Basic Characteristics of Piezoelectric Ceramics

With the enlargement o f the application of piezo disc element,piezoelectric ceramics is a new type of electronic components. Its advantages own light weight, high resolution, small volume, high frequency, high intensity piezo ring and large output. It have been widely used In the fields of aerospace, optics, machinery manufacturing, medical imaging, acoustic sensors, acoustic transducers, ultrasonic motors, bio engineering, electronics, robots and other technical fields .

 Piezoelectric ceramic is a dielectric, dielectric has two effects under the action of the electric field , it is electrostrictive effect and reverse piezoelectric effect. The effect of  electrostrictive is that the strain is caused by the induced polarization under the action of the electric field, and the strain is independent of the direction of the electric field. The magnitude of the strain is proportional to the square of the electric field, while the inverse piezoelectric effect refers to the effect of the dielectric in the external electric field .The strain is proportional to the size of the electric field, and the direction of the strain is related to the direction of the electric field. Piezoelectric ceramics is using its material under the action of mechanical stress, caused by the relative displacement of the positive and negative charge center polarization occurs, resulting in the opposite ends of the material .it appears on the opposite side of the bond charge that is produced by the piezoelectric effect.

 

Piezoelectric materials have been widely used in the fields of sensors, transducers, nondestructive testing and communication technology as machine, electricity, sound, light and heat sensitive materials. Piezoelectric ceramics are mainly used in the manufacture of ultrasonic transducers, underwater acoustic transducers, electroacoustic transducers, ceramic filters, ceramic transformers, ceramic discriminators, high voltage generators, infrared detectors, surface acoustic wave devices, electric light.