Multicomponent PZT-type Research Articles

Effect of Chemical Composition on Magnetic and Electrical Properties of Ferroelectromagnetic Ceramic Composites.

In this paper, ferroelectric–ferrimagnetic ceramic composites based on multicomponent PZT-type (PbZr1−xTixO3-type) material and ferrite material with different percentages in composite compositions were obtained and studied. The ferroelectric component of the composite was a perovskite ceramic material with the chemical formula Pb0.97Bi0.02(Zr0.51Ti0.49)0.98(Nb2/3Mn1/3)0.02O3 (P), whereas the magnetic component was nickel-zinc ferrite with the chemical formula Ni0.5Zn0.5Fe2O4 (F). The process of sintering the composite compounds was carried out by the free sintering method. Six ferroelectric-ferrimagnetic ceramic P-F composite compounds were designed and obtained with different percentages of its components, i.e., 90/10 (P90-F10), 85/15 (P85-F15), 80/20 (P80-F20), 60/40 (P60-F40), 40/60 (P40-F60), and 20/80 (P20-F80). X-ray diffraction patterns, microstructural, ferroelectric, dielectric, magnetic properties, and DC electrical conductivity of the composite materials were investigated. In this study, two techniques were used to image the microstructure of P-F composite samples: SB (detection of the signals from the secondary and backscattered electron detectors) and BSE (detection of backscattered electrons), which allowed accurate visualization of the presence and distribution of the magnetic and ferroelectric component in the volume of the composite samples. The studies have shown that at room temperature, the ceramic composite samples exhibit good magnetic and electrical properties. The best set of physical properties and performance of composite compositions have ceramic samples with a dominant phase of ferroelectric component and a small amount of the ferrite component (P90-F10). Such a composition retains the high ferroelectric properties of the ferroelectric component in the composite while also acquiring magnetic properties. These properties can be prospectively used in new types of memory and electromagnetic converters.

The Effect of Mixed Doping on the Microstructure and Electrophysical Parameters of the Multicomponent PZT-Type Ceramics.

This work shows the influence of admixture on the basic properties of the multicomponent PbZr1−xTixO3 (PZT)-type ceramics. It presents the results of four compositions of PZT-type material with the general chemical formula, Pb0.99M0.01((Zr0.49Ti0.51)0.95Mn0.021Sb0.016W0.013)0.9975O3, where, in the M position, a donor admixture was introduced, i.e., samarium (Sm3+), gadolinium (Gd3+), dysprosium (Dy3+) or lanthanum (La3+). The compositions of the PZT-type ceramics were obtained through the classic ceramic method, as a result of the synthesis of simple oxides. The X-ray diffraction (XRD) pattern studies showed that the obtained multicomponent PZT materials have a tetragonal structure with a P4mm point group. The microstructure of the obtained compositions is characterized by a well crystallized grain, with clearly visible grain boundaries. The composition with the admixture of lanthanum has the highest uniformity of fine grain microstructure, which positively affects its final dielectric and piezoelectric properties. In the multicomponent PZT-type ceramic, materials utilize the mixed (acceptor and donor) doping of the main compound. This dopiong method has a positive effect on the set of the electrophysical parameters of ceramic materials. Donor dopants W6+ (at positions B) and M3+ = Sm3+, Gd3+, Dy3+, and La3+ (at positions A) increase the dielectric and piezoelectric properties, while the acceptor dopant Sb3+ (at positions B) increases the time and temperature stability of the electrophysical parameters. In addition, the suitable selection of the set of admixtures improved the sinterability of the ceramic samples, as well as resulted in obtaining the required material with good piezoelectric parameters for the poling process. This research confirms that all ceramic compositions have a set of parameters suitable for applications in micromechatronics, for example, as actuators, piezoelectric transducers, and precision microswitches.

Multi-component PZT ceramics obtained by mechanochemical activation and conventional ceramic technology

