American International University-Bangladesh(AIUB)

Piezoelectric MaterialsPresented To: RETHWAN FAIZGroup Members:

FARHIN, REHNUMA 14-25520-1MIRAZ, MAGFURUL AWWAL 14-25537-1

AHMED, MD. FOYSAL 14-25539-1CHOWDHURY, TULSI 14-25727-1

MUIN, MUHTASIM 14-25600-1RAHMAN, MD. RABBI 14-26318-1

Content What is PiezoelectricityWhat is Piezoelectric materialsMechanism of PiezoelectricMotion of Piezoelectric ActuatorsCommon Piezoelectric materialsConfigurationsHardware FeaturesApplications of PiezoelectricAdvantages and DisadvantagesArtificial materialsSignal ConditioningConclusion

What is Piezoelectricity ?

Piezoelectricity is the electric charge that accumulates in certain solid materials in response to applied mechanical stress. The word Piezoelectricity means electricity resulting from pressure.

The larger circles represent silicon atoms, while the smaller ones represent oxygen.

What is Piezoelectric?

Piezoelectric:Piezoelectrics are materials that can create

electricity when subjected to a mechanical stress. They will also work in reverse, generating a

strain by the application of an electric field.The word originates from the greek word

“piezein”, which means “to press”. Discovered in 1880 by Pierre Curie in quartz crystals

Mechanism of Piezoelectric

The nature of the piezoelectric effect is closely related to the occurrence of electric dipole moments in solids. The latter may either be induced for ions on crystal lattice sites with asymmetric charge surroundings or may directly be carried by molecular groups. The dipole density or polarization (dimensionality [Cm/m3] ) may easily be calculated for crystals by summing up the dipole moments per volume of the crystallographic unit cell. As every dipole is a vector, the dipole density P is a vector field. Dipoles near each other tend to be aligned in regions called Weiss domains. The domains are usually randomly oriented, but can be aligned using the process of poling, a process by which a strong electric field is applied across the material, usually at elevated temperatures. Not all piezoelectric materials can be poled.

A piezoelectric disk generates a voltage when deformed (change in

shape is greatly exaggerated)

Motion of Piezoelectric Actuators

• Shear actuators• Disk bimorph• Bimorph blenders

Common Piezoelectric Materials

Configurations

• Red indicates the crystal• Arrows indicate the direction of applied force• The compression design features high rigidity, making it

useful for implementation in high frequency pressure and force sensors

Configurations

Hardware Features• Infineon C164CI 16 bit Processor• 20 MHz clock rate• 256kB SRAM• 256kB Flash ROM• CAN 2.0B controller• 250 kbps raw data rate• RS-232 Interface• 115.2 kbps UART• DB-9 serial interface• 3 channel LISA interface• Left, Right, and microphone channels• Optional pre-amp for microphone

Applications of Piezoelectric

Power generating sidewalkGyms and workplacesMobile keypads and keyboards

Applications of Piezoelectric

Applications of Piezoelectric

Applications of Piezoelectric

Artificial materials Polycrystalline, piezoceramics are man

made materials which are forced to become piezoelectric by applying large electric field.

High charge sensitivity Materials available which operate at 1000

F (540 C) Characteristics vary with temperature

Signal Conditioning

Advantages and Disadvantages

Conclusion• Piezoelectricity is a revolutionary source for

“GREEN ENERGY”• Flexible piezoelectric materials are attractive for

power harvesting applications because of their ability to withstand large amounts of strain.

• Convert the ambient vibration energy surrounding them into electrical energy.

•  Electrical energy can then be used to power other devices or stored for later use.

Thank You