Researchers from the Indian Institute of Technology Madras (IIT-M) and the Defence Research and Development Organisation (DRDO) recently developed piezoelectric MEMS (micro electro mechanical system) technology for underwater communication.
- Piezoelectricity (also called the piezoelectric effect) is the appearance of an electrical potential (a voltage, in other words) across the sides of a crystal when you subject it to mechanical stress.
- In the reverse piezoelectric effect, a crystal becomes mechanically stressed (deformed in shape) when a voltage is applied across its opposite faces.
- Thus, Piezoelectric materials allow the conversion of energy from the mechanical domain to the electrical domain and vice versa.
- It is due to the spontaneous separation of charge with certain crystal structures under the right conditions.
- There are a wide variety of materials which exhibit this phenomenon, including natural quartz crystals, semi-crystalline polyvinylidene polymer, polycrystalline piezoceramic, bone and even wood.
- They can be used to create various sensors or actuators.
- 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).
Q1) What are Piezoelectric materials?
Piezoelectric materials are materials that have the ability to generate internal electrical charge from applied mechanical stress. The term piezo is Greek for "push."