The document discusses piezoelectric materials and their applications. It describes how piezoelectric materials generate electric potential when subjected to mechanical stress (direct piezo effect) and how they change dimensions with applied electric fields (inverse piezo effect). Common piezoelectric materials include quartz, ceramics like barium titanate, and polymers. Applications include sensors, actuators, generators, motors, ultrasound, and more. The history of piezoelectric discovery and uses in devices like phones and sonar is also outlined.

1. A presentation by
ABU DARDA
13pstm 19
gd4688
Presentation
on
Submitted to
Department of applied chemistry
Aligarh muslim university

3. Direct Piezoelectric Effect
Piezoelectric Material will generate electric
potential when subjected to some kind of
mechanical stress.

4. The direct Effect :
Generator
 Compression
Effect: Decrease in volume
and it has a voltage with the
same polarity as the
material
 Tension
Effect: Increase in volume
and it has a voltage with
opposite polarity as the
material
F
F

5. Inverse Piezoelectric
Effect
If the piezoelectric material is exposed to an
electric field (voltage) it consequently
lengthens or shortens proportional to the
voltage.

6. The Inverse Piezoelectric
Effect
 If the applied voltage has
the same polarity then the
material expands.
 If the applied voltage has
the opposite polarity then
the material contracts.

7. The History of Piezo
 The name Piezo
originates from the
Greek word piezein,
which means to
squeeze or press.
 The piezoelectric effect
was first proven in 1880
by the brothers Pierre
and Jacques Curie.

8. Developing theories…
 Pierre and Jacques Curie predicted and
demonstrated the piezoelectric effect using tinfoil,
glue, wire, magnets, and a jeweler’s saw.
 They showed that crystals of tourmaline, quartz,
topaz, cane sugar, and Rochelle salt generate
electrical polarization from mechanical stress.
 The converse effect was mathematically derived by
Gabriel Lippman in 1881 using fundamental
thermodynamic principles and was later
experimentally confirmed by the Curies.

9. How are Piezoelectric
ceramics made?
 Fine powders of the component metal oxides are mixed
in specific proportions, then heated to form a uniform
powder.
 The powder is mixed with an organic binder and is
formed into structural elements.
 The elements are fired according to a specific time and
temperature program, during which the powder particles
sinter and the material attains a dense crystalline
structure.
 The elements are cooled, then shaped or trimmed to
specifications. Electrodes are applied to a conducting
material, which is connected to the elements.

10. Crystal Structure and
Dipole Moments
 A traditional piezoelectric ceramic is a mass
of perovskite crystals. Each crystal consists
of a small tetravalent metal ion, usually
titanium or zirconium, in a lattice of larger
divalent metal ions, usually lead or barium,
and O2- ions
 At temperatures below the Curie point,
however, each crystal has tetragonal or
rhombohedral symmetry and a dipole
moment. Above the Curie point each
perovskite crystal in the fired ceramic
element exhibits a cubic symmetry with no
dipole moment.

12. Polarizing Piezoelectric
Material
 Adjoining dipoles form regions of local alignment called domains. The
alignment gives a net dipole moment to the domain, and thus a net
polarization. The direction of polarization among neighboring domains is
random, however, so the ceramic element has no overall polarization.
 The domains in a ceramic element are aligned by exposing the element
to a strong, direct current electric field, usually at a temperature slightly
below the Curie point
 When the electric field is removed most of the dipoles are locked into a
configuration of near alignment

13. Types of Piezoelectric
Materials Naturally occurring crystals:
Berlinite (AlPO4), cane sugar, Quartz, Rochelle salt, Topaz, Tourmaline
Group Minerals, and dry bone (apatite crystals)
 Man-made crystals:
Gallium orthophosphate (GaPO4), Langasite (La3Ga5SiO14)
 Man-made ceramics:
Barium titanate (BaTiO3), Lead titanate (PbTiO3), Lead zirconate
titanate (Pb[ZrxTi1-x]O3 0<x<1) - More commonly known as PZT,
Potassium niobate (KNbO3), Lithium niobate (LiNbO3), Lithium
tantalate (LiTaO3), Sodium tungstate (NaxWO3), Ba2NaNb5O5,
Pb2KNb5O15
 Polymers:
Polyvinylidene fluoride (PVDF)

