Piezoelectric Ceramic Materials Research Articles

Evaluation of the dielectric, and piezoelectric properties and optimizing the figure of merit of the 0–3 KNN-0.8ZnO/PVDF-HFP piezoelectric composite by the Taguchi method

Piezoelectric ceramic and composite materials are attractive for various applications, but they can be challenging to process. In this research, KNN-0.8ZnO with high density (ρth=95 %), favorable microstructure, and suitable dielectric and piezoelectric properties (K=875, d33=125 pC/N, tanδ=0.01) was first synthesized. Additionally, polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP) copolymer, known for its advantageous piezoelectric and mechanical properties, was selected as the polymer phase. subsequently, the KNN-0.8ZnO/xPVDF-HFP composite samples with a 0–3 connectivity pattern were made with the cold sintering method. The Taguchi design of experiment (DOE) was employed to determine the optimal condition for maximizing the figure of merit (FOM). Furthermore, an analysis of variance (ANOVA) was carried out to evaluate the significance of individual factors on each measured property. Phase identification was performed using X-ray diffraction (XRD) analysis, while the microstructure was examined using scanning electron microscopy. Among the different composite samples fabricated using the L9 orthogonal array (OA) of the Taguchi method, the KNN-0.8ZnO/20PVDF-HFP composite containing 20 wt% polymer phase, that was cold-sintered under a pressure of 400 MPa at 200 ͦC for 2 h, exhibited the highest FOM value of 1.945Pm2/N. This result aligns with the optimal conditions predeicated by the Taguchi DOE method. The compressive strength of the KNN-0.8ZnO/20PVDF-HFP composite was assessed through a compression test, yielding a value of 207 MPa, while the elastic modulus was approximately 3 GPa. The findings of this study demonstrate that the cold sintering method is an effective approach for producing dense piezoelectric composites with favorable electrical and mechanical properties, along with a high FOM for energy harvesting applications.

Development of a high-power testing system for piezoelectric ceramic material

Abstract Traditionally, the testing of piezoelectric material loss occurs under low-power conditions, limiting the accurate assessment of the high-power mechanical quality factor. To address this limitation, this study proposes a high-power testing method and device for evaluating the performance of piezoelectric ceramics in practical applications. This method involves determining the resonant frequency of the sample and applying that specific frequency to drive it. The laser doppler vibrometer collects the displacement signal of the sample vibration. Subsequently, the oscilloscope records the current signal, and the data is analyzed using a terminal device to assess the high-power characteristics of the sample. To simulate a high vibration speed working environment, an applied voltage induces vibration on the sample’s surface until the maximum vibration speed is reached, at which point it is short-circuited. This method is capable of analyzing the high-power characteristics of piezoelectric ceramic materials, facilitating a further assessment of the variation of their mechanical quality factor under high-power conditions as a function of vibration velocity.

Research progress in the study of textured piezoelectric ceramics

Piezoelectric ceramics have the advantages of uniform composition, excellent performance, good electromechanical coupling performance, and high cost performance. They are currently one of the important materials for manufacturing sensors and semiconductor components on the market. Although piezoelectric ceramic materials are widely used because of their many advantages, how to improve their piezoelectric properties is still a hot and difficult research spot. Previously, the piezoelectric properties of piezoelectric ceramics were affected by adjusting the grain size, but due to its limited enhancement effect, researchers hope to find other ways to improve the piezoelectric properties of ceramics more efficiently. Research has found that texture process can enable isotropic ceramics to obtain similar characteristics to single crystals that exhibit anisotropy. This greatly improves the piezoelectric properties of ceramics. During the texture process, the type and content of the template, texture degree and texture orientation, and other factors will significantly affect the piezoelectric properties of textured ceramics. With the continuous development of texture technology and process, the piezoelectric properties of textured ceramics have been significantly improved, but the practical application is less. Based on this, this article expounds the design principles of textured ceramics, summarizes the progress in the preparation of textured piezoelectric ceramics, and systematically explains the importance of template and texture orientation selection in texture processing. Finally, this paper also analyses the application of textured ceramics, and looks forward to the optimization methods and development prospects of piezoelectric ceramics. It is hoped to help the application and development of piezoelectric ceramics.

