Piezoelectric Materials Report:-

By: Abdelrahman Hesham Abdalla
ID: 1105014

"Piezoelectricity, electricity generated by certain crystals and ceramics when they are deformed by mechanical pressure."
Simply, the piezolectricity is an accumulation of charges resulted from applying Mechanical pressure inside of a material, like crystals or ceramics. These charges are then released in a form of a potential difference or an electric charge.
Piezoelectricity is a reversible effect, meaning it can be used to get a Mechanical stress or work from an introduced electric charge.













History

The piezoelectric effect occurs only in non conductive materials. The effect was discovered in 1880 by the Jacques and Pierre Curie brothers. They found out that when a mechanical stress was applied on crystals such as tourmaline, tourmaline, topaz, quartz, Rochelle salt and cane sugar, electrical charges appeared, and this voltage was proportional to the stress. Piezoelectric materials can be divided in 2 main groups: crystals and cermaics. The most well-known piezoelectric material is quartz (SiO2).

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Mechanism

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Applications


The piezoelectric effect is particularly useful in converting mechanical strain into electrical impulses and converting electrical impulses into mechanical strain. Piezoelectric crystals and ceramics are used in phonograph cartridges, microphones, and other many applications like:


Piezoelectric Sensors
They are used for quality assurance,process control and for research and development in many different industries.
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Ultrasonic transducers

  • The transducer can act as a sensor and an actuator in imaging applciations



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Piezoelectric motors
A piezo motor is based on the change in mechanical shape of a piezoelectric material when an tension is applied.




References