Avoiding dynamic forces may bring the risk of damage to the piezoelectric ceramic sheet

Publish Time: 2020-01-08 Origin: Site

As we all know, after applying a voltage to a piezoelectric ceramic sheet, it will expand with the increase of the driving voltage. When the voltage of piezo ceramics drops, the piezoelectric ceramic sheet will shrink. Because the piezoelectric ceramic sheet has an extremely fast response speed, when the current is large enough .At this time, the piezo ceramic transducers will rapidly expand and contract with the increase or decrease of the driving voltage. At this time, the piezoelectric ceramic sheet itself will generate tensile and compressive forces. These two forces appear alternately, which we call dynamic forces. How to avoid the risk of damage to the piezoelectric ceramics by dynamic forces?We need to understand the dynamic force during use, determine the size of the dynamic force by calculation, and then reduce the possibility of damage to the piezoelectric ceramics by the dynamic force by reducing the frequency or load.

After the piezo ceramics poling sheet is loaded, the power generated will be greater. Therefore, we usually choose encapsulated piezoelectric ceramics with a certain pretension for dynamic applications, such as PST 150 series and PST 1000 series, PST 1000/35 / xx VS45 series piezoelectric ceramics, with a pretension force of 6000 N, This means that this series of piezoelectric ceramics can withstand a maximum dynamic force of 6000 N. Piezoceramic sheets without pre-stretching can only be used at very low frequencies. For example, we have selected a packaged piezoelectric ceramic sheet PST 1000/16/200 vs22 5 and it can use it at a maximum frequency of 300 Hz under a load of 10Kg. According to the dynamic force formula, the frequency is 300 Hz, the dynamic force is 3655 N, and the pretension force of the piezoelectric ceramic plate is 1500 N, which is much larger than the pretension force. When used at this frequency, it will definitely cause damage to the piezoelectric ceramic sheet. The dynamic force formula is also used for calculations, assuming a dynamic force of 1500 n and a maximum use frequency of 192 Hz.

Note: 1. The dynamic operation of the Pzt powder ceramic piezoelectric ceramic sheet requires the addition of a heat sink to quickly conduct the heat generated by the piezoelectric ceramic sheet.
2.Dynamic operation needs to ensure that the piezoelectric ceramic sheet is not affected by lateral and shear forces.

Avoiding dynamic forces may bring the risk of damage to the piezoelectric ceramic sheet

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