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Kistler Singapore
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Piezoelectric Materials
 Quartz
Quartz meets all of these requirements which are mentioned in the introduction and is therefore an ideal piezoelectric material. It can be produced synthetically and exhibits other qualities, which are beneficial for measurement. A synthetic quartz element, for example, can be used in temperatures of up to 400 °C. Quartz can be cut in different angles to exhibit sensitivity to pressure or shear forces, depending on which of the three piezoelectric effects is to be used. The high natural frequency of the quartz element has advantages when measuring high-speed dynamic processes. Due to the minimal deflection, measurement of slow, quasistatic phenomena will only involve extremely small measuring errors.
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 PiezoStar®
PiezoStar crystals belong to the family of calcium gallogermanates quartz isotypes. Due to the same crystallographic class as quartz, it is possible to obtain the same crystal cuts (longitudinal, transversal and shear). However, unlike quartz, PiezoStar crystals do not have a phase transition point below melting point (above 1300 °C) and this explains their excellent stability to extreme temperatures. They are consequently perfect for use in extremely high temperature environments like engines. Although PiezoStar crystals are also highly sensitive and can be synthesized like quartz, their loading capacity is lower and production costs higher.
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 Piezoceramics
In addition to single-crystal piezo-elements such as quartz or PiezoStar®, polycrystalline forms termed piezoceramics can exhibit piezoelectric properties. Lead zirconate titanate (PZT) is the main compound of this type used for sensors. These elements can be synthesized in large quantities at low cost using the sintering process. The advantages of piezoceramics lie mainly in ease of production and high sensitivity. However, relatively poor thermal stability means they can only be used up to 250 °C, and their pyroelectric effect can falsify measurement. The pyroelectric effect is due to deformation of the lattice structure of the piezoelement caused by a change in temperature. This generates an additional charge. The change in temperature can falsify measurement where an externally applied force rather temperature variation is the relevant measurand. Back to Piezoeffect |
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