锆钛酸铅纳米陶瓷粉体制备方法的研究进展

PZT压电陶瓷因其具有良好的铁电、压电和介电性能,已成为电子、航空航天、医疗、生物等各技术领域不可缺少的重要功能材料。综述了制备PZT纳米粉体的各种方法,评述了固相法、液相包裹法、水热法、沉淀法和溶胶凝胶法的制备工艺特点,并探讨了PZT纳米粉体制备方法的发展趋势。     

锆钛酸铅PZT压电陶瓷的制备及其性能研究

以具有优良压电性能的二元系固溶体锆钛酸铅(PZT)材料为研究对象,以其制备工艺、结构和性能作为主要研究内容,通过高温固相烧结方法对PZT的合成规律进行了研究,使用XRD谱、Raman谱结构表征手段和XPS、热膨胀、介电测量等物性测试技术研究了它们的晶体结构、晶粒尺寸与性能的关系,以及合成条件对铁电材料的微观结构和性能的影响。     

PZT压电陶瓷粉体合成的研究进展

本文介绍了固相法和液相法合成PZT压电陶瓷粉体的研究现状，分析了各种合成方法的特点，指出了PZT粉体合成研究中存在的问题和发展方向。     

两步沉淀法合成锆钛酸铅相形成的反应机理

用X射线衍射(X-ray diffraction, XRD)研究了两步沉淀法合成钙钛矿相锆钛酸铅(PbZrxTi1-xO3,PZT)的相形成机理和准结晶学相界.结果显示:两步沉淀法合成的PZT粉体为纯钙钛矿相,低温煅烧时,优先形成菱方相PZT.XRD分析结果表明:900℃煅烧合成的PZT粉体,摩尔组成在0.47≤x≤0.55范围时,菱方相和四方相共存,两相相等的组成点为x=0.515.基于PbO-PZT和PZT-ZrxTi1-xO3(ZT)2个反应界面以及离子扩散,提出了关于两步沉淀法合成PZT相形成反应机理的模型.     

Pb(Zr0.53Ti0.47)O3陶瓷超细粉体制备及分散研究

用化学共沉淀法合成了陶瓷Pb(Zr0.53Ti0.47)O3超细粉体,以聚乙二醇(PEG)为分散剂对所得粉体进行分散。通过X衍射、扫描电镜分析,研究了合成条件和煅烧温度对PZT粉体性能的影响。结果表明,随着煅烧温度的升高,PZT超细粉晶化度提高,一次晶粒尺寸增加,而二次粒子尺寸却减小。当分散剂分子量为10000,用量为1%时,得到分散良好的超细粉体。测定了用合成的粉体烧结的PZT陶瓷的压电性能。     

水热法合成(K,Na)NbO_3陶瓷粉体及其压电性能研究

利用水热法在碱性溶液中合成了具有钙钛矿结构的(K,Na)NbO_3无铅压电陶瓷粉体,研究了初始溶液中K+的含量对产物晶相、形貌以及化学组成的影响。采用X射线衍射仪以及扫描电镜对产物的结构和形貌进行了表征,利用X荧光分析仪对粉体的化学组成进行了精确分析。实验结果表明:随着初始溶液中K~+含量的变化,有两相钙钛矿(K,Na)NbO_3粉体生成,在溶液中K~+的反应活性低于Na~+。然后,将水热合成的K_(0.58)Na_(0.42)NbO_3粉体采用传统固相烧结制备陶瓷材料,其结构较致密,压电常数d_(33)达到94 pC/N。     

铁电陶瓷颗粒填充压电复合材料的微结构与性能

采用模塑工艺制备了含铁电陶瓷PZT颗粒填充的PZT／P（VDF－TrFE）压电复合材料，用差热分析研究并确定了复合材料的固化工艺参数，测试并研究了压电复合材料的电性能和显微结构，结果表明，随着PZT质量百分比的增加，电性能参数逐渐增大，当PZT的质量百分比达到85％时，介电常数ε和压电常数d33值最大，铁电陶瓷颗粒分布均匀，当PZT含量较低时，两相材料界面结合良好，而当PZT含量达到90％时，气孔则明显增多，这就是导致复合材料的介电常数和压电常数在PZT高含量区下降的主要原因。     

两步沉淀法合成钙钛矿相锆钛酸铅粉体及其相形成机制

用两步沉淀法低温合成了纯钙钛矿相锆钛酸铅(PbZr0.52Ti0.48O3,PZT)粉体,并利用差热分析测定了合成粉体的反应活化能,从动力学上研究了钙钛矿相PZT的形成机制.结果表明:两步沉淀法合成PZT粉体遵循连续反应机理,在热处理过程中,前驱体粉体在500 ℃处理后主要形成钙钛矿相,并伴有少量焦绿石相.经600 ℃煅烧后则完全转化为钙钛矿相.这是由于形成焦绿石相的反应活化能远大于焦绿石相转化为钙钛矿相的反应活化能,因此500℃处理后生成的少量焦绿石相在600 ℃处理后完全转化为钙钛矿相.     

