Basic Knowledge

What is piezoelectric ceramic?

Piezoelectric ceramics are fine ceramics with piezoelectricity. They are used in various fields in our daily lives, as they can convert electric energy into kinetic energy (such as ultrasound and driving force) or kinetic energy into electric energy. Lead zirconate titanate (PZT), which we also provide, shows high piezoelectric performance.

Search for PZT-based piezoelectric
ceramic product

Direct piezoelectric effect

Pressure is applied to the piezoelectric element to generate strain

Voltage (corresponding to strain) is generated

Reverse piezoelectric effect

Voltage is applied to the piezoelectric element

The element generates strain corresponding to the voltage

Mechanism of ultrasound generation

By utilizing reverse piezoelectric effect, piezoelectric ceramics extend and shrink (vibrates) depending on the frequency of the voltage that is applied. This vibration generates ultrasound.

What is piezoelectric single crystal?

Compared to ceramic, which is a polycrystalline material with random crystal orientations, a single crystal is a substance in which the crystal orientation only has one direction regardless of its position. Single crystal has superior piezoelectricity compared to conventional piezoelectric ceramics as the crystal orientation is completely aligned and no grain boundary exist in it.
TFT Corporation provides single crystal products that is composed of lead magnesium niobate-lead titanate (PMN-PT) as their main component. Single crystals are produced by Tayca Corporation (Japan) and TRS technologies, Inc.(The U.S).

Search for piezoelectric single crystal
PMN-PT/PIN-PMN-PT

Application examples of piezoelectric material

Function	Application
Electricity Ultrasound Ultrasound Electricity	Ultrasonic diagnostic devices, endoscopes
	Intravascular ultrasound (IVUS)
	Sensors: flowrate, acceleration, space, liquid level, sound pressure
	Non-destructive Testing devises
	Filters, oscillators
	Sonar, fish finders
	HAPTICS
Kinetic energy Electricity	Sensors: Flow rate, vibration, pressure, shock detection sensors, gyrosensor electronic instruments
Kinetic energy Electricity	Spark plugs, vibration power generation, electronic lighters
Electricity Ultrasound	Ultrasonic cleaning machines
Electricity Ultrasound	Treatment devices, ultrasonic therapy devices, ultrasonic scalpels, scalers, cutters, atomizers, positioning
Electricity Ultrasound Heat	High-intensity focused ultrasound (HIFU)
Electricity Ultrasound Heat	Wire bonders (bonding devices for electronic parts)
Electricity Kinetic energy	Endoscopes
	Ink jet, fuel injection
	Artificial muscles (robots), ultrasonic motors (cameras, pumps)
	Actuators (buzzers, speakers)

Typical requirements for piezoelectric ceramics and examples of recommended materials

Needs	Characteristics		Recommended material
To increase the vibration To increase the transmission output	Coupling Coefficient	Large	L-145N L-155N
	Relative permittivity	Large
	Piezoelectric charge constant d	Large
To increease the reception sensitivity	Coupling Coefficient	Large	L-1A L-6A L-201F
	Relative permittivity	Small
	Piezoelectric voltage constant g	Large
To use in a high-temperature environment	Curie Temperature	Large	L-1A, H-8
To drive at a high voltage	Mechanical Quality Factor	Large	H-8
To suppress the heat generation during operation	Dielectric Loss Factor	Small	H-8
To suppress the heat generation during operation	Mechanical Quality Factor	Large	H-8

Manufactured by Tayca (in Japan)