Piezoelectric Properties Of PZT Ceramics Research Articles

Effects of Li2CO3–CuO addition on the sintering behavior, dielectric and piezoelectric properties of PZT ceramics

Effects of Li2CO3–CuO addition on the sintering behavior, dielectric and piezoelectric properties of PZT ceramics

Effect of the slurry composition on the piezoelectric properties of PZT ceramics fabricated via materials extrusion 3D printing

Herein, the effect of the binder content in lead zirconate titanate (PZT) slurry has been systematically studied to improve the piezoelectric properties of PZT ceramics prepared via material extrusion 3D printing. For smooth printing, a slurry with a binder concentration ranging from 6 to 12 wt% was proposed. The porosity of the green body first decreased and then increased with an increase in the binder concentration, and the minimum porosity was obtained when the binder concentration reached 10 wt%. Samples with increased density were obtained after debinding and lead-rich atmosphere sintering. PZT piezoceramics fabricated using a binder content of 10 wt% exhibit the maximum relative density (96.9%), largest piezoelectric constant (342.6 pC/N) and dielectric constant (1621). Based on the above process, the wood pile structure and helical twentytetrahedral structural components were successfully fabricated using the material extrusion process. This research lays the foundation for the engineering application of 3D printing to fabricate high-performance piezoceramics with complex shapes.

Dielectric, Ferroelectric and Piezoelectric Properties of PZT Ceramics by ZnO Doping

The phase structure, microstructure and electrical and electromechanical properties of ZnO-doped PbZr0.52Ti0.48O3 (PZT) ceramics were investigated. Piezoelectric ceramics were prepared by the conventional solid-state method. The XRD results indicate that it is the solid solution between the PZT and ZnO. SEM results indicate that the grain size increases and then excessive Zn ions concentrated in the grain boundaries of the ceramics and breaked grain boundaries. The addition of ZnO improved the Curie temperature, and It has a better temperature stability for 0.1 mol% doped PZT ceramics.

Improved sintering activity and piezoelectric properties of PZT ceramics from hydrothermally synthesized powders with Pb excess

In this work, Pb(Zr, Ti)O3 (PZT) powders were prepared by traditional hydrothermal method and solid state reaction. Subsequently, PZT ceramics were sintered and their electric properties (including piezoelectric coefficient d 33, electromechanical coupling coefficient k p and mechanical quality factor Q m) as a function of sintering temperature (1125–1250 °C) were comparably studied. Given that the Pb deficiency may exist in the hydrothermally synthesized PZT powders, effects of Pb excess (0, 20 and 80 mol%) in the hydrothermal precursor on their sinterability were also involved. The hydrothermally synthesized PZT powders with 80 mol% Pb excess showed the highest sintering activity, and their electric properties peaked at 1175 °C (d 33 = 225 pC/N, k p = 0.446, Q m = 300). It’s demonstrated that A-site deficiency may degrade the sintering activity of PZT powders, and hydrothermal synthesis of PZT powders with appropriate Pb excess was the compromising pathway to increase their sinterability, decrease the sintering temperature and lessen the volatilization of Pb ion in the fabrication of widely applied PZT ceramic.

Role of charged defects on the electrical and electromechanical properties of rhombohedralPb(Zr,Ti)O3with oxygen octahedra tilts

Oxygen octahedra tilting is a common structural phenomenon in perovskites and has been subject of intensive studies, particularly in rhombohedral Pb(Zr,Ti)O3 (PZT). Early reports suggest that the tilted octahedra may strongly affect the domain switching behavior, dielectric and piezoelectric properties of PZT ceramics. In a way similar to that proposed for tilts, however, charged defects, associated with oxygen vacancies, may also inhibit the motion of the domain walls, resulting macroscopically in pinched hysteresis loops and reduced piezoelectric response. Here, we revisit the early studies on rhombohedral PZT ceramics with tilted octahedra by considering a possible role of both tilts and charged defects on domain-wall motion. We show that the observed pinched hysteresis loops are likely associated with the presence of defect complexes containing charged oxygen vacancies, and not tilts as suggested in some cases. Regardless of the presence or absence of long-range ordered tilts in rhombohedral PZT, the effect of charged defects is also prominent in weak-field permittivity and piezoelectric properties, particularly at sub-Hz driving conditions where the conductivity, related to the motion of oxygen vacancies, gives rise to strong frequency dispersion.

