What is the Piezoelectric Effect – Working and its Applications

The first piezoelectric-effect was invented in the year 1880 by two scientist’s brothers namely ‘Pierre Curie’ & ‘Jacques’. This effect was found from the applied pressure to crystal otherwise quartz forms an electric charge in the material. Afterward, they referred to that scientific fact like the piezoelectric-effect. The “Curie brothers” quickly invented the “inverse piezoelectric effect”, and after they confirmed that whenever an electric-field was required onto crystal terminals, it will lead to the distortion. This is known as the inverse piezoelectric-effect. The name piezoelectric is taken from the Greek word. The meaning of the piezo word is pressed otherwise squeeze, whereas electric means amber.


What is the Piezoelectric Effect?

The Piezoelectric Effect can be defined as the ability of particular materials for generating an electric charge in reply toward applied mechanical pressure. One of the exclusive characteristics of this effect is reversible. That means the materials displaying the straight piezoelectric-effect, and also displays the reverse piezoelectric-effect.

Piezoelectric Effect
Piezoelectric Effect

Whenever piezoelectric material is located beneath mechanical stress, a transferring of the +ve as well as –ve charge carriers within the material takes place, that results during an exterior electrical field. When they inverted, an external electrical field also extends the piezoelectric material.

The applications of piezoelectric-effect mainly involve in the fabrication as well as sound detection, microbalances, generation of high voltages as well as electronic frequency, very fine optical assemblies focusing. This is the foundation of a figure of scientific instrumental methods by atomic resolution like STM, AFM (scanning probe microscopes). The common application of the piezoelectric effect is the explosion source of cigarette lighters.

Piezoelectric Effect Example

As we discussed, the electricity can be generated by squeezing a piezoelectric material. The piezoelectric effect in a crystal is discussed below. The piezoelectric effect happens during piezoelectric material compression. Piezoceramic material like the piezoelectric crystal is placed among the two metal plates that are shown in the below example. The piezoelectricity can be generated whenever the material is squeezed by applying mechanical stress.

Piezoelectric Effect Example
Piezoelectric Effect Example

In the above figure, there will be a voltage potential across the material. The metal plates in the above circuit can be sandwiched by the piezoelectric crystal. The two metal plates gather the charges, which generates a voltage which is known as piezoelectricity.

In this method, the piezoelectric-effect functions as a small battery, as it generates electricity. So this is called the direct piezoelectric effect. There are several devices which can use direct piezoelectric-effects such as pressure sensors, microphones, hydrophones, and sensing types of devices.

Inverse Piezoelectric Effect

The inverse or reverse piezoelectric effect can be defined as, whenever the piezoelectric-effect is reversed. This can be formed by applying electrical energy to make a crystal expand. The main function of this effect is to convert electrical energy into mechanical energy.

Inverse Piezoelectric Effect
Inverse Piezoelectric Effect

By employing this effect, we can develop devices to generate audio sound waves. The best examples of these devices are speakers otherwise buzzers.

The main benefit of using these speakers is that they are extremely thin, which creates them functional in a variety of phones. Even sonar transducers, as well as medical ultrasound, utilize the inverse piezoelectric principle. Non-audio reverse piezoelectric devices comprise actuators as well as motors.

How to Use this Effect?

The piezoelectric crystal twisting can be done in different methods by different frequencies. This twisting can be named as vibration mode. The designing of the crystal can be done into a variety of shapes for attaining diverse vibration modes.
There are several modes have been extended for operating numerous frequency ranges to understand little, cost-effective, as well as high-performance devices.

These modes let us create products to work within the range of low kHz-MHz range. The vibration modes are flexture, lengthwise, area, radius, thickness shear, thickness trapped, surface acoustic wave, and BGS wave.

Ceramics are a significant collection of piezoelectric materials. Murata uses these different vibration modes as well as ceramics for making numerous valuable products like ceramic-discriminators, ceramic-traps, ceramic BPFs (bandpass filters), ceramic-resonators, buzzers as well as SAW filters.

Piezoelectric Effect Applications

The applications of piezoelectric-effect include the following.

  • Please refer the link to know about the piezoelectric effect project namely Footstep Power Generation System.
  • Piezoelectric sensors are used in Industrial Applications for a variety of uses like engine knock sensors, pressure sensors, Sonar Equipment, etc.
  • Piezoelectric actuators are used in Industrial Applications for a variety of uses like Diesel Fuel Injectors, Fast Response Solenoids, Optical Adjustment, Ultrasonic Cleaning, Ultrasonic Welding, Piezoelectric Motors, Stack Actuators, Stripe Actuators, Piezoelectric Relays, etc.
  • Piezoelectric transducers are used in medical applications for a variety of uses like Ultrasound Imaging, Ultrasonic Procedures,
  • Piezoelectric Actuators are used in consumer electronics like Piezoelectric Printers (a dot-matrix printer, inkjet printer), Piezoelectric Speakers (cell phones, ear buds, sound producing toys, musical greeting cards, and musical balloons). Piezoelectric Buzzers, Piezoelectric Humidifiers, and Electronic Toothbrushes.
  • Piezoelectric Materials are used in Musical Applications like Instrument Pickups, and Microphones.
  • Piezoelectricity is used in defense applications like Micro Robotics, Course-changing Bullets, etc.
  • Piezoelectricity is used in some other applications like Piezoelectric Ignitors, Electricity Generation, MEMS (Microelectronic Mechanical Systems), Tennis Racquets, etc.

Thus, this is all about an overview of the piezoelectric effect. From the above information, finally, we can conclude that Piezoelectric-Effect is the capability of particular materials to produce electrical energy when mechanical stress is applied. The main characteristics of this effect are reversible which means that the materials which generate the direct piezoelectric also generates the converse piezoelectric effect. Here is a question for you, what is the piezoelectric effect in ultrasound?