10-08-2013, 02:47 PM
PIEZOELECTRICITY
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What is piezoelectricity ?
The word piezoelectricity is derived from Greek word
“piezenin” meaning “to press”.
The original meaning of the word “piezoelectricity” implies “pressure electricity” -the generation of electric field from applied pressure.
It is a reversible process
DISCOVERY AND INSIGHTS
In 1880, Pierre Curie & Jacques Curie predicted & demonstrated piezoelectricity using tinfoil,glue,wire ,magnets & a jeweler’s saw.
Hankel was the scientist who coined the term “piezoelectricity”.
The first serious application work took place in the year 1917
during World war II .
Mechanism of piezoelectricity
The application of a mechanical stress produces in certain dielectric (electrically non conducting) crystal an electric polarization (electric dipole per cubic meter),which is proportional to stress.
A voltage develops across the crystal & if the crystal is short circuited
a flow of charge can be observed.
This phenomenon is known as piezoelectric effect.
ADVANTAGES OF PIEZOELECTRICITY
Supply of electrical power to remote installations like lighthouse,
defence observation post, astronomical observatory etc.
There is no need of installation of power transmission line & its
maintenance, so reduction in cost .
Use of DG set produces sound which can be easily picked up by the enemy in case of defence installation, so it can be used in defence.
There is no problem of pollution in this process.
CONCLUSION
Commercial success of Japanese efforts.
Even in India the need of piezoelectric products is in a all time high.
Besides in the fields of robots they are used in micro robots that walk by using piezoceramic legs. This can further enhance the future probability in areas of piezoelectricity.