,室温压电常数(d33)为300 pC/N,剩余极化强度(Pr)为31.3 C/cm2,矫顽电场(Ec)为7.5 kV/cm。     

Ultralow sintering temperature and piezoelectric properties of Bi(Zn1/2Ti1/2)O3−BiScO3−PbTiO3 for low-temperature co-firing applications

Bi(Zn_1/2Ti_1/2)O₃−BiScO₃−PbTiO₃ (BZT−BS−PT) high Curie temperature piezoelectric ceramics were synthesized by the conventional solid-state reaction method. Systematical investigations on the sintering, piezoelectric, and dielectric properties of the piezoceramics have been conducted. It was found that the sintering temperature could be remarkably depressed by varying the compositions in BZT−BS−PT systems. For composition of 11BZT−34BS−55PT ceramic, the sintering temperature is even lowered down to 750°C without any extra additions of sintering aids. Meanwhile, the ceramic sintered at this ultralow temperature presents dense microstructure with relative density up to 97%, as well as optimal properties of piezoelectric coefficient d₃₃ of 336 pC/N and Curie temperature of 415°C. The mechanism of low sintering temperature may be ascribed to the low melting point bismuth-based components in BZT−BS−PT solid solutions. Furthermore, 11BZT−34BS−55PT multilayer ceramics have been co-fired at 750°C with Ag internal electrodes. The dense structures, low cost, and optimal comprehensive properties of the co-fired multilayers illustrate obvious advantages of the ultralow sintering temperature in LTCC devices, implying promising applications of this Bi(Zn_1/2Ti_1/2)O₃−BiScO₃−PbTiO₃ high Curie temperature ternary system.     

Fabrication and properties of (Ba0.85Ca0.15)(Ti0.9Zr0.1)O3 ceramics and their multilayer piezoelectric actuators

The lead‐free ceramics with nominal composition (Ba_0.85Ca_0.15)(Ti_0.9Zr_0.1)O₃ (BCTZ) were prepared by a conventional solid‐state reaction combined with a liquid precursor mixing method. Structural, dielectric, piezoelectric, and ferroelectric properties of the ceramics were systematically investigated. Excellent electrical properties of T_c ~ 101°C, tanδ ~ (0.003–0.05), k_p ~ 0.46, d₃₃ ~ 560 pC/N, P_s ~17 μC/cm² and a large strain of 0.43% were reproducibly obtained for the BCTZ ceramics. In addition, BCTZ‐based monolithic multilayer piezoelectric actuators were successfully fabricated by alternately laminating the claimed piezoelectric ceramics and internal‐binder. The actuators show large displacements under low driven voltage. These results highlight that the BCTZ ceramics are excellent candidate for multilayer piezoelectric devices.     

Low sintering temperature,large strain and reduced strain hysteresis of BiFeO3–BaTiO3 ceramics for piezoelectric multilayer actuator applications

BiFeO₃–BaTiO₃ solid solutions with pseudo-cubic phase have received a lot of attention because of their large strain for potential piezoelectric multilayer actuator applications. However, the high sintering temperature, large dielectric loss and severe strain hysteresis hindered their real applications. In this work, Li₂CO₃ sintering aid modified 0.64BiFeO₃-0.36BaTiO₃ (BF-BT-L) ceramics were prepared by the high-temperature sintering method, and their phase structure, microstructure, electric properties as well as strain were investigated. With the increase of Li₂CO₃ content, the sintering temperature decreases down to 900 °C, and the relative density increases up to 96%. Of particular importance is that the dielectric loss and strain hysteresis of BF-BT-L ceramics are reduced by 40% and 47%, respectively, while BF-BT-L ceramics shows a large strain of 0.3% (60 kV/cm). The sintering temperature, relative density, strain, large-signal d₃₃* and strain hysteresis of BF-BT-L ceramics are 900 °C, 96.5%, 0.3%, 500 pm/V, and 25% respectively. The reduced dielectric loss and strain hysteresis result from the enhanced relative density, decreased concentration of defects and partial phase transition from partial pseudo-cubic to rhombohedral one by Li₂CO₃ additions. Furthermore, BF-BT-L ceramics show positive temperature dependent strain, with large d₃₃* and strain hysteresis of 675 pm/V and 15% at 200 °C respectively. The simple composition, low sintering temperature, large strain and reduced strain hysteresis of BF-BT-L ceramics indicate that they are promising candidates for high-performance and lead-free piezoelectric multilayer actuator applications.     

High-temperature multilayer actuators based on CuO added BiScO3–PbTiO3 piezoceramics and Ag electrodes

High-temperature multilayer actuators based on Cu doping 0.367BiScO₃–0.633PbTiO₃ ceramic slices and Ag electrodes were prepared by low-temperature co-firing technology. The 0.3 wt% CuO addition has effectively reduced the sintering temperature of the ceramic from ~1080 to 930°C, thus the multilayer actuator were sintered at 930°C which is lower than the Ag melting point, that is, 961°C. The 4.3 mm thick multilayer actuator is composed of a series of ~44-μm-thick ceramic slices and ~2-μm-thick Ag electrodes. As a result, a ≥0.13% strain with nm-scale preciseness can be produced in the actuator by 200 V driving voltage not only at room temperature but also at a high temperature up to 200°C. This actuator is essential for industrial machinery that requires nm-scale position control at 20-200°C.     

Sr(Cu1/2W1/2)O3改性PZT压电陶瓷的性能研究

制备了钨铜酸锶掺杂PZT三元体系压电陶瓷,测量了不同烧结温度和不同组成的材料的压电常数值,以压电常数为依据,确定了不同组成的材料的最优烧结温度及在最优烧结温度下材料的压电常数.研究了钨铜酸锶的掺杂量对材料机电耦合系数和机械品质因数的影响.并对不同组成的材料进行了XRD和SEM分析,研究了材料的物相组成和微观结构对材料性能的影响.讨论了Sr2+,W6+,Cu2+离子对PZT压电陶瓷进行改性的作用机理.实验结果表明,钨铜酸锶可对PZT材料进行较好的改性作用,使材料的压电常数提高到570pC/N.