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A transducer is any device used to convert energy from one form to another, such as a conversion from mechanical to electrical energy or vice versa. An electroacoustic transducer is a device that converts acoustic energy (sound) into electrical energy (voltage or current) or vice versa.
Piezoelectric materials modify their dimensions when an electrical field is applied (inverse piezo effect) and generate an electrical charge when a force is applied (direct piezo effect). In other words, they transform mechanical power into electrical power and vice versa, and this the reason why they are frequently referred to as transducers.
The piezoelectric effect is used in many applications that involve the production and detection of sound, electronic frequency generation. The inverse piezo effect lends itself particularly for precise and fast motion generation, while the direct piezo effect can be used for sensor applications.
A piezoelectric transducer (also known as a piezoelectric sensor) is a device that uses the piezoelectric effect to measure changes in acceleration, pressure, strain, temperature or force by converting this energy into an electrical charge. An early application of piezo transducer technology occurred during World War I with the use of sonar, which used echoes to detect the presence of enemy ships. Small piezo transducers were also mostly present in landline phones. They sat inside the ringer and helped to generate a noticeable noise to alert people to incoming calls. In addtion, piezoelectricity finds a home inside quartz watches as well, which is what keeps them so precise.
It acts as an ignition source for cigarette lighter and used in sonar, microphone, force, pressure and displacement measurement. When the transducer is used to generate sound, it is called a projector, transmitter, or source. When it is used to detect sound, it is called a receiver. Furthermore, when the receiver is employed underwater, it is referred to as a hydrophone.
Piezoelectric transducers
Piezoelectric transducers have several advantages over other methods. Due to their materials’ ability to produce voltage while under the influence of some energy, piezo transducer circuits are Self-generating, they do not require an external power source. Piezoelectric transducer circuits are acessible due to their small dimensions and large measuring range, are easy to handle, install and use.
They have High-frequency response, A much higher-than-normal frequency response means the parameters of these transducers shift quickly. Their incredibly fast response — in the range of microseconds and lower — allow them to be of use in a wide range of applications, even including the generation of ultrasound, with frequencies all the way up to 20 MHz.They are flexible, due to how most of the materials used in construction can be shaped into different shapes and sizes, you can apply these transducers in various fields.
Piezoelectric transducers also have their limitations. While they might be self-generating, they produce Small electric charge hence require a high impedance cable to establish a connection with an electrical interface. Piezo transducers cannot measure output in the static condition, and temperature and humidity variations can affect output. While some materials produce output rates that are relatively higher than their counterparts, output is still low in most respects. You’ll need to attach it to an external circuit.
The piezoelectric transducers are device that have complex impedance. Piezoelectric transmitters produce the maximum mechanical distortion when it is applied with voltage at the resonance frequency. At this point, voltage drops across the transducer is the lowest which allow the highest current feed through the sensor. On the other hand, piezoelectric receivers produce highest electric charge when receive vibration at resonance frequency.
Underwater Applications
Sonar systems use sound propagation to navigate, communicate with or detect objects on or under the surface of the water, such as fish or other vessels. An underwater sonar system consists of projectors, hydrophones, and associated electronics such as amplifiers and data acquisition systems.
Sound Navigation and Ranging or SONAR is a technique to transmit and receive information using sound propagation. Besides that, sonar can be used in navigation, communication between underwater vehicles and detected the object under the surface of water. ROV or UAV will be equipped with sonar transducer to recognize the underwater object. The information from the sonar transducer will build into images using some techniques of signal processing. It is called underwater imaging. The sharp and clear image can be obtained from high resolution and good receiving signal. Thus, the sonar is equipped with an acoustic transducer that has a capability of high sensitivity and high bandwidth.
Piezos are used in sonars for underwater communication, where you benefit from the acoustic waves radiating from the sonar. Transducers for underwater communication devices are usually fitted with piezo components of various shapes manufactured of soft piezoelectric materials. However, for high-power applications, electrically hard materials should also be considered. Sizes depend on the application. The multilayer piezoelectric element used as a transmitter could significantly reduce the level of the driving voltage.
Piezos are used in transducers for underwater imaging systems. Their purpose is to measure and describe targets in the water and on the bottom. Underwater imaging is the most complex type of sonar, where the returning echoes of the sound waves are displayed in detailed 2D or 3D mapping. The varieties of piezoelectric transducers go from simple single transducer up to sophisticated multi-element phased arrays of transducers.