14. Sonic and Ultrasonic
Applications
 Sonar with Ultrasonic time-
domain reflectometers
 Materials testing to detect
flaws inside cast metals
and stone objects as well
as measure elasticity or
viscosity in gases and
liquids
 Compact sensitive
microphones and guitar
pickups.
 Loudspeakers

15. Pressure Applications
 Transient pressure measurement to
study explosives, internal combustion
engines (knock sensors), and any other
vibrations, accelerations, or impacts.
 Piezoelectric microbalances are used as
very sensitive chemical and biological
sensors.
 Transducers are used in electronic drum
pads to detect the impact of the
drummer's sticks.
 Energy Harvesting from impact on the
ground
 Atomic force and scanning tunneling
microscopes.
 Electric igniters and cigarette lighters

16. Consumer Electronics
Applications
 Quartz crystals resonators as
frequency stabilizers for
oscillators in all computers.
 Phonograph pick-ups
 Accelerometers: In a
piezoelectric accelerometer a
mass is attached to a spring that
is attached to a piezoelectric
crystal. When subjected to
vibration the mass compresses
and stretches the piezo electric
crystal. (iPhone)

17. Motor Applications
 Piezoelectric elements can be used
in laser mirror alignment, where
their ability to move a large mass
(the mirror mount) over microscopic
distances is exploited. By
electronically vibrating the mirror it
gives the light reflected off it a
Doppler shift to fine tune the laser's
frequency.
 The piezo motor is viewed as a high-
precision replacement for the
stepper motor.
 Traveling-wave motors used for
auto-focus in cameras.

18. Procedure
1) Attach a mirror to the piezoelectric buzzer. Position that laser so that
the beam can reflect off of the mirror and hit the wall across the room.
2) Connect the function generator to the Piezoelectric device. Find the
resonant frequency of the device by slowly increasing the frequency at
10Vp-p.The laser will vibrate the most at the resonant frequency.
3) Measure the diameter of the laser without any signal. Then measure
the diameter of the laser with the AC signal applied.
4) Calculate the displacement of the laser and divide it by two to get the
amplitude of the magnified change in volume for the piezoelectric
material.
5) Measure the distance from the piezo to the wall and to the laser. Also
measure the height of the laser and reflected beam in relation to the
piezo.
6) Calculate the change in volume for the piezoelectric material.

20. Error Analysis
The laser’s diameter expands over a distance.
The quality of the mirror scatters the laser.
The sinusoidal vibration of the material amplifies the laser’s displacement.

21. Works Cited
 Images:
1. http://en.wikipedia.org/wiki/Image:SchemaPiezo.gif
2.
http://images.google.com/imgres?imgurl=http://www.hvwtech.com/products/266/35170_PV.jpg&imgrefurl=http://www.hvwtech.com/products
=
3.
http://images.google.com/imgres?imgurl=http://surveying.wb.psu.edu/psu-surv/SURIs/Images/NOAA_sonar.gif&imgrefurl=http://surveying.wb.
=
4.
http://images.google.com/imgres?imgurl=http://www.pc-control.co.uk/images/curie1.jpg&imgrefurl=http://www.pc-control.co.uk/piezoelectric_
=
5.http://www1.eere.energy.gov/vehiclesandfuels/pdfs/deer_2005/session1/2005_deer_troy.pdf
6. http://ch.mt.com/mt_ext_files/FilterHierarchy/ProductFamily/1/MX-UMX_FilterHierarchy-ProductFamily_1101466637484_files/micro_big.jpg
7.
http://images.google.com/imgres?imgurl=http://euroross.blogspot.com/Moscow%2520Traffic%25202.jpg&imgrefurl=http://euroross.blogspot.c
=
8.
http://images.google.com/imgres?imgurl=http://farm1.static.flickr.com/116/252342964_2fffa201a8.jpg&imgrefurl=http://www.flickr.com/photo
=
 Information:
1. http://www.piezo.com/tech1terms.html
2. http://www.piezo.com/tech4history.html
3. http://www.piezoelectrics.net/piezoelectrichistory.htm
4. http://www.americanpiezo.com/piezo_theory/index.html
5. http://www.cedrat-groupe.com/
6. http://www.sensotec.com/accelerometer_faq.asp?category=All
7. http://www.apple.com/iphone/features/index.html#accelerometer
8. http://www.patent-invent.com/electricity/inventions/piezoelectricity.html
9. http://en.wikipedia.org/wiki/Piezoelectricity