Enhanced piezoelectric properties of PZT ceramics prepared by direct coagulation casting via high valence counterions (DCC–HVCI)

Lead zirconate titanate (PZT) ceramics were prepared by direct coagulation casting via high valence counterions (DCC–HVCI) using magnesium citrate as a coagulating agent assisted by the hydrolysis of glycerol diacetate. The colloidal behavior of PZT suspensions was evaluated by measuring the zeta potential and the viscosity. The dispersant content and solid loading were optimized to prepare concentrated PZT suspension. The results indicated that PZT suspension with solid loading up to 56vol% can be prepared by the addition of 0.5wt% ammonium polyacrylate at pH=10.6. The critical coagulation concentrations of magnesium and lead in 56vol% PZT suspensions are 15 and 35mM, respectively. The viscosity of 56vol% PZT suspensions with 0.5–1.0wt% magnesium citrate and 2vol% glycerol diacetate is higher than 30Pas at 60°C for 30min which is sufficient to coagulate the suspensions. The coagulating time is 60–90min at 50–70°C. The compressive strength of the coagulated wet samples decreases with the increase of coagulating temperature, but increases with the increase of magnesium citrate content. The strength is in the range 1.5–2.8MPa which is sufficiently high for demolding and handling without deformation. Dense PZT ceramics sintered at 1250–1280°C show homogeneous microstructures with relative densities of 99.2–99.7% and good piezoelectric properties compared with a traditional die pressing method.

Influence of Complex Additives on the Piezoelectric and Dielectric Properties of PZT Ceramics

The effects of the complex donor and acceptor additives on the microstructure, piezoelectric and dielectric properties of PZT (Zr/Ti=53/47) ceramics were studied. A complex doping with the soft (La+3 and Nb+5) and hard (Fe+3 and/or Mn(+2,+3 or +4)) ions has been adopted. The complex doping of two or more elements is expected to combine the properties of donor and/or acceptor doped PZT, which could exhibit better stability or improved piezoelectric properties than those of the single element doped PZT. The complex doping caused various compensation effects for the piezoelectric properties of PZT ceramics; Mn addition to the La/Nb and Fe doped PZT composition led to the improved piezoelectric properties, i.e., enhanced Qm with remaining considerably high kP.

The effect of Li2CO3 addition on the structural, dielectric and piezoelectric properties of PZT ceramics

A detailed systematic study of the effect of Li2CO3 addition on the structural, dielectric and piezoelectric properties of the PZT (Zr/Ti =50/50) ceramics in the morphotropic phase boundary (MPB) region was carried out. The addition of Li2CO3 in the PZT system resulted in the improved sinterability and densification of the ceramics. 0.2wt% Li2CO3 addition was found to be optimum for obtaining better dielectric and piezoelectric properties in the PZT ceramics. It was further seen that the addition of Li2CO3 shifted the MPB of the ceramics towards the tetragonal phase. The Zr/Ti ratio was hence, varied to regain the MPB in the PZT ceramics with an intention to obtain superior dielectric and piezoelectric properties.

Dielectric and piezoelectric properties of PZT ceramics doped with strontium and lanthanum

PZT based piezoelectric ceramics obtained by doping with various levels of Sr2+ and La3+, designated as PSLZT, were prepared by conventional processing techniques. The effects of Sr2+ and La3+ additions, and that of the Zr/Ti ratio on microstructure, on phase constitution, and on the dielectric and piezoelectric properties were investigated. XRD data revealed that all PSLZT compositions had perovskite structure in which increasing Sr and/or decreasing Zr/Ti ratio increased the tetragonality. In PSLZT ceramics the morphotropic phase boundary (MPB) appeared as regions extending from Zr/Ti ratio of 52/48 to 58/42. Among all compositions studied, the PSLZT ceramic having 5at% Sr2+ and 1at% La3+ with a Zr/Ti ratio of 54/46 exhibited a peak piezoelectric strain coefficient of d33=640 pC/N with attending dielectric and electromechanical parameters K33T=1800, kp=0.56, Qm=70, and tanδ=1.55%.

Mechanical Reinforcement and Piezoelectric Properties of PZT Ceramics Embedded with Nano-Crystalline

The double-scale lead zirconate titanate (PZT) piezoelectric ceramics were prepared by the solid state processing with PZT nano-crystalline and micro-powder. The microstructures, electrical and mechanical properties of the double-scale PZT are investigated. All the sintered ceramics exhibit a single perovskite structure and the grain size of the double-scale PZT reduces due to the incorporation of PZT nano-crystalline. Compared to normal PZT, the mechanical properties increase significantly and the piezoelectric properties decrease slightly. Mechanisms responsible for the reinforcement of the double-scale PZT are discussed.