Piezoelectric energy harvesting
Piezoelectric materials take advantage of the small voltages generated by tiny mechanical displacement, vibration, bending or stretching to power miniaturised devices. Harvesting the energies available in the ambient environment such as mechanical vibrations, heat, fluid flows, electromagnetic radiation in the form of light and radio waves (RF), and in vivo energies can supply clean power to operate various electronic devices such as wireless sensor networks, mobile electronics, wearable and implantable biomedical devices.
Various energy harvesting strategies have been proposed using electromagnetic, electrostatic, piezoelectric, triboelectric, thermoelectric, and pyroelectric transduction mechanisms at meso, micro, and nanoscale. Among them, piezoelectric harvesters employ active materials to convert mechanical strains into electric power, whereas electrostatic, triboelectric, and electromagnetic harvesters generate electric power through varying capacitance, frictional contact and electrostatic induction, and magnetic induction, respectively.
Piezoelectric energy harvesting is a very convenient mechanism for capturing ambient mechanical energy and converting it into electric power since the piezoelectric effect is solely based on the intrinsic polarization of the material and it does not require a separate voltage source, magnetic field, or contact with another material as in the case of electrostatic, electromagnetic, and triboelectric energy harvesting, respectively.
Piezoelectric generators are durable, reliable, more sensitive to minute strains, and exhibit 3–5-fold higher density power output and higher voltage output compared to the other energy harvesting methods. Moreover, piezoelectric generators can be manufactured in small dimensions and compact structures, and easily integrated into microelectromechanical systems. Further, they are not affected by environmental factors such as humidity. Thus, piezoelectric transduction is the most promising ambient energy harvesting technology that has found applications in many diverse fields including structures, transportation, wireless electronics, microelectromechanical systems, Internet of Things (IoT), wearable and implantable biomedical devices, and so on
Piezoelectric materials
The piezoelectric effect was discovered by brothers Pierre and Jacques Curie in 1880, and named after the Greek word piezein, that means to press or squeeze. They found that certain crystals were able to generate an electrical charge when mechanically loaded with tension or pressure. If exposed to an electric field, the same crystals would undergo a controlled deformation known as the inverse piezoelectric effect. The rate of charge produced will be proportional to the rate of change of mechanical stress applied to it. Higher will be stress higher will be voltage.
Compression and tension generate voltages of opposite polarity, so when compressed, the piezoelectric material decreases in volume and will have a voltage that has the same polarity as the material. When subjected to tension, the material will increase in volume and its voltage will be opposite to the polarity of the material.
Nowadays, piezoelectric transducers can employ a vast set of piezoelectric materials such as single crystals, ceramics, polymers, biopolymers, macro fiber composites, ferroelectrets, flexoelectric materials and some others.
While many materials can show the piezoelectric effect, the best ones must also possess at least a few of the most desirable qualities. Such characteristics include consistent stability, high output, malleability and resistance to extreme temperatures and humidity. That said, no known material exhibits all of those qualities simultaneously.
There are two types of material – crystals and ceramics. Most crystals occur naturally, while piezoelectric ceramics are manmade. Naturally occurring piezoelectric crystals include:
- Quartz, the second-most common mineral in the Earth’s crust after feldspar.The quartz crystal has the unique property of generating electrical polarity when mechanical stress applied on it along a certain plane. Quartz offers superior stability and slow measuring at varying parameters due to low leakage rates, which means it can provide excellent accuracy — hence why watches most often use them. While they’re still in widespread use, quartz also yields a rather low output, meaning it can’t keep up adequately with demands of more sophisticated technology.
- Berlinite, a rare transparent high-temperature mineral that has the same crystal structure as quartz.
Topaz, a gemstone that forms in numerous colors. - Tourmaline, classified as a semi-precious stone.
- Cane sugar used to manufacture granulated sugar.
- Rochelle salt, made from two of the first materials found to be piezoelectric: potassium sodium tartrate and monopotassium phosphate. Another material that works incredibly well in transducers is Rochelle salt, which is a synthetic crystal. Of every medium that shows signs of the piezoelectric effect, Rochelle salt produces the highest output of any other material discovered thus far. However, it does have its drawbacks, which can hold back its success in certain environments. These synthetic crystals cannot come into contact with any moisture, nor can they be used at a temperature above 115 degrees Fahrenheit.
