Views: 64 Author: Site Editor Publish Time: 2022-07-01 Origin: Site
Piezoelectric ceramics refer to polycrystals formed by mixing oxides (zirconia, lead oxide, titanium oxide, etc.) at high temperature and sintering them in a solid state, and they have a piezoelectric effect through DC high voltage polarization treatment. The structure of piezoelectric ceramics is a polycrystalline aggregate with randomly oriented grains, each crystal phase is a ferroelectric grain, and the spontaneous polarization vector of each ferroelectric grain is also chaotically oriented.
Piezoelectric ceramics have good mechanical properties and stable piezoelectric properties. As an important force, heat, electricity, and light sensitive functional materials, piezoelectric ceramics have been used in sensors, ultrasonic transducers, microdisplacers and other electronic materials.
Piezoceramics generate a voltage corresponding to the applied mechanical stress. Often used as energy harvesters, gas igniters and sensors to detect pressure, acceleration and angular velocity.
Piezoelectric ceramics generate displacement corresponding to the applied voltage. This is commonly used in linear actuator applications such as piezoelectric injectors, nanopositioning and anti-vibration systems. Compared with electronic and hydraulic actuators, the advantages of piezoelectric ceramics are fast response, high pressure generation and precise operating resonance.
Piezoceramics have inherent vibrations in shape and size. When an electric field with a certain frequency (called the resonant frequency) is applied, the piezoelectric ceramic vibrates with a large amplitude, thus showing the maximum current flow. This characteristic is used in ultrasonic vibrators such as washing machines, humidifiers, sonars, electrical signal filters and ultrasonic motors.
Irregular crystals clump together to act as piezoelectric materials. The structures of these crystals are not symmetrical, but they still exist in electrical neutral equilibrium. But once mechanical pressure is applied to these piezoelectric crystals, their structure deforms and atoms are pushed, creating crystals that can conduct electrical current. If the same piezoelectric crystal is used and an electric current is applied to it, the crystal will expand and contract, converting electrical energy into mechanical energy.
Disc shape piezoelectric ceramics
Piezoelectric ceramics are piezoelectric materials and have the "piezoelectric effect" that piezoelectric materials usually have. The piezoelectric effect is caused by linear electromechanical interactions between mechanical and electrical states in crystalline materials.
The piezoelectric effect is divided into direct piezoelectric effect and reverse piezoelectric effect. The piezoelectric effect is reversible. When a very small external force acts on it, it can convert mechanical energy into electrical energy. Once the AC voltage is applied between the piezoelectric ceramic sheets, the electrical energy is converted into mechanical energy.
The direct piezoelectric effect results from direct stress on the material. This happens when pressure is applied to a piece of piezoelectric material, such as a crystal or ceramic, typically using two metal plates.
By simply placing a piezoelectric crystal between two metal plates, the material is in perfect balance and does not conduct current. Once the metal plate applies mechanical pressure to the material, the charge imbalance can cause differences when the crystal is disturbed by pressure or other stress.
Piezoelectric Rectangle Element
Excessive negative and positive charges appear on opposite sides of the crystal surface. The metal plate collects these charges, which can be used to generate voltage and send current through the circuit. This process is a direct piezoelectric effect.
A piezoelectric crystal is placed between two metal plates, and the structure of the crystal is in perfect balance without any change. Once electrical energy is applied to the crystal, the structure of the crystal is contracted and expanded.
As the crystal structure expands and contracts, it converts the electrical energy it receives and releases mechanical energy in the form of sound waves.
The current forces the atoms in the material to vibrate back and forth, a process called the inverse piezoelectric effect. The reverse piezoelectric effect has helped develop devices that generate sound waves, such as speakers and buzzers.
A single-layer piezoelectric ceramic element is a product consisting of only one layer of piezoelectric ceramic in which conductive metal electrodes are applied to two opposite sides. Single-layer piezoelectric ceramic components are formed by pressing piezoelectric ceramic powders through conventional processes, such as uniaxial pressing, isostatic pressing and extrusion. The basic technique for making monolayer piezoelectric elements is to use spray-dried particulate material to compress shaped bodies.
Multilayer piezoelectric ceramics consist of several layers of piezoelectric material, alternating with layers of internal electrodes. The inner electrodes are positioned as positive and negative in sequence. All positive electrodes were connected to one external electrode on one side of the piezoelectric ceramic element, and all negative electrodes were connected to the external electrode on the other side of the element. Compared with single-layer piezoelectric ceramic actuators, multilayer piezoelectric ceramic actuators have the advantage of large displacement.
The two most important factors affecting product quality are the purity and grade of raw materials. Product quality is based on raw material grade, raw material ratio, product size and performance to identify, mainly performance. Therefore, when choosing piezoelectric ceramics, the main factors to consider are the raw material of the product, size, dimensional tolerance, shape, performance parameters.
Weifang Jude Electronic Co. Ltd is a manufacturer and supplier of high-quality piezoelectric ceramics for a multitude of electrical functions. As a piezo material supplier, we provide piezoelectric components, piezoelectric ceramic sensors, ultrasonic piezo, and other piezo products.
Its excellent manufacturing facilities and abundant technical strength ensure that products are of high quality. Many kinds of piezoelectric products and power transducers produced by the company have been widely used in high-frequency components, powerful ultrasonic welding, washing, punching, and sensitive ultrasonic fault detection.
Other applications include length measuring, oil well measuring, flow meters and underwater sound, sonar, etc. A good reputation has been built on the quality, reliability and coherence of the products.
If you are looking for a reliable piezo ceramic supplier, we are willing to provide you with high quality products and excellent service, if you need more help please contact us, we will be happy to help you.
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