Piezoelectricity

About Piezoelectricity:

• The term “piezoelectric” originates from the Greek words “piezein,” meaning ‘to squeeze’, and “elektron”, for amber, a material known for its association with static electricity.
• Piezoelectricity is a remarkable phenomenon whereby some materials, including quartz, ceramics such as lead zirconate titanate (PZT), and even certain biological substances like bone and tendons, can generate an electric charge in response to mechanical stress.
• This property is the result of their unusual crystal structures.
• Usually, the charges on atoms in the molecules that make them up are symmetric on two sides of an axis.
• When some stress is applied, the molecule becomes distorted, and the asymmetry of charges gives rise to a small electric current.
• Some materials also display an inverse piezoelectric effect, where the application of an electric current induces a mechanical deformation.
• Applications
  • Both direct and inverse piezoelectric materials are widely used in pressure sensors, accelerometers, and acoustic devices, where their ability to convert mechanical signals into electrical signals is crucial.
  • It is also used in quartz watches.
  • Piezoelectric transducers are common in ultrasonic applications, such as intrusion detectors and alarms. 
  • Piezoelectric devices are employed at AF (audio frequencies) as pickups, microphones, earphones, beepers, and buzzers. 
  • In wireless applications, piezoelectricity makes it possible to use crystals and ceramics as oscillators that generate predictable and stable signals at RF (radio frequencies).