In the early 1950s, quartz crystals began to give way to piezoelectric ceramic as the primary transducer material. The advantages offered by a ceramic transducer when compared to other materials include ceramic’s ability to be manufactured in a wide variety of shapes and sizes, its capability of operating efficiently at low voltage, and its ability to function at temperatures up to 300 degrees Celsius. Due to the ability to produce a ceramic transducer in numerous sizes and shapes, ceramic transducers can be easily adapted to a wide variety of industrial applications.
However, the larger coupling coefficients of Rochelle salt and dihydrogen phosphates proved to be more attractive for acoustic devices. In the early sonar systems both quartz and Rochelle salt were used. Quartz had better mechanical properties, which was advantageous in the fabrication process. On the other hand, Rochelle salt had better piezoelectric response. The single crystal or ceramic piezoelectric transducers are very efficient in the ultrasound generation in water, which is caused by the comparable magnitudes of their specific acoustic impedance.
A breakthrough in the construction of electromechanical and electroacoustic transducers was the discovery of ferroelectric-ferroelastic solid solution of lead zirconate titanate (PZT). Perovskite lead zirconate titanate, a polycrystalline monolithic piezoelectric ceramic known as PZT belongs to the same family of materials as barium titanate. The greatest advantage of PTZ is that it can be prepared in the form of a ceramic sample. Such a feature greatly simplifies the sample preparation and greatly reduces the price of the transducers.
Piezoelectric ceramics, or piezoceramics, have found widespread use in sensors and actuators due to their direct coupling which enables operation without bias voltages, and their ability to output large voltages on the order of 50 V to 100 V (although currents are typically quite small, in the nanoamp to milliamp range).
Their piezoelectric response can be controlled by doping. PZT is often doped with niobium or lanthanum to form soft and hard piezoelectric materials, respectively. Niobium-doped PZT (so-called soft-PZT) have increased piezoelectric response. Thus, the large actuator displacement can be achieved at moderate electric fields. Irondoped (hard-PZT) is characterized by smaller hysteresis in the piezoelectric response. The values of piezoelectric coefficients in PZT are several times larger than those in barium titanate.
PZT is a smart material that can be used as a multifunction integrated film for both sensors and actuators. It is widely used in memory cells of logic circuits. In missile applications that require the use of guidance and control systems, it can act as a backup inertial measurement unit (IMU). PZT is also gaining attention in the field of power MEMS for applications in energy storage and power reclamation. Insertion of smart material MEMS sensors into projectiles will provide the methodology required to develop more precise and lethal projectiles for future combat systems.
Unfortunately, the presence of lead in the compound makes PZT the subject of Restriction of Hazardous Substances Directive 2002/95/EC adopted by the European Unionand, therefore, the development of new compositions is a large and ongoing research thrust. Leadfree piezoelectric materials consist of three main compositional families including titanate-based, alkaline niobate perovskitebased, and bismuth perovskite-based materials.
The applicability of PZT is limited by the following reasons. PZT transducers are extremely brittle and they require special attention during handling and bonding procedures. They can easily crack when exposed to large mechanical stresses or deformations. In addition, their conformability to curved surfaces is extremely poor.
Furthermore, in order to provide compliant piezoelectric materials, piezoelectric polymers have been developed, which include polyvinylidene fluoride (PVDF), another common piezoelectric material. While piezoelectric polymers are lightweight and flexible, their coupling is considerably lower than their ceramic counterparts. Recently, Harstad et al in 2017 developed a new approach to improve the coupling of PVDF polymers by increasing the β phase percentage in the material composition (note, the coupling coefficient of PVDF materials is directly proportional to the β phase percentage).
Another limitation in the application of PZTs is the limited working temperature of these materials due to phase instability and depolarization in high-temperature applications, such as advanced energy generation systems and turbine engines. Despite tremendous development in high-temperature piezoelectric materials capable of working at temperatures up to 1000 °C in different bulk and thin film formations, the electromechanical coupling properties of the majority of these materials are relatively lower than conventional PZT ceramics. A 0–3-type composite was developed by Qaiser et al in 2018 with embedded BiFeO3 (BFO) grains in the Bi3TaTiO9 (BTTO) matrix to combine the acceptable piezoelectric coefficient of BFO and the high-temperature resistance of BTTO.