In the paper, the multi-component PZT-type ceramics doped with Mn4+, Sb3+, W6+ and Ni2+ were investigated. The following chemical composition was selected: Pb(Zr0.49Ti0.51)0.94Mn0.01Sb0.03W0.015Ni0.01O3. The ceramic powders were synthesized by two methods: (i) the classical technological method using powder calcination and (ii) mechanochemical synthesis at room temperature. Densification of the powders (sintering) was carried by free sintering method. In the case of the mechanochemical activation, the development of the synthesis has been monitored by XRD and SEM investigations after different milling periods (25 h, 50 h and 75 h). From the obtained powder, the bulk ceramic samples have been prepared by uniaxial pressing and subsequent sintering. The ceramic multi-component PZT-type samples were characterized in wide temperature range by DTA, TG, DC electrical conductivity, XRD, SEM and EDS (energy-dispersive spectrometry) methods, and their ferroelectric, dielectric and piezoelectric properties were studied. At the work, a comparison of test results for samples obtained by two methods was made. The X-ray investigations confirmed that the obtained material exhibits a perovskite-like structure with a tetragonal phase (close to the morphotropic area). The detailed results of the multi-component PZT-type ceramics predispose these materials in microelectronic applications, for example, as element of the actuators and piezoelectric transducers. The application of the mechanochemical synthesis to obtain the PZT-type materials allows to shorten the time of the technological process, and at the same time not to reduce the electrophysical properties of ceramic samples.

Comparison of Electrophysical Properties of PZT-Type Ceramics Obtained by Conventional and Mechanochemical Methods.

In the paper, the multicomponent PZT-type ceramics with Pb(Zr0.49Ti0.51)0.94Mn0.015Sb0.01W0.015Ni0.03O3 composition have been obtained by conventional and mechanochemical methods. With conventional ceramic technology, PZT-type ceramics have been synthesized by the method of calcination powder (850 °C/4 h). Instead of this step, the mechanochemical synthesis process for different milling periods (15 h, 25 h, 50 h, 75 h) has been applied for a second batch of samples. To obtain the dense PZT-type ceramic samples, powders have been sintered by free sintering method at conditions of 1150 °C/2 h. Studies have shown that the perovskite structure of the PZT-type material is formed during mechanochemical activation of powders during the technological process at low temperature. The application of the mechanochemical synthesis to obtain the PZT-type materials also allows shortening of the technological process, and the useful electrophysical properties of ceramic samples are not reduced at the same time. The presented results have confirmed that the investigated materials can be used in microelectronic applications, especially as elements of actuators and piezoelectric transducers.

Electrophysical properties of a multicomponent PZT-type ceramics for actuator applications

A multicomponent lead zirconate titanate (PZT)-type ceramics doped with Mn4+, Sb3+, W6+, and Ni2+ with a perovskite structure was obtained. The designed material had a chemical composition of Pb(Zr0.49Ti0.51)0.94Mn0.014Sb0.02W0.014Ni0.02O3. Ceramic powders were synthesized by the calcination method, and they were densified by the free sintering method. We present the results of electrophysical measurements of the PZT-type ceramics, including scanning electron microscopy microstructure, dielectric, ferroelectric, pyroelectric, and thermally stimulated depolarization currents, piezoelectric properties and DC electrical conductivity. The results obtained for the multicomponent ceramics predispose it to micromechatronic applications as part of actuators.

Microstructure and physical properties of the multicomponent PZT-type ceramics doped by calcium, sodium, bismuth and cadmium

In this work, the multicomponent Pb(Zr0.58Ti0.42)O3 ceramics doped by calcium (Ca), sodium (Na), bismuth (Bi) and cadmium (Cd) was designed and obtained by the hot uniaxial pressing method. Comprehensive electrophysical properties including crystalline structure, microstructure, dielectric, electromechanical and piezoelectric of the ceramics were made. The Pb0.92Ca0.02Na0.01Bi0.05(Zr0.58Ti0.42)0.98Cd0.02O3 ceramics obtained by the hot uniaxial pressing method has a microstructure of a regularly crystallized grain. The multicomponent material shows high values of dielectric and piezoelectric properties with high ferroelectric hardness. A wide and rectangular hysteresis loop of the PZT-type ceramics shows high ferroelectric hardness of obtained ceramics. Studies have also shown that multicomponent PZT-type ceramics exhibits a strong S–E behavior. The S–E electromechanical loops have characteristic “butterfly wings” shape with high values of mechanical strain. These properties of the obtained material allow its application in the modern microelectronics and micromechatronics, for example, in constructing electromechanical and electroacoustic transducers, piezotransformators, piezoelectric motors, etc.

Technology and electrophysical properties of Mn4+, Sb3+, Dy3+ and W6+ -doped Pb(Zr0.49Ti0.51)O3 ceramics

In paper three multicomponent PZT-type ceramics doped by Mn4+, Sb3+, Dy3+, W6+ have been prepared by the conventional mixed oxide method. The multicomponent PZT-type ceramic powders were synthetized by calcining route, while densification was carried out by pressureless sintering method. The paper presents XRD, SEM, EDS, dielectric and DC electric conductivity measurements of the multicomponent PZT-type ceramic samples. Conducted tests indicate obtained multicomponent PZT-type exhibit good dielectric properties giving the possibility for their use as actuators and piezoelectric transducers in modern micromechatronic and microelectronic applications.

