The Principle and Product Application of Piezoelectric Ceramics
Piezoelectric ceramics are an information functional ceramic material that can convert mechanical energy and electrical energy into each other - piezoelectric effect. In addition to piezoelectricity, piezoelectric ceramics also have dielectric properties, elasticity, etc. They have been widely used in medical imaging, ultrasonic amplitude rods, ultrasonic transducers, ultrasonic motors, etc. Piezoelectric ceramics are made by using their materials to cause relative displacement of positive and negative charge centers under mechanical stress, resulting in polarization and the appearance of opposite sign bound charges on the surfaces of both ends of the material, known as piezoelectric effect. They have sensitive characteristics and are mainly used in the manufacture of ultrasonic transducers, underwater acoustic transducers, electroacoustic transducers, ceramic filters, ceramic transformers, ceramic frequency detectors, high-voltage generators, infrared detectors, surface acoustic wave devices, electro-optical devices, ignition devices, and piezoelectric gyroscopes
Piezoelectric ceramics are a type of electronic ceramic material with piezoelectric properties. The main component of piezoelectric ceramic materials is ferroelectric grains, which are polarized by a strong DC electric field to optimize the polarization vectors of the originally disordered ferroelectric grains along the direction of the electric field. After polarization treatment, piezoelectric ceramics retain a certain macroscopic residual polarization strength after the electric field is cancelled, thus possessing certain piezoelectric properties.
Simply put, piezoelectric properties refer to the ability to convert mechanical energy and electrical energy into each other. The deformation of a medium caused by the action of force, resulting in surface electrification of the medium, belongs to the positive piezoelectric effect. Conversely, if a certain excitation electric field is applied to the medium, it will undergo mechanical deformation, known as the inverse piezoelectric effect. The piezoelectric effect of piezoelectric ceramics has been applied by scientists in various fields closely related to human life, to achieve functions such as energy conversion, sensing, driving, frequency control, etc. By utilizing the positive piezoelectric effect of piezoelectric ceramics, piezoelectric igniters, bomb detonators, and other devices can be made. For example, common electronic lighters in daily life utilize the property of piezoelectric ceramics to convert mechanical energy into electrical energy. Moreover, due to the sensitive nature of piezoelectric ceramics, they can convert extremely weak mechanical vibrations into electrical signals, which can be used in fields such as sonar, meteorological detection, remote sensing, and environmental protection. When piezoelectric ceramics are used to make piezoelectric seismometers, they can accurately measure the intensity of earthquakes and indicate the direction and distance of earthquakes. Piezoelectric ceramics not only possess unique piezoelectric properties, but also demonstrate advantages such as good frequency stability, high precision, high anti-interference ability, and wide frequency range when applied in frequency control devices such as resonators and filters.
Piezoelectric ceramics have a wide range of applications, including ultrasonic transducers. Ultrasonic transducer is a device that utilizes the inverse piezoelectric effect of piezoelectric ceramics to convert input high-frequency electrical power into mechanical power (ultrasonic waves) and transmit the mechanical power. Its core component is piezoelectric ceramics, which can be changed in shape and specifications to adapt to different working forms and frequency requirements of different ultrasonic transducers.
