Basic interpretation of piezoelectric ceramics
Piezoelectric ceramics is a kind of electronic ceramic material with piezoelectric properties. The main difference from the typical piezoelectric quartz crystals that do not contain ferroelectric components is that the crystalline phase comprising the main components is a grain of ferroelectric nature. Ceramics are polycrystalline aggregates with random grain orientations.
Therefore, the spontaneous polarization vectors of the ferroelectric grains are also chaotic. In order to make the ceramic can display the macroscopic piezoelectric characteristic, it must be in the piezoelectric ceramic and after the end face is complex electrode, it is placed under the strong DC electric field to carry on the polarization processing, so that the original chaotic orientation of each spontaneous polarization vector along the electric field direction preferred orientation. After the polarization treatment of piezoelectric ceramics, after the electric field cancellation, will retain a certain macro-residual polarization strength, so that ceramics have a certain piezoelectric properties.