Rapid adhesive curing using microwaves and induction · Rapid adhesive cuRing using micRowaves and...
Transcript of Rapid adhesive curing using microwaves and induction · Rapid adhesive cuRing using micRowaves and...
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Rapid adhesive cuRing using micRowaves and induction
Status quo
Adhesive bonding processes in virtually
all areas of industrial production require
that the adhesive curing process is rapid,
highly effective, and is adapted to the serial
production.
In addition to rapid curing using UV radi-
ation, which is only possible for substrates
that transmit light, thermally accelerated
adhesive curing is a suitable way for
integrating curing into the process chain.
The traditional supply of heat via ovens
is, however, too slow here and does not
provide location-specific or material-specific
heating.
Range of services offered by
Fraunhofer IFAM
Microwave radiation and inductive
heating offer much promise for the rapid
thermal curing of adhesives. Both methods
are being used and constantly further
developed by the Fraunhofer Institute for
Manufacturing Technology and Advanced
Materials IFAM.
The sections Adhesives and Polymer
Chemistry as well as Adhesive Bonding
Technology at Fraunhofer IFAM have exten-
sive experience in selecting and modifying
adhesives to meet the requirements of
specific processes. These adhesive systems
are used for accelerated adhesive curing,
with the focus being on the plant techno-
logy and process parameters.
In close cooperation with plant manu-
facturers we develop a solution for your
specific requirements and then integrate
the process into your production.
1+3 Microwave oven of the Fraunhofer IFAM
for qualifying curing processes.
2 Use of induction curing for selective
adhesive heating between non-metallic
components (glass/plastic).
Fraunhofer Institute for
Manufacturing Technology
and Advanced Materials IFAM
– Adhesive Bonding Technology
and Surfaces –
Wiener Strasse 12
28359 Bremen | Germany
Institute director
Prof. Dr. Bernd Mayer
Contact
Adhesive Bonding Technology
Dr.-Ing. Michael Adam
Phone +49 421 2246-542
Adhesives and Polymer Chemistry
Dipl.-Ing. (FH) Andreas Lühring
Phone +49 421 2246-494
www.ifam.fraunhofer.de
© Fraunhofer IFAM
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F R A U N H O F E R I N S T I T U T E F O R M A N U FA c T U R I N g T E c H N O l O g y A N d A d vA N c E d M AT E R I A l S I FA M
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Microwave curing
The incorporation of microwave-absorbing
nanoparticles into adhesives allows subse-
quent targeted heating of the adhesive in
the joint area. The electromagnetic radia-
tion is converted by the particles into heat
and passed to the surrounding adhesive
matrix. The curing process can be carried
out at a specific location in a microwave
oven or by emitting the microwaves from
an antenna that is mounted on a mobile
robot.
For research purposes Fraunhofer IFAM
has a microwave oven (Figure 1+3) and an
antenna geometry with defined microwave
fields for qualifying materials and for initial
qualification of the process. In each case
power control is carried out contact-free by
measuring the substrate temperature.
Advantages | Significantly shorter curing time | Selective heating of the adhesive
Bonding of heat-sensitive components
Energy-saving| Versatile use
Fixed location: Microwave oven
Mobile: Antenna, e. g. on a robot| Can be used for components of very
different size
from microsystems to thick-film bonds
Induction curing
For components made of metal and
carbon fiber reinforced plastics (CFRPs),
rapid substrate heating is achieved via
induction-induced eddy currents. Specific
heating of the adhesive can also be realized
by customized formulation of the polymer.
Advanced power control allows a defined
temperature profile, adapted to the pro-
cess, to be set.
The induction unit of the Fraunhofer IFAM
not only allows feasibility studies to be
carried out tailored to your specific pro-
duction-technical requirements but also
allows the initial process parameters to be
determined.
4 Saw blade for cutting stone with adhesive
bonded cutting segments – adhesive curing
via induction.
5 Car headlight with bonded front glass
– adhesive curing via microwaves.
Adhesive curing via
Mikrowaves Induction UV Oven
Shorter curing time ++ ++ ++ –
Selective adhesive curing ++ ++ ++ –
Bonding of heat-sensitive components ++ (+) ++ –
Energy-saving ++ ++ ++ –
Adhesives with fillers ++ ++ (+) ++
Component of very different size ++ ++ ++ –
Versatile use ++ ++ ