Views:0 Author:Site Editor Publish Time: 2019-12-30 Origin:Site
The performance indicators of piezo ceramic crystals are as follows:
(1) free dielectric constant / E0: 1000-6000;
(2) dielectric loss and (2-12) '10-3;
(3) Piezoelectric strain coefficient d33: 300 ~ 600 PC / n;
(4) Plane electromechanical coupling coefficient KP: 0.56 to 0.70;
(5) Mechanical quality factor QM: 100 ~ 2000;
(6) Curie temperature Tc: 280 ~ 400 ℃.
The conductivity of the coating of the piezo ceramic disc transducer is mainly related to the conductivity, content, particle size and compatibility of the polymer and filler particles. The finer the carbon black particles, the closer the network chains are packed, and the larger the specific surface area. The more mass particles there are, the more advantageous it is to form a chain-like conductive structure in the matrix. Under the certain other conditions, the dispersion of carbon black particles in the polymer will determine the conductivity of the conductive coating. When the carbon black particles reach the nanometer level, the specific surface area is very large, and flocculation easily occurs during the preparation of the coating. The coupling agent will significantly affect the dispersibility and wettability of the filler in the matrix. Therefore, it is necessary to study different coupling agents Effect on the conductive properties of the coating. In addition, carbon-based composite conductive coatings are prone to cracking during film formation, which leads to poor conductive stability and affects the application of the coating. One of the effective treatment methods is to add a coupling agent. Therefore, the application of the coupling agent will directly determine the conductivity of the carbon-based composite conductive coating.