Dielectric and piezoelectric properties of PZT ceramics with anisotropic porosity

Pb(Zr,Ti)O3 ceramics with homogenous, anisotropic porosity were manufactured and the influence of the anisotropic porosity on the dielectric and piezoelectric properties was studied. Image analysis allowed the quantification of the preferential orientation and the calculation of the distribution of the aspect ratio of the pores. The different dependence of the permittivities $$\varepsilon _{33}^T $$ and $$\varepsilon _{11}^T $$ on the porosity content demonstrates that the population of pores is constituted of a high volume of pores with low aspect ratio and a low volume of pores with high aspect ratio. In view of the quantitative results obtained on the microstructure, an explanation of the frequency dependence of the dielectric and piezoelectric behaviour is suggested. Furthermore, the higher d31 piezoelectric coefficient in the material with anisotropic pores than in material with isotropic pores is related to higher effective fields which are a consequence of the enhanced longitudinal mobility of the material under transverse stress.

Effect of Lead Content and B-Site Substitutions on Dielectric and Piezoelectric Properties of PZT Ceramics

The behaviour of the dielectric and piezoelectric properties of doped PZT ceramics, with variable lead content, has been investigated from –50oC to room temperature. The PZT materials were prepared by the oxide technique and samples were sintered as pellets, at various temperatures. Niobium and lithium ions have been substituted for Ti4+, Zr4+ in the PZT matrix, and a small amount of Bi2O3 was added to cause A-position vacancies. The lead content in the four materials prepared varies in a narrow range, from 0.97 to 1.029 lead atoms, while the concentration of all other components are maintained constant. The microstructure of samples, evaluated by SEM technique and XRD analysis evidenced the presence of the tetragonal phase characteristic for the PZT 52/48. The dielectric and piezoelectric c onstants measured on poled samples depends on the sintering temperature, defects and domain walls, lead content.

Dielectric properties of Pb(Mg1/3Nb2/3)O3-PbTiO3/polyurethane 0-3 composites

In recent years, lead-based relaxor materials have been much researched for diverse applications. These include devices such as ferroelectric random access memory (FeRAM) [1], multilayer ceramic capacitor (MLCC) [2], ultrasonic transducer [3], and display devices [4] due to their high dielectric constant [5]. Composite piezoelectric materials are an especially useful choice for transducers such as medical ultrasound devices. These composites show voltage charge constant g33values that lead to the increased sensitivity. Moreover, the matching efficiency of acoustic impedance also improves due to the low density and the low velocity of composite material [6]. This paper considers the dielectric properties of Pb(Mg1/3Nb2/3)O3PbTiO3/polyurethane 0–3 composites not yet reported, showing the dependence of those properties. A 0–3 connectivity, a three dimensionally connected polymer matrix filled with discrete loaded piezoelectric ceramic particles, was considered. Historically, various connectivity patterns of PZT (lead zirconate titanate)-polymer composites have been studied to improve the piezoelectric properties of PZT ceramics [7, 8]. J. T. Wang et al. reports the composites have been studied using rigid epoxy with Pb(Mg1/3Nb2/3)O3PbTiO3 (PMN-PT) [9]. In contrast, J. Su et al. [10] states that polyurethane rubber produces 0.85% strain when an electric field of 7 MV/m is applied to a 0.1 mm thick sample. Moreover, a polyurethane composite, rather than epoxy composite, decreases stress inside the piezoelectric materials [11]. Therefore, piezoelectric composites with 0–3 connectivity were fabricated from PMN-PT powders and polyurethane rubber. These composites were investigated for dielectric properties with variations in active particle and PMN-PT/polyurethane interfacing. For the study, PMN-PT calcined powders were used as PMN-38 purchased from TRS Ceramics, Inc., PA, USA. The powders were pressed to form a disk of 25 mm × 1 mm under 100 MPa pressure. Following binder burn out at 500 ◦C, the pellets were then sintered at 1100 ◦C and 1150 ◦C for 2 h with the heating rate 50 ◦C/h and natural cooling in the furnace. Excess PbO (10 wt%) and PbZrO3 were added as PMN-PT source powders. The pellets were put on the platinum foil in a closed alumina crucible, and an oxygen atmosphere was employed for sintering. The sintered disks were crushed to powder with a mortar and pestle. The prepared powders were obtained by first sieving with

Effects of addition of MnO on piezoelectric properties of lead zirconate titanate

The effects of manganese addition on the piezoelectric properties, microstructure, sintering characteristic and Curie temperature have been studied for Pb(Zr,Ti)O3 (PZT) ceramics. The valence states of manganese are measured by Electron Spin Resonance (ESR). Those studies show that manganese coexist mainly in the way of Mn2+ and Mn3+ in PZT ceramics. When the concentration of Mn ion is below 0.5 mole%, it is preferentially incorporated in the lattice Pb site in Mn2+ or Mn3+, which gives rise to the increase of Kp and d33. In the intermediate concentration region of 0.5–1.5 mole%, Mn ion will be incorporated in the lattice of (Ti, Zr) site in Mn3+ acted as acceptor, which increases Qm without causing large changes of Kp and d33. When the concentration of Mn ion is larger than 1.5 mole%, it will accumulate at the grain boundaries and give rise to the decrease of piezoelectric properties of PZT ceramics. Small amount of Fe may decrease the solubility limit of Mn ion in PZT ceramics and it may also prevent the oxidation of Mn2+ and Mn3+.