Spark plasma sintering of sodium bismuth niobate that exhibits superior piezoelectric performance

AbstractHigh‐performance piezoelectric ceramic materials are required for piezoelectric sensors under harsh conditions in nuclear power plants, aeronautics, and aerospace. In this work, a lead‐free high‐Curie‐temperature (TC ∼792°C) Aurivillius‐type sodium bismuth niobate, Na0.5Bi2.5Nb2O9 (NBN), was fabricated through spark plasma sintering (SPS). The textured NBN ceramics with a high orientation factor of 83% exhibit significantly enhanced piezoelectric performance with a piezoelectric constant d33 of 31.2 pC/N, three times higher than that of nontextured NBN (d33 ∼ 11.6 pC/N). More importantly, the textured NBN ceramics maintain excellent electrical properties at high temperature, with a high in situ d33 of 35.9 pC/N, very low dielectric loss tanδ = 2.5% (@ 100 kHz) and high dc electrical resistivity ρ of 7.5 MΩ cm at 500°C. These results suggest that the textured NBN ceramics are good high‐temperature piezoelectric ceramic materials, and have promising applications in the field of high‐temperature piezoelectric sensors.

In situ electric field-dependent structural changes in (Ba,Ca)(Zr,Ti)O3 with varying grain size

The functional properties of piezoelectric ceramic materials, such as barium titanate, are highly dependent on grain size. Lead-free polycrystalline Ba0.85Ca0.15Zr0.1Ti0.9O3 (BCZT) samples were prepared with a combination of the hydrothermal method and spark plasma sintering to achieve grain sizes from 100 nm to 10 μm by varying the maximum sintering temperature. In this range, a transition from a nearly linear dielectric to a ferroelectric response can be seen in macroscopic electromechanical measurements, demonstrating the importance of grain size on functional properties in BCZT. Furthermore, in situ electric field-dependent synchrotron x-ray diffraction measurements were performed to quantify the intrinsic and extrinsic strain contributions and their variations with grain size. At lower grain sizes, the data revealed a significant loss of extrinsic contributions in the piezoelectric behavior, limiting the response to intrinsic contribution associated with lattice strain. For BCZT, a critical grain size between approximately 0.08 and 0.18 μm is proposed, below which no piezoelectric response was observed.

Research and fabrication of bimetallic plate transducer based on finite element analysis

By enhancing the type 1–3 piezoelectric composite material, a highly sensitive hydroacoustic transducer sensitive element structure is suggested for uses in sonar systems, such as small target identification and fine imaging. A lower metal plate, a piezoelectric ceramic column array, and an upper metal plate make up the piezoelectric material structure. The resonance frequency of the bimetal plate type piezoelectric ceramic array material was theoretically analyzed, the sensitive element geometry of the bimetal plate piezoelectric material was studied using finite element simulation, the material choice for the metal plate affected the material’s performance, and the parameters of each size of the sensitive element were determined. These findings served as a guide for the production of a highly sensitive hydroacoustic transducer, as well as the structure of the piezoelectric material transducer in the water performance test. Results indicate that the structure transducer has a maximum transmit voltage response of 178 dB and a −3 dB bandwidth of approximately 25 kHz; the transducer may be efficiently tuned for a maximum receive sensitivity of −172 dB.

Kesan Penggantian Litium ke atas Struktur, Sifat Fizikal dan Sifat Elektrik terhadap Seramik BCZT

The invention of novel lead-free piezoelectric materials with ABO3 perovskite structure, based on barium calcium zirconate titanate (BCZT) for application in various device especially in sensor application. In this work, BCZT with lithium substitution at the calcium site with composition Ba0.85Ca0.15-xLi2xZr0.1Ti0.9O3 (x = 0.00, 0.03, 0.06, 0.09 and 0.12) were synthesized by using the conventional, solid state reaction method. The influence of different Li content on the structure, microstructure, density, and electrical properties were investigated. The results show that substitution led to the improvement of the physical and electrical properties of the piezoelectric ceramic materials. The physical properties show the largest grain size and the highest value of density, ρ which is 4.158 g/cm3 for x = 0.06. This physical properties led to the highest value of piezoelectric coefficient, d33, remnant polarisation, Pr and saturated polarization, Ps which are 304.6 pC/N, 3.27 µC/cm2, and 5.54 µC/cm2, respectively, while the highest dielectric constant, ɛr was 3994 when x = 0.12.

A self-powered wireless sweat-analysis patch for real-time monitoring physiological status

For both professional and amateur athletes, perspiration analysis technique is considered as a powerful tool for real-time monitoring the athletes’ physiological status during sports. This study presents an innovative self-powered wireless sweat-analysis patch worn on the skin for real-time monitoring chloride concentration and pH levels in perspiration. The patch consists of two main components: self-powered unit and sensing unit. The power unit, made of piezoelectric ceramic materials, converts mechanical energy during exercise into electrical energy to drive the whole system. The sensing unit has the functions of sampling and analyzing the sweat, and wireless communication. Through an exactly designed hydrophobic and hydrophilic composite microchannel structure, sweat is effectively guided to the storage chamber. The colorimetric fabrics embedded in the chamber respond to the presence of chloride ions and pH levels in the sweat, producing a color-changing reaction. Color sensors above the fabrics detects these color changes for analyzing the sweat, while Near Field Communication (NFC) technology wirelessly transmits this information to outside mobile devices or data-collection cloud. This system not only provides a new avenue for real-time monitoring of athletes’ health status but also offers a scientific basis for adjusting training plans.

Polymeric Macro‐Molecular Piezoelectric Sensors for Evaluation of Structural Damage

AbstractFinding damages and their prevalence in structures is a very challenging problem. In order to identify potential structural damage, non‐destructive methods are not very helpful. One of the most popular piezoelectric ceramic materials used worldwide is macromolecular lead zirconate titanate (PZT), also known as Pb[Zr(x)Ti(1‐x)]O3. PZT transducers are proving to be a successful alternative for assessing the structure's health. The Macro‐molecular PZT's self‐actuating and sensing properties are utilized by the electromechanical impedance (EMI) method. In this capacity, the macro‐molecular PZT patches serve as co‐located actuators and sensors and make use of ultrasonic vibrations to produce a distinctive admittance “signature” of the structure. PZT patches perform exceptionally well in terms of damage sensitivity. The higher modes of vibration are locally activated by the local application of an AC source on the PZT transducers attached to the host structure. The alteration of the admittance response is a sign of injury to the transducer's vicinity. In the current study, the damage percentage and its location in a 150 × 150 × 150 mm concrete cube are being examined. Regression analysis is also used to determine the concrete cube's strength. This method also can identify hair‐like cracks at an early stage, which explains how it can shield the building from serious failures.

Giant piezoelectric response and structure evolution of Bi0.5(Na0.3K0.3Li(0.4-x)Bax)0.5ZrO3 modified (K0.48Na0.52)(Nb0.95Sb0.05)O3 lead-free piezoelectric ceramics

The composition of materials can significantly affect the structure and properties of KNN based piezoelectric ceramics. Here, 0.965(K0.48Na0.52)(Nb0.95Sb0.05)O3-0.035Bi0.5(Na0.3K0.3Li(0.4-x)Bax)0.5ZrO3 ceramics were designed and synthesized using CuO as a sintering aid to promote densification of ceramics. The results show that these ceramics had orthorhombic-tetragonal phase transition structure, and the ratio of the two phases becomes an important factor affecting the electrical properties. When the ratio of the two is close, the piezoelectric performance is optimized. Under specific composition, the sample exhibits a large piezoelectric effect, with the piezoelectric constant and inverse piezoelectric constant reaching 347 pC/N and 1052 p.m./V, respectively. These results prove that rational composition and structure modulation can effectively improve the performance of KNN-based lead-free piezoelectric ceramics, making it a promising alternative for lead-based piezoelectric ceramic materials.

Regulation of domain wall motion in PZT-based ceramics through the introduction of local stress fields

At present, a big challenge exists yet in the piezoelectric ceramic material that high piezoelectric performance and low losses (large Qm and low tanδ) are difficult to achieve concurrently due to the effects of domain switching and domain wall motion on electromechanical properties. In this work, by introducing secondary-phase particles (SnO2 particles) into the hard PZT matrix, we successfully build local stress fields in the ceramic. These local stress fields not only pin the domain and domain wall but also diminish the domain size and increase the domain wall density. The former is in favor of reducing the losses, while the latter is beneficial to promoting the piezoelectric properties. Thus, the optimized piezoelectric properties and losses in the ceramic can be obtained simultaneously. The results show that in the PZT/0.3 wt%SnO2 composite, the mechanical quality factor reaches 2800 and the dielectric loss is only 0.4 %, which are superior to the hard PZT matrix. Meanwhile, the composite ceramic has a high piezoelectric constant of 390 pC/N. These excellent properties will push the development of next-generation high-power electromechanical devices.

Review on PZT as a mechanical engineering material

Having the distinction of being one of the most extensively employed piezoelectric ceramic materials worldwide and multi-faceted, lead zirconate titanate (PZT) has numerous applications and characteristics. In 1954, a remarkable discovery happened at the Tokyo Institute of Technology, which was the development of PZT. Due to its excellent dielectric constant, piezoelectric value, polarization, high Curie temperature, and flexibility, it has been widely used in the field of mechanical engineering, along with other branches of sciences. The main interest of this review article is to describe the significance and involvement of PZT in the field of mechanical engineering. This article starts with a brief review of the history of PZT, after that different synthesis methods, and applications of PZT in relevance to the field of mechanical engineering have been discussed. Finally, this article concludes with the future scope of PZT in the field of mechanical engineering.

Design ultrasonic power generators for welding machines using piezoelectric ceramic materials for welding on non-woven fabrics

This paper presents the design and manufacture of ultrasonic emitters for welding machines using piezoelectric ceramic materials for welding on non-woven fabrics. The ultrasonic vibrating membrane (UVB) used for the transducer is investigated to ensure that there are no cracks in the material structure. These parameters serve as the basis for evaluating the quality of the ultrasonic vibrating membrane in the fabrication of an oscillator for ultrasonic transducer welding (USTW). The ultrasonic power generator (USPG) is made of high-frequency components and power components to supply electrical oscillations to the UVB. This vibrating source must be compatible with the USTW to operate at maximum efficiency. Due to the influence of the manufacturing process and USTW usage environment, after operating for a long time, the resonant frequency (fr) will be changed. Therefore, the USPG needs to monitor the frequency of the USTW automatically. Matching the impedance of USTW and USPG is very important to get the most out of USPG power. The fabrication results show that the use of high-resolution timer to generate the control frequency for USPG achieves high accuracy, with the largest error of 0.006% at 18401.12 Hz when surveyed in the range of 18 to 22 kHz. The parameters of control signal delay between two phases and pulse width also give very good results. Impedance-matching (IM) networks also show good exploitation of USPG when compared to USPG without IM.

Formulation and rheological characterization of piezoelectric nanofluids

We introduced a novel concept on energy harvesting nanofluids of hybrid piezoelectric ceramic and polymeric (BaTiO3 and PVdF) materials in PDMS. Rheology, rheo-microscope and impedance spectroscopy complementary enabled the elucidation of the development of microstructure and probing the flow-induced structural transitions. Percolated CNTs enhanced the network mechanically and electrically and improved the output voltage (OV). Traces of PVdF further increased the OV to ca. 7.5 V in their hybrid suspensions.

Friction-induced vibration energy harvesting via a piezoelectric cantilever vibration energy collector

A piezoelectric cantilever vibration energy collector (PCVEC) was developed to harvest friction-induced vibration (FIV) energy. Tests were conducted using a CETR machine. A finite element model (FEM) and a 5-degree-of-freedom (5-DOF) numerical model were established to verify the harvester’s effectiveness. The results show that PCVEC effectively converts FIV energy into electrical energy. PCVEC does not generate any voltage when the block moves in the direction opposite to the friction direction. PCVEC exhibits better deformation capability when the mass and stiffness of cantilever beam are low, enabling the piezoelectric ceramic material to convert FIV energy into electrical energy more efficiently. As the mass and stiffness increase, the deformation capability of the PCVEC weakens, resulting in a decrease in the output voltage.

Design of an Autonomous IoT Node Powered by a Perovskite-Based Wave Energy Converter

Abstract This paper presents the results of experimental research focused on wave energy harvesting and its conversion to power Internet of Things (IoT) devices. The harvesting and conversion process was performed using a wave energy converter (WEC) consisting of a lead zirconate titanate piezoelectric ceramic perovskite material and a prototype power electronic circuit. The designed WEC was considered as a power supply for an end node device (END) of an IoT network. The END consisted of a long-range radio module and an electronic paper display. A set of physical experiments were carried out, and the results confirmed that an energy surplus was supplied by WEC compared to the energy consumed by the END. Hence, the proposed scheme was experimentally validated as a convenient solution that could enable the autonomous operation of an IoT device. The use case presented here for the proposed WEC was analysed for selected sea areas on the basis of wave statistics. The novelty of this paper arises from an investigation that confirms that WECs can significantly contribute to the development of wireless and mobile IoT communication powered by freely available sea wave energy.

SH-wave scattering by the interface crack of piezoelectric ceramic polymer composites

The scattering of SH waves by interfacial crack in piezoelectric ceramic polymer composites is investigated. The mixed boundary condition are reduced to dual integral equations using Fourier transforms, and the series and Schmidt methods are used to solve an unknown quantity in crack displacement, and the expression of stress intensity factor at crack tip is obtained. The method was verified by degrading the piezoelectric ceramic polymer to the piezoelectric ceramic material. Finally, the crack propagation under different conditions such as frequency and angle are analyzed, as well as the influence of different piezoelectric ceramic polymer materials on crack propagation. It is of great significance for fracture propagation. This method can also be used as a guide for SH wave scattering of different interface cracks in real life, such as multi-cracks, rectangular crack and penny-shaped crack, so it can also be used as a starting point for future research.

Design and simulation of micro piezoelectric fiber triaxial acceleration sensor

Aiming at the demand for passive sonar systems for medium and low-frequency detection, low cost, and small working platform working sensor, a three-axis pressure piezoelectric accelerometer based on piezoelectric ceramic fiber is designed. Firstly, based on the acoustic vibration pick-up principle and extended Hamilton, the action mode of the accelerometer is analyzed theoretically to determine the accelerometer structure size. The accelerometer with a special mass structure is designed by using axially polarized piezoelectric ceramic fiber. The characteristic frequency and frequency domain analysis of the accelerometer are simulated by the FEM method. The results show that the overall size of the piezoelectric accelerometer is 20 mm ×20 mm×35 mm, the first-order natural frequency is 410 Hz, the external field directivity is standard “8” type, and the acceleration sensitivity reaches 112.2 mV/g, which verifies the great potential of the three-axis accelerometer designed by piezoelectric ceramic fiber material in the field of medium and low frequency.

Research on a stacked high-sensitivity hydroacoustic transducer

PurposeIsland attack and defense, emergency rescue, scientific research, civilian fisheries and other fields are inseparable from timely, high-quality underwater communications. However light and other electromagnetic waves are severely attenuated in water, acoustic is currently the only energy carrier that can transmit signals over long distances in water. However, the complex water environment and serious interference bring serious challenges to underwater activities using underwater acoustic sensors-hydroacoustic transducers. Thus, this paper aims to develop a class of high reception sensitivity hydroacoustic transducer structures to provide research and utilization ideas for related scholars.Design/methodology/approachThe electromechanical coupling coefficient is improved by converting the thickness vibration mode of the piezoelectric ceramic into the longitudinal vibration mode of the piezoelectric pillars array, and no polymer is added between the piezoelectric pillars array to reduce lateral coupling as well as internal friction, which can thus reduce the energy losses. Radial stacking in parallel can also enhance the charge generated through the positive piezoelectric effect. The optimal parameters of the structure are determined by equivalent circuit method and finite element analysis, and a hydroacoustic transducer of this structure is fabricated finally.FindingsAccording to the standard test procedure, the hydroacoustic transducer was tested in water. The tests show that the conductance curve of the stacked high-sensitivity hydroacoustic transducer tested in the air is in good agreement with the simulation results. The resonant frequency is about 118 kHz, and the receiver sensitivity is −166 dB. The stacked material hydroacoustic transducer is in the high-frequency range and has a much higher sensitivity (−166 dB) than many types of hydroacoustic transducers fabricated by piezoelectric ceramic (less than −200 dB).Research limitations/implicationsAlthough the stacked high-sensitivity hydroacoustic transducer that the authors have fabricated has a performance improvement, it has a limitation. The hollow design of the pillar arrays increases the reception stress on each pillar, and the imposed pressure comes from water also increases simultaneously, so the depth of water that the stacked high-sensitivity hydroacoustic transducer can operate in may be slightly shallower than that made of a pure piezoelectric ceramic block or a piezoelectric ceramic material with polymer added. This will be a problem to be solved in a future deployment.Practical implicationsWhether it is marine scientific research or in various fields such as civil recreation and fishing, hydroacoustic communication and necessary underwater exploration are indispensable for acoustic waves. The hydroacoustic transducer is the sensor that sends and receives sound waves, so a lot of water equipment, such as yachts, sonar buoys, and so on, cannot be separated from the hydroacoustic transducer. In addition, the complexity of the water environment also requires a good performance of the hydroacoustic transducer to facilitate the convenience and effectiveness of subsequent signal processing. Therefore, hydroacoustic transducers have great market and commercial value.Social implicationsHydroacoustic transducers are not only of great commercial value but also have a significant impact on the military as well as on people’s livelihood. As we all know, in the area of submarine communication and underwater exploration, sonar is the main force. The performance of the hydroacoustic transducer directly affects the performance of the hydroacoustic signal processing system, and ultimately directly determines the success or failure of the mission. In addition, the large-scale replacement of hydroacoustic transducers on equipment requires the concerted efforts of a large number of practitioners, such as material scientists, structural scientists, mathematicians and so on. Therefore, the rise of hydroacoustic transducers has given rise to a large number of learning positions as well as employment positions.Originality/valueTo enhance the reception sensitivity of the hydroacoustic transducer, the authors have optimized the existing hydroacoustic transducer materials and structures to propose a stacked sensitive element, which can effectively enhance the electromechanical conversion coefficient of the piezoelectric material. Furthermore, the authors have manufactured a hydroacoustic transducer using the proposed stacked sensitive element. The test results of the hydroacoustic transducer also show that the designed stacked sensitive element is of great help to enhance the reception sensitivity of the hydroacoustic transducer.

Research on monometallic plate piezoelectric ceramic column array broadband high sensitivity transducer

A kind of broadband and highly sensitive underwater acoustic transducer with increased bandwidth and sensitivity is proposed. The effective electromechanical coupling coefficient of the piezoelectric material and the sensitivity of the transducer are improved by using air instead of polymer in the piezoelectric composite and by covering the upper surface of the piezoelectric column array with metal plates. Besides, the operating bandwidth of the transducer is increased through bandwidth superposition. Theoretical analysis is conducted to determine the resonance conditions of the monometallic plate piezoelectric ceramic array material as a sensitive element. With the dimensional parameters of the sensitive component determined by means of finite element simulation, the transducer is designed and produced. According to the test results, the bandwidth of the transducer reaches 60 kHz, the maximum transmit voltage response is 152.1 dB and the receiving sensitivity is −182.5 dB, which is effective in improving both the receiving sensitivity and bandwidth of the transducer.