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The direct piezoelectric effect is that piezo ceramic generates an electrical
charge during mechanical distortion or load. During an inverse
piezoelectric effect the piezoceramic body changes under the
influence of an electrical field.
Piezoelectric effect under the influence of external
forces. Depending on the force direction electrical
charges with corresponding polarity are generated.
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| Inverse piezoelectric effect under the influence
of electrical fields. The body changed its dimension
along with the change voltage. |
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| Electric dipoles of domains in piezoelectric ceramic
before and after poling. |
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Material characteristics
| Most
important piezoelectric parameter |
High-performance
application
(transducers with low loss)
|
Low-performance
application
(transducers with low
mechanical grade) |
|
Permittivity factor |
e33T/e0 |
1000 ... 1300 |
1500 ... 4000 |
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Curie-temperature |
[°C] |
300 ... 320 |
200 ... 350 |
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Radial
coupling factor |
|
0,5 ... 0,6 |
0,55 ... 0,65 |
Piezoelectric
charge constant |
d33[10-12CN-1] |
200 ... 325 |
400 ... 650 |
|
Piezoelectric
loss factor |
g33[10-3VmN-1] |
25 ... 29 |
18 ... 29 |
Dielectric
loss factor |
tand[10-3] |
1 ... 5 |
15 ... 20 |
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Mechanical
vibration grade |
|
400 ... 1600 |
50 ... 100 |
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10. Mai 2005
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Piezo properties