Therefore, the concept of active piezoceramic composite transducers (PCT) containing PZT and some flexible adhesive to eliminate the aforementioned drawbacks has been developed. A typical PCT is made of an active layer sandwiched between two thin soft encapsulating layers. The first generation of PCT actuators were manufactured as a layer of cylindrical piezoceramic fibers embedded in a protective polymer matrix material. They were called Active Fiber Composite (AFC). Strain energy density was improved by utilizing interdigital electrodes (IDEs) to produce electrical fields in the plane of the actuator. In order to increase the contact area of the PZT fiber with the electrodes, a new type of PCT actuators with PZT fibers with rectangular cross-section (called Macro Fiber Composite (MFC) actuators) was developed at NASA Langley Research Center.
Piezoelectrets represent a very promising group of piezoelectric substances with electromechanical responses comparable to PZT. Today, piezoelectrets are made of porous polymer films prepared by double-expansion process and corona poling, which introduces immobile free charge carriers on the surface of the voids inside the polymer matrix made of polypropylene. The charges on the surface of the voids form a texture of electric dipoles, so that the piezoelectret has a nonzero macroscopic polarization, which is sensitive to the applied uniform electric field. This makes the piezoelectret extremely flexible, lightweight, with a low acoustic impedance. In addition, piezoelectrets can be produced inexpensively and are environmentally friendly. These properties of piezoelectrets allow the construction of light, flat, and sensitive electroacoutic transducers.
Breakthrough in polycrystalline piezoelectric technology as team achieves the highest efficiency
A team of researchers from Indian Institute of Science, Bengaluru, Université Paris-Saclay, Gif-sur-Yvette, France and Technische Universität München, Germany has provided a material design strategy for polycrystalline piezoelectrics that could achieve electrostrain values larger than 1%. The breakthrough could result in cheaper and efficient piezoelectric actuators.
Single crystal piezoelectric materials, like quartz, Rochelle salt and topaz have been the preferred material for designing piezoelectric devices like actuators and motors. Recently, polycrystalline piezoelectric ceramics have gained the interest of researchers due to their low cost processing and accuracy in controlling the conversion. Polycrystalline piezoelectric materials, however, have never been able to produce electrostrain values-which is a measure of the degree to which the materials deforms for a given value of the applied electric field, of larger than 1%.
In their breakthrough study, the researchers have reported a novel material design strategy which allows them to achieve an electrostrain value of close to 1.3%. They have exploited the efficient switching of ferroelectric to ferroelastic domain of a material by an electric field, to achieve the higher electrostrain value. They have proposed using a pseudo-ternary ferroelectric alloy system, made of Bismuth Ferrite (BiFeO3), Lead Titanate (PbTiO3), and a Perovskite(LaFeO3). Their study has revealed that the larger electrostrain is a result of several factors, including a large spontaneous lattice strain and domain miniaturization. The researchers believe this breakthrough could be utilized to build highly efficient polycrystalline piezoelectric actuators. Talking about their research, the researchers say “This insight for the design of a new class of polycrystalline piezoceramics with high electrostrains may be useful to develop alternatives to costly single-crystal actuators”
SUSTech Junling Wang’s team makes breakthrough in organic-inorganic hybrid piezoelectric materials
In May 2021, Professor Junling Wang from the Department of Physics at Southern University of Science and Technology (SUSTech), and Professor Hongjin Fan from Nanyang Technological University, were reported to have made important progress in the field of piezoelectric materials. They have synthesized new organic-inorganic hybrid ferroelectric materials, achieving a shear strain of 21.5%, which is two orders of magnitude greater than that in conventional ferroelectric polymers and oxides. The work was published in Nature Materials with the title of “Ferroelastic-switching-driven large shear strain and piezoelectricity in a hybrid ferroelectric”.
Piezoelectric materials are widely used to make transducers, sensors, filters, and other devices that play an important role in various fields, and people have made great efforts to improve their strain response. It is well known that ferroelastic switching can produce large reversible strains, as shown in shape memory alloys and specially designed ferroelectric materials. However, achieving ferroelastic switching in traditional ferroelectric materials at bulk level is very challenging due to the high energy barrier associated with their mechanical stiffness.
It is thus possible that materials with large remanent polarization and low stiffness will produce a large piezoelectric response. However, in reality, it is often found that the polarization of flexible organic materials is low, while that of rigid inorganic materials is high. This phenomenon has steered researchers’ attention to organic-inorganic hybrid piezoelectric materials. The research team prepared (PTMA)CdBr3xCl3(1– x) ferroelectric materials by combining flexible organic molecules with a rigid inorganic material framework, and systematically adjusted their electromechanical properties by bromine (Br) doping.
