pi2009
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Physik
Instrumente
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C
at120E
Inspirations2009
08/10.18
Piezo Nano Positioning
the maximum voltage range
(>105 V) with an operating fre-
quency up to 1000 Hz. After one
month of continuous operation
there were no degradations in
piezo performance to be meas-
ured, neither mechanic con-
cerning the displacement, nor
electrical concerning electrical
capacitance or resonant fre-
quency. (Dr. Bosotti et al.,
University of Milano, Italy,
2005)
Large Operating Temperature
Range , Optimum UHV
Compatibility - Minimum
Outgassing
Another advantage of fully
ceramic-encapsulation PICMA
®
AC tests were performed for 4.0 x 10
9
cycles at 8 samples PICMA
®
5x5x18 using a
116 Hz-sine wave excitation (1.0 x 10
7
cycles per day) at a unipolar operating voltage of
100 V, 15 MPa preload. Control measurements were taken every 10
9
cycles. There was
no significant decrease in displacement.
Continuous Dynamic
Operation
Here, the well-known lifetime-
limiting factors of conventional
designs are humidity, crack for-
mation inside the ceramic lead-
ing to rising leakage currents
and delamination of electrodes
under extreme dynamic condi-
tions.
PI reduces the cracking proba-
bility by a special patented
design where segmented slots
take care of excessive tensional
stresses. Furthermore, the spe-
cial electrode design ensures
excellent, stable, electric con-
tact even after billions of
cycles.
PICMA
®
multilayer piezo actua-
tors show no significant de-
crease in displacement even
after many billions of cycles.
Long-Term Test under
Cryogenic Conditions
To suit an application requiring
10 years minimum lifetime
under cryogenic conditions,
accelerated lifetime tests with
PICMA
®
piezo actuators have
been successfully performed.
Inserted in a cryogenic bath of
liquid nitrogen (75 K), the piezo
is placed in a vacuum chamber
(2 10
-3
mbar) and subjected to
dynamic operation at 90 % of
PICMA
®
Piezo Actuators
actuators is the extended oper-
ating temperature range, up to
150 °C, a huge improvement
over the 80 °C limit common
for other, polymer-insulated,
monolithic actuators. The heat
generation in dynamic opera-
tion is proportional to the oper-
ating frequency. Thus, a higher
operating temperature allows
for higher operating frequen-
cies and duty cycles. Addi-
tionally, the lack of polymer
insulation and the high Curie
temperature make for optimal
ultra-high-vacuum compatibili-
ty (no outgassing / high bake-
out temperatures, up to 150 °C).
1-67
Piezo Nano Positioning
DC-Servo & Stepper Actuators
Piezo Actuators & Components
PiezoWalk
®
Motors / Actuators
PILine
®
Ultrasonic Motors
Nanopositioning / Piezoelectrics
Linear Actuators & Motors
Unpackaged Stack Actuators
Guided / Preloaded Actuators
Nanometrology
Micropositioning
Patches /Benders/Tubes /Shear..
Index
Mounting and Handling Guidelines
Adherence to the following
guidelines will help you obtain
maximum performance and
lifetime from your piezo actu-
ators: Do not use metal tools
for actuator handling. Do not
scratch the coating on the side
surfaces. The following precau-
tions are recommended during
handling of piezoelectric actua-
tors:
I. Piezoelectric stack actuators
without axial preload are
sensitive to pulling forces. A
preload of up to 50% of the
blocking force is generally
recommended.
II. Piezoelectric stack actuators
may be stressed in the axial
direction only. The applied
force must be centered very
well. Tilting and shearing
forces, which can also be in-
duced by parallelism errors
of the endplates, have to be
avoided because they will
damage the actuator. This
can be ensured by the use
of ball tips, flexible tips, ade-
quate guiding mechanisms
etc. An exception to this
requirement is made for the
PICAShear actuators, be-
cause they operate in the
shear direction.
III. Piezoelectric stack actuators
can be mounted by gluing
them between even metal
or ceramic surfaces by a
cold or hot curing epoxy,
respectively. Ground sur-
faces are preferred. Please,
do not exceed the specified
working temperature range
of the actuator during curing.
IV. The environment of all actu-
ators should be as dry as
possible. PICMA
®
actuators
are guarded against humidi-
ty by their ceramic coating.
Other actuators must be pro-
tected by other measures
(hermetic sealing, dry air
flow, etc).
The combination of long-
term high electric DC fields
and high relative humidity
values should be avoided
with all piezoelectric actua-
tors.
V. It is important to shortcir-
cuit the piezoelectric stack
actuators during any hand-
ling operation. Temperature
changes and load changes
will induce charges on the
stack electrodes which
might result in high electric
fields if the leads are not
shorted: Should the stack
become charged, rapid dis-
chargingespecially with-
out a preloadmight dam-
age the stack. Use a resistor
for discharging.
VI. Prevent any contamination
of the piezo ceramic sur-
faces with conductive or
corrosive substances. Iso-
propanol is recommended
for cleaning. Avoid acetone
and excessive ultrasonic
cleaning at higher tempera-
tures.
No pulling force without preload
No lateral force or torque
Ball tips or flexures to decouple lateral forces or
bending forces
Ball tips or flexures to decouple bending forces
Bolting between plates is not recommended
www.pionline.it, www.pifrance.fr, www.pi-china.cn, www.goa-tech.co.il, www.alt.nl, www.bfioptilas.es, www.pi.ws, www.piceramic.de, www.pi-usa.us, www.pi-usa.us, www.pi-japan.jp, www.pi-japan.jp, www.physikinstrumente.co.uk, www.dyneos.ch, www.parameter.se, dms@deepms.com, www.deepms.com, www.warsash.com.au, www.parameter.se, www.eliovac.com.ar, www.rsdobrasil.com.br, www.woojoohitech.com, www.cairnhill.com, www.tetmakina.com, Seewww.piceramic.com, Seep.1-94ff.andwww.piceramic.com, Seewww.piceramic.com, Seealsowww.piceramic.com, andoscillatingmotione.g.in, info@pi-usa.us, www.pi-usa.us, info@pi-usa.us, www.pi-usa.us, info@pi-japan.jp, www.pi-japan.jp, info@pi-japan.jp, www.pi-japan.jp, info@pi-china.cn, www.pi-china.cn, info@pifrance.fr, www.pifrance.fr, uk@pi.ws, www.physikinstrumente.co.uk, info@pionline.it, www.pionline.it, info@piceramic.de, www.piceramic.de,
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