Views: 3 Author: Site Editor Publish Time: 2018-04-22 Origin: Site
 |  piezo sound sensor |  |
It is the formation of the inherent torque,it is not only the surface of the crystal polarized charge, but also the piezo electric discs transducer is exposed to the air, the oxygen is through the air for a long time erosion, these charges will be landed on the crystal surface, it is the air of the ion so that the electric charge on the surface and the torque will not appear, but when the crystal mechanical deformation occurs, the piezo ceramics crystal will change, so that the change of the pzt material piezoceramic transducer changes, the value of the surface polarization also changes, so the piezo crystal surface is positive or negative.charge of piezo has a measurable increment, which is the piezoelectric effect.
Good mechanical properties and steady is piezoelectric properties of piezo disk pressure transducer.Piezoelectric ceramics refers to the mixing of oxides (zirconia, lead oxide, titanium oxide, etc. ).it is high temperature sintering, solid opposite should be formed after the polycrystalline,through the DC High-voltage polarization treatment,so that it’s piezoelectric effect of the general designation of the Ferroelectric ceramics, which is a mechanical energy and electrical energy conversion of PZT material piezo vibration sensor.Because of its good mechanical properties and stable piezoelectric properties, piezoelectric ceramics has been widely used in sensors, ultrasonic transducers, micro-displacement devices and other electronic components, as an important material of force, heat, electricity and light sensitive function.
With the continuous research and improvement of materials technology, as well as the rapid development of electronic piezo element sensor, it is used for aerospace and other high-tech fields, the production technology and application development of piezoelectric ceramics, as a new material containing high intelligence, is a hot topic of concern.Piezoelectric ceramic is a class of electronic ceramic materials with piezoelectric properties, the main difference from the typical piezoelectric quartz crystals that do not contain ferroelectric components is that the crystalline phase, which constitutes its main constituent, is a grain of ferroelectric nature.
The spontaneous polarization vectors of various ferroelectric grains are also chaotic orientations because piezoelectric ceramic disc is polycrystalline aggregates with random grain orientations. In order to make the ceramic can display the macroscopic piezoelectricity characteristic, after the piezoelectric ceramic is fired and the end face is complex electrode, it is placed under the strong DC electric field for polarization treatment, so that the original chaotic orientation of each spontaneous polarization vector along the direction of the electric field preferred by polarization treatment of 40khz piezo ceramic disc, after the electric field is canceled, Will retain a certain amount of macro-residual polarization strength, so that ceramics have a certain piezoelectric properties.