大磁电系数Pb(Zr_(0.52)Ti_(0.48))O_3膜–CoFe_2O_4陶瓷复合结构

通过溶胶–凝胶法在高致密度的钴铁氧体陶瓷片上制备锆钛酸铅(PZT)薄膜。在该复合结构中,PZT膜采用了较低的处理温度,从而有效避免了传统陶瓷共烧过程中出现的界面反应。样品表现出较好的铁电、介电、压电和磁电性能,并且面内磁电耦合系数可达58 m V/(cm?Oe)。     

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。     

Improved piezoelectric properties of Pb(Zr0·70Ti0.30)O3 ceramics doped with non-polar bismuth manganite

This report documents the electrical features of (1-x) Pb(Zr_0·70Ti_0.30)O₃–x BiMn₂O₅ ceramics with x = 0–0.05 (PZT–BM). A structural disorder was introduced by doping with non-polar bismuth manganite (BM) to increase the chemical disorder in PZT ceramics, which is one of the reasons for its marked piezoelectric properties. The chemical disorder was confirmed using scanning electron microscopy. The rhombohedral symmetry of a crystal lattice was determined using the XRD powder test. To assess the influence of BM dopant on the electric properties of PZT, dielectric spectroscopy was performed at a frequency f = 1 kHz–1 MHz and in a temperature range of 290–680 K. Several effects on the dielectric characteristics were induced by the addition of BM, including the shift and diffuseness of the transition from the ferroelectric to the paraelectric phase and the diffuseness of the transition between two ferroelectric phases. The electrical conductivity increased as the BM content increased. Piezoelectric studies have shown that 0.99 PZT–0.01 BM ceramics exhibit better piezoelectric properties and higher permittivity than pure PZT ceramics. The 0.99 PZT–0.01 BM piezoelectric coefficient d₃₃ increased by approximately 30% compared with pure PZT.     

Laser sintered ceramic coatings of PZT nanoparticles deposited by Inkjet Printing on metallic and ceramic substrates

Lead zirconate titanate (PZT) Pb(ZrxTi1-x)O₃ is one of the most studied perovskite type ferroelectric materials due to its excellent dielectric, piezoelectric and ferroelectric properties. PZT particles and a PZT precursor were synthesized using a chemical method. A vehicle was added to the synthesized particles and precursor for obtaining two inks with appropriate rheological properties to be printed by Inkjet Printing. The use of an 80?µm diameter nozzle made necessary the utilization of an energetic ball milling for assuring the dispersion of small PZT particles in the ink. After ball milling nanoparticles of 150?nm diameter were obtained. These inks were deposited on alumina and steel substrates followed by sintering using a pulsed laser of 1064?nm wavelength. The work shows the effect laser sintering has on, both inks, the one containing PZT nanoparticles and that one based on the PZT precursor. Laser processing was optimized in order to generate suitable films to be subsequently poled. The effect of poling on these films was also studied and their piezoelectric properties were measured by a compression test. The microstructural characteristics of these films were obtained by SEM and X ray diffractometry.     

Piezo and dielectric properties of PHB–PZT composite

Flexible piezoelectric composite films made of poly(3‐hydroxybutyrate) (PHB) in powder form and lead zirconate titanate (PZT) ceramic powder were obtained by mixing both powders and pressing at 180°C. The effect of PZT on PHB crystallization was investigated using differential scanning calorimetry (DSC). The relative dielectric constant and dielectric loss factor were analyzed by dielectric spectroscopy and the α‐relaxation of amorphous phase of PHB was observed. After suitable polarization, the composite film displayed piezoelectric activity indicating the possibility of using that material as a sensor. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers     

Sintering and Piezoelectric Properties of Co-Fired Lead Zirconate Titanate/Ag Composites

Lead zirconate titanate (PZT) ceramics were co-fired with pure Ag powders at 1200°C for 1 h, and the ferroelectric and piezoelectric properties of the resultant PZT/Ag composites were evaluated, aimed at potential applications in functionally graded piezoelectric actuators with enhanced mechanical reliabilities. In the range of 1–15 vol% Ag concentration, pure Ag powder remained as the second phase in the composites, and a small quantity of Ag entered into the crystal lattice of PZT and slightly increased the lattice constants of a and c . The Ag powders were found to aggregate together and grow to larger particles in the composites. The ceramic grains grew from an initial size of 1.5 μm for monolithic PZT to 2.5 μm for the PZT/Ag composites, and the grain size was almost the same for various Ag concentrations. It was found that the ferroelectric and piezoelectric properties decreased when Ag was added to PZT. In the range of 1–15 vol% Ag concentration, the remanent polarization P _r decreased from 38 to 27 μC/cm², the piezoelectric constant d ₃₃ decreased from 394 to 105 pC/N, and the planar electromechanical coupling factor k _p decreased from 0.69 to 0.15, respectively. These piezoelectric properties of the present PZT/Ag composites were compared with the results reported for PZT/Pt composites, and discussed in relation to microstructural features.     

