Piezoelectricity

Piezoelectricity is the ability of certain crystals to generate a voltage in response to applied mechanical stress. The word is derived from the Greek piezein, which means to squeeze or press. The effect is reversible; piezoelectric crystals, subject to an externally applied voltage, can change shape by a small amount. The effect is of the order of nanometres, but nevertheless finds useful applications such as the production and detection of sound, generation of high voltages, electronic frequency generation, and ultrafine focusing of optical assemblies.

Materials

In addition to the materials listed above, many other materials exhibit the effect, including quartz analogue crystals like berlinite (AlPO4) and gallium orthophosphate (GaPO4), ceramics with perovskite or tungsten-bronze structures

Related Topics:
Ceramic - Perovskite - Tungsten - Bronze

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(BaTiO3,

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KNbO3,

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LiNbO3,

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LiTaO3,

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BiFeO3,

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NaxWO3,

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Ba2NaNb5O5,

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Pb2KNb5O15).

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Polymer materials like rubber, wool, hair, wood fiber, and silk exhibit piezoelectricity to some extent. The polymer polyvinylidene fluoride, PVDF, exhibits piezoelectricity several times larger than quartz.

Related Topics:
Polymer - Rubber - Wool - Hair - Wood - Silk - PVDF

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Bone exhibits some piezoelectric properties: it has been hypothesized that this is part of the mechanism of bone remodelling in response to stress.

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