The Multicomponent PZT-type Ceramics for Micromechatronic Applications

AbstractIn the paper two compositions of the multi-component PZT-type ceramics admixtures by Mn4+, Sb3+, W6+, Ni2+were presented. The ceramic powders were synthesized by the calcination of powders while their densification was carried out by free sintering method. The dielectric, ferroelectric, piezoelectric studies and DC electrical conductivity of the multicomponent PZT-type samples were presented. The results of the multi-component ceramics predispose these type materials in micromechatronic and microelectronic applications for example as element of the actuators.

Ferroelectromagnetic solid solutions on the base piezoelectric ceramic materials for components of micromechatronics

In the presented work, a ferroelectromagnetic solid solutions based on PZT and ferrite powders have been obtained. The main aim of combination of ferroelectric and magnetic powders was to obtain material showing both electric and magnetic properties. Ferroelectric ceramic powder (in amount of 90%) was based on the doped PZT type solid solution while magnetic component was nickel–zinc ferrite Ni1−xZnxFe2O4 (in amount of 10%). The synthesis of components of ferroelectromagnetic solid solutions was performed using the solid phase sintering. Final densification of synthesized powder has been done using free sintering. The aim of the work was to obtain and examine in the first multicomponent PZT type ceramics admixed with chromium with the following chemical composition Pb0.94Sr0.06(Zr0.46Ti0.54)O3+0.25at% Cr2O3 and next ferroelectromagnetic solid solution based on a PZT type ferroelectric powder (Pb0.94Sr0.06(Zr0.46Ti0.54)O3+0.25at% Cr2O3) and nickel–zinc ferrite (Ni0.64Zn0.36Fe2O4), from the point of view of their mechanical and electric properties, such as: electric permittivity, ε; dielectric loss, tanδ; mechanical losses, Q−1; and Young modulus, E.

Ferroelectric Properties and Internal Friction in Doped PZT Ceramics

Multicomponent PZT-type solid solution with composition: Pb0.975Ba0.01Ca0.01Sr0.005 (Zr0.52Ti0.48)O3+1.4wt.%Bi2O3+0.3wt.%GeO obtained by hot uniaxial pressing method is described in this paper. There are presented the results of studies of structural, dielectric and internal friction of obtained multicomponent PZT-type ceramics. It has been stated that the dielectric anomalies and internal friction anomalies are observed in similar temperature ranges. Obtained PZT-type ceramics have high value of the dielectric permittivity and low dielectric losses. The high temperature of phase transition and high value of electric permittivity allow considering this material as a base for low frequency and high temperature electromechanical transducers.

Ferroelectric-Ferromagnetic Solid Solutions of PZT-Ferrite Type

In presented work the ferroelectric-ferromagnetic solid solutions based on multicomponent PZT type ferroelectric powders and ferromagnetic powder (chromium-manganese-zinc ferrite) were designed and obtained. In solid solutions the ferroelectric powders have 90 percent share, while ferrite powders have 10 percent share. The syntheses of mixed components of solid solutions were performed using the solid phase method and final densification was performed by free sintering (compacting method).The XRD, the microstructure, dielectric and magnetic (and electrical hysteresis loop) investigations were performed. Obtained results shown that solid solution PZT-ferrite type shown at low temperatures coexistence the magnetic and the electrical subsystem. Such properties of these materials give the possibility to use them to construct magnetoelectric transducers.

The optimization of the properties of the multicomponent PZT type ceramics by the choice of appropriate technological conditions

By the conventional ceramic sintering method, doped lead zirconate titanate (PZT) samples with the chemical composition 0.55PbTiO 3 -0.43PbZrO 3 -0.02[Pb(Cd 0,5 W 0,5 )O 3 ] have been obtained from oxides PbO, ZrO 2 , TiO2, CdO, WO 3 . For the samples of A series, synthesis was led in the 1223 K temperature by 3 hours and in the case of the samples of B series, by 6 hours in the same temperature but in two parts (each 3 hours long). Both series were sintered in the 1423 K temperature by 6 hours. All samples were subjected to polarization (T pol . = 423 K, E pol . = 30kV/cm, t pol . = 30min.) and next dielectric (e T 33 /e 0 , tgδ) properties were measured for the samples in the shape of discs. For the samples of B series, larger values of the dielectric permittivity e T 33 /e 0 were observed, as well as lower values of the dielectric loss tgδ.