Influence of poling conditions on the piezoelectric properties of PZT ceramics

The influence of the poling temperature, the poling electric field, the poling time and the distance between electrodes on the dielectric constant ɛr and the electro-mechanical coupling factor kr of PZT were investigated using a statistical analysis method. Interactions between various factors affecting ɛr and kr parameters were found particularly, with regard to the poling temperature. The kr value of PZT is influenced more by the absolute voltage than by the applied electric field strength.

The effect of isostructural seeding on the microstructure and piezoelectric properties of PZT ceramics

Pechini’s method was used to prepare lead titanate zirconate with Zr/Ti ratio equal to 53/47. X-ray diffraction data revealed the presence of a rhombohedral phase, rich in zirconium, due to difference in carbonate stabilities, in PZT ceramics calcined at 600°C. Infrared spectroscopy presented COO- bonds in the 1400 cm -1 region, which disappeared after calcining at 700°C. Seeds with rhombohedral (PZT 57/43) or tetragonal structure (PZT 45/55) were added to the precursor. The microstructure was differentially influenced by the nature of seed particles. Rhombohedral nuclei promoted preferential crystallization of lead zirconate. This heterogeneity directly reflected on values of k p and d 33.

Piezoelectric Properties of PZT Ceramics Sintered at Low Temperature with Complex-Oxide Additives

Low temperature firing of 0.5wt% MnO2-added Pb(Zr0.53Ti0.47) O3 (PZT) ceramics is desirable for suppressing the volatilization of PbO. The effect of two additives, BiFeO3 and Ba(Cu0.5W0.5)O3, both with the perovskite-type structure on the sintering temperature and piezoelectric properties of the PZT ceramics has been investigated. The addition of two complex oxides lowered the sintering temperature and improved piezoelectric properties. Simultaneous addition of CuO improved the piezoelectric properties. A 0.92PZT-0.05BiFeO3-0.03Ba(Cu0.5W0.5)O3 ceramics including 0.08wt% CuO ceramics sintered at 935°C for 30min gave the following characteristics; Kp=47.0%, Qm=950, d33=236×10-12C/N, eT33/e0=850, tanδ=1.0%, Tc=290°C, and bulk density=7.66g/cm3.

Piezoelectric properties of Pb(Zn1/3Nb2/3)O3-contained PZT thin plate

Abstract Pb(Zn1/3Nb2/3)O3 (PZN) ceramic is used to improve the piezoelectric properties of PZT ceramics. Complete perovskite phase is synthesized for PZN content up to 10 mol%. Piezoceramics having dielectric constant higher than 3000 and planar coupling factor about 60% are obtainable. However, these properties seem to be deteriorated by decreasing the thickness of ceramic plate. Plate with thickness smaller than 100μm shows nothing in superior piezoelectric properties. The second phase ZrO2 due to the evaporation of PbO phase during sintering is the dominant factor. This non-piezoelectric phase exists on the surface of piezoceramic plate and gradually plays an important role when thickness is thin enough. Experimental results demonstrate both the control of PbO vapor pressure and the processing conditions can effectively reduce such deterioration.

Polymorphic Phase Transformation of Lead Monoxide and Its Influence on Lead Zirconate Titanate Formation

The polymorphic phase transformation of PbO from massicot to litharge phase is easily produced by mechanical force. The transformation is relatively quick by wet ball‐milling. The additions of TiO2 and ZrO2 tend to retard it. A second‐order exponential relation is observed between the fractional conversion and the milling time for pure PbO, PbO‐TiO2, and PbO‐ZrO2‐TiO2 systems with a rutile constituent. This exponential relation is changed into a first‐order logarithmic relation when anatase instead of rutile is used. Although the PbOss phase is observed irrespective of the phase of the PbO in the raw materials, this PbOss peak is more obvious when massicot PbO or anatase TiO2 is used. The formation of PbOss phase is also dependent on the reactivity of the ZrO2, and its presence can affect the formation and piezoelectric properties of PZT ceramics.

Effect of Porous Structure to Piezoelectric Properties of PZT Ceramics

Porous Pb(Zr0.53 Ti0.47)O3 ceramics with three dimensionally interconnected structure were prepared by modifications of conventional powder sintering methods. The piezoelectric and elastic properties of the porous PZT were investigated by related with pore structures such as porosity and pore size. As porosity increased, permittivity decreased linearly and piezoelectric coefficient d33 increased gradually, so the voltage output coefficient g33 increased. The g33 value was 200–300×10-3 (Vm/N) at the porosity of 0.65.