The work of Professor Junling Wang and his team has opened a new direction for the research of piezoelectric materials. The structural confinement effect makes it possible to deterministically control ferroelastic switching and obtain a super large strain. The principle of bond softening can also guide us to design more organic-inorganic hybrid ferroelectric materials with a high piezoelectric response.
Piezoelectric Single Crystals for Underwater Sonar Transducers
Improved materials have cut the weight of today’s sonar arrays, including the transducer “domes,” hydrophones and sound receivers as well as data transmission and loadbearing cabling. More efficient designs have also reduced the power demands placed on the host platform operating (and deploying in the case of variable depth and towed arrays) the sonar system. These improvements have expanded the numbers of platforms that can mount and operate ASW sonar to smaller ships (corvettes and patrol craft) and even unmanned surface vehicles.
Advantages of PMN-PT or PIN-PMN-PT single crystal over traditional PZT material for sonar applications
CTS PMN-PT and PIN-PMN-PT single crystal piezoelectric materials provide increased sensitivity and wider bandwidth for underwater transducers. Thus, the performance marks of underwater transducers are significantly higher when manufactured with piezoelectric single crystal, compared to underwater transducers with the use of standard PZT. Therefore, CTS piezoelectric single crystals have the potential to provide the performance breakthrough for the next generation of underwater sonar transducers.
Broader Bandwidth
It has been proven consistently by industrial applications, as well as in published research that one of the biggest advantages of utilizing PMN-PT for sonar transducers is the increased bandwidth. Design and performance of sonar transducers can be greatly improved due to the much higher electromechanical coupling coefficients (20% higher, on average, compared to traditional PZT) and higher electromechanical strains provided by PMN-PT, compared to traditional PZT.
Smaller Form Factor
The design of the single crystal transducers is critical for fully utilizing the potential advantages of single crystals. Because of its magnitude higher piezoelectric performance, single crystal piezoelectric crystals allow smaller form factor transducer design by decreasing the number of piezoelectric elements necessary. As a result, this not only provides a simplified design, but also provides weight and power advantages. Also, when packaged correctly, it has been proven that they are as strong to shock tests as traditional PZT materials are.
System-Level Advantages
Single crystal materials not only provide advantages at the transducer level, but also at the system level. Next generation sonar transducers with piezoelectric single crystals can utilize smaller number of components, compared to traditional PZT, while improving the performance greatly. As a result, higher performance can be achieved at lower power consumption levels. Lower power consumption also helps increase the battery life of the overall sonar system upon deployment. Once the sonar system is deployed, increased battery performance not only provides longer active life for the system, but also improves deployment cycles, maintenance time and cost.
CTS white paper reports that smaller form factor transducers can be achieved when PIN-/PMN-PT single crystals are utilized. This is due to the higher piezoelectric performance magnitude of PIN-/PMN-PT single crystals, thereby making it possible to decrease the number of piezoelectric elements necessary. As a result, higher performance can be achieved at lower power consumption levels. Lower power consumption also helps increase the battery life of the overall sonar system upon deployment. Once the sonar system is deployed, increased battery performance not only provides longer active life for the system, but also improves deployment cycles, maintenance time and cost.
TRS proposes to develop an extremely low-frequency sonar projector transducer miniaturized through specific designs that allow incorporation into an array on the large diameter underwater vehicles. Piezoelectric single crystal growth technology based on PMN-PT has advanced the acoustic transduction capabilities and has revolutionized various sonar platforms and TRS will utilize second- and third-generation crystal based on PMN-PT to further these capabilities.
Special orientations made practical with the piezoelectric single crystal materials along with a combination of transduction techniques will enable low frequency sonar capability. Phase II will optimize the transducer developed in Phase I to increase depth capability while maintaining the order of magnitude reduction in frequency relative to size
Piezoelectric Materials Market
The global Piezoelectric Materials market size is expected to gain market growth in the forecast period of 2021 to 2025, with a CAGR of 7.0% in the forecast period of 2021 to 2025 and will expected to reach USD 1474.1 million by 2025, from USD 1125.2 million.
Drivers & Restraints-
Rising Automation in Automotive & Electronic Industries to Boost Growth
Several end-use industries such as electronics and automotive are looking forward to bringing in automation in their manufacturing processes. This has further surged the demand for devices, such as motors, actuators, transducers, and sensors. These devices help in the smooth operation of production lines. They utilize piezoelectric materials to measure various quantities, namely, acoustic intensity, strain, pressure, and acceleration. Therefore, the demand for these materials is expected to grow in the coming years backed by the high dependence of industries on automation.