Effects of thermal strain on electric properties of lead zirconate titanate thin films upon LaNiO3 coated base metal plates

Electric properties for ferroelectric lead zirconate titanate (PZT50/50, 45/55, 40/60, 30/70) thin films on base metal plates with different thermal expansion coefficient (TEC) were calculated by a phenomenological model. Results show that when the TEC of substrates increases, dielectric constant, tunability and piezoelectric coefficient d₃₃ of all PZT thin films with tetragonal phase are decreased due to the larger compressive thermal strain. PZT50/50 thin films deposited on smaller TEC substrates can achieve higher dielectric constant, tunability and d₃₃. The computed dielectric constant of PZT50/50 thin films is in accordance with the measured results from sol-gel experimental process, and the trend of dielectric constant of PZT films adjacent to morphotropic phase boundary (MPB) derived from some references also agrees with that from calculation. These results suggest that higher tunability and d₃₃ of PZT films can be obtained by choosing smaller TEC substrates.     

Effects of pore shape and porosity on the properties of porous PZT 95/5 ceramics

Porous lead zirconate titanate (PZT 95/5) ferroelectric ceramics were prepared by sintering compacts consisting of PZT and pore formers. The piezoelectric, dielectric and ferroelectric properties of porous PZT ceramics were investigated as a function of pore shape and porosity. Piezoelectric coefficient (d₃₃), dielectric constant (ɛ₃₃) and remnant polarization (P_r) decreased with an increase in porosity, and the porous PZT ceramics with spherical pores exhibited better properties than that with irregular pores. Furthermore, the electrical conductivities of PZT ceramics were investigated to explain the phenomena that porous PZT ceramics exhibited lower dielectric loss (tan δ) than dense PZT ceramics in the temperature range from 250 to 500 °C.     

Higher permittivity of Ni-doped lead zirconate titanate,Pb[(Zr0.52Ti0.48)(1-x) Nix]O3, ceramics

The paper reports highest obtained dielectric constant for Ni-doped Lead Zirconate Titanate [PZT, Pb(Zr_0.52Ti_0.48)O₃] ceramics. The Ni-doped PZT ceramic pellets were prepared via conventional solid-state reaction method with Ni content chosen in the range 0–20?at%. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy were employed to investigate the crystal structure of the prepared ceramics. The X-ray diffraction analysis indicated that the ceramic pellets had crystallized into tetragonal perovskite structure. A minute displacement of XRD peaks was detected in the diffraction spectra of Ni-doped PZT ceramic samples which when examined by size-strain plot (SSP) method revealed presence of homogenous strain that decreased with increase in concentration of Ni. In FTIR the maximum absorption at 597?cm^?1, 608?cm^?1, 611?cm^?1, 605 and 613?cm^?1 for Ni?=?0, 5, 10, 15 and 20?at%, respectively, confirmed the formation of perovskite structure in all the compositions and the slight shift suggests decrease in cell size on doping. The values of dielectric constant (ε′) & tanδ as a function of frequency and temperature were measured for the prepared ceramics and it revealed highest ever reported dielectric constant for Ni - doped PZT with Ni?=?5?at%. The dielectric variation with temperature exhibited a diffused type ferroelectric–paraelectric phase transition for the doped samples. Also, the maximum dielectric constant value (ε′_max) decreased while the phase transition temperature increased with increase in doping concentration of Ni. The estimated activation energy of different compositions was found to increase from 0.057 to 0.068?eV for x?=?0.00 to x?=?0.20 in ferroelectric phase. The piezoelectric, ferroelectric and magnetic properties were also investigated.     

含Pt金属芯压电陶瓷纤维的微观结构和电学性能

以传统固相法制备的0．55Pb（Ni1/3Nb2／3）O3-0．45Pb（Zr0.3Ti0.7）03（PNN-PZT）压电陶瓷粉体为原料,采用挤压成型工艺制备含Pt金属芯压电陶瓷纤维。以PbTi03作为保护粉体,对纤维坯体进行1200℃不同时间（0．5、1．0h和2．0h）的烧结处理。利用X射线衍射仪、扫描电子显微镜、阻抗分析仪和铁电分析仪等研究了烧结时间对纤维微观结构、压电性能和铁电性能的影响。结果表明：在烧结时间范围内制备的压电陶瓷纤维为单一钙钛矿结构,未发现焦绿石相或其他杂相;随烧结时间增加,陶瓷纤维晶粒尺寸增大,压电和铁电性能明显提高。在1200℃保温2．0h制备的压电陶瓷纤维电学性能较好,压电常数（西1）、相对介电常数（曲、介电损耗（tanδ）和矫顽场（＆）分别为-145pC／N、3313、2．6％和0．27kV／mm。介电温谱结果表明：该陶瓷纤维的特征Curie温度为125℃,峰值相对介电常数为8093。