However, these materials are mainly used in energy conversion and sensing devices. But, when they are subjected to harsh environments, such as heavy stress and high temperature, the results can be severely affected. This factor may hamper the piezoelectric materials market growth in the near future.
Market Segments
Based on end-use industry, the market is segregated into aerospace & defense, consumer goods, IT & telecom, healthcare, automotive, and others. Out of these, the automotive segment held 18.4% piezoelectric materials market share in 2019. This growth is attributable to the usage of these type of materials in braking systems, sensors, fuel injectors, and actuators. Also, tire pressure sensors, airbag sensors, seat belt buzzers, and fuel atomizer require these materials extensively. Such factor
Regional Analysis
In terms of geography, in 2019, Asia Pacific generated USD 905.9 million revenue. This growth is attributable to the expansion of production capacities by companies located in South Korea, India, China, Taiwan, and Japan. These countries are considered to be the major manufacturing hubs for consumer goods and electronics. Besides, the COVID-19 pandemic has caused losses for the electronics manufacturers. Thus, the governments of these countries are offering them incentives and tax rebates to set up new production plants.
North America, on the other hand, is anticipated to showcase good growth on account of the major contribution of the U.S. The country is planning to conduct several space exploration programs. Hence, the sensing objects used in such activities would require piezoelectric materials to achieve remote access to the components of the spacecraft. Europe is set to revive after the severe effects of the coronavirus pandemic. This would mainly occur because of the research and development of automated and driverless cars.
Industry
Some of the Top Manufacturers/ Key Players In Piezoelectric Materials Market are PI Ceramics GmbH (Germany), APC International Ltd. (U.S.), CTS Corporation (U.S.), L3Harris Technologies, Inc. (U.S.), CeramTec (Germany), Arkema (France), Solvay (Belgium), Mad City Labs, Inc. (U.S.), Piezosystem jena GmbH (Germany), Sparkler Ceramics (India), Piezomechanik GmbH (Germany), TDK Corporation (Japan), Murata Manufacturing Co., Ltd. (Japan), Kinetic Ceramics (U.S.), Hong Kong Piezo Co. Ltd. (China), Mide Technology (U.S.), Meggit PLC (UK), Johnson Matthey (UK), Piezo Kinetics Inc. (U.S.), TRS Technologies, Inc. (U.S.)
The market houses numerous companies that are mainly focusing on broadening their production capacity. Some of the others are aiming to adopt the strategies of merger and acquisition and new product launches to strengthen their positions. Below are a couple of the latest industry developments:
April 2020: CTS Corporation unveiled four crystal families to be used in automotive-grade crystal resonators. They are best suited for the usage in aerospace & defense, automotive, medical, and industrial sectors. CTS Corporation is the global leader for high volume single crystal (PMN-PT and PIN-PMN-PT) manufacturing. Utilizing the fully integrated manufacturing facilities in Illinois, United States, CTS can provide high volume, single crystal plates (un-diced, diced composite), discs or rings that can be utilized in underwater sonar applications. CTS single crystal materials are manufactured to high quality standards in a ISO-9001:2008 certified facility.
CTS has collaborated with leading defense contractors to co-develop next-generation single crystal sonar transducers that can overperform current generation sonar transducers that utilize standard PZT material. Among defense contractors that utilize piezoelectric single crystals, CTS has been the supplier of choice due to:
i. High quality and high yield PMN-PT and PIN-PMN-PT materials
ii. Ability to provide unique component shapes (e.g. rings, plates with wedges)
iii. High tolerance manufacturing techniques
iv. Flexibility to provide tighter dielectric range components
v. Support from a team of experienced Ph.D level piezoelectric single crystal scientists and well-diversified process engineers.
July 2019: PI Ceramic GmbH expanded its production facility situated in Thuringia. It would surge the facility’s area to 19,500 sq. meters from 12,000 sq. meters. It would include an additional line for the manufacturing of multilayer piezoelectric materials.
References and Resources also include:
https://www.ctscorp.com/wp-content/uploads/CTS_Whitepaper_Next_Generation_Underwater_Sonar.pdf
https://newshub.sustech.edu.cn/html/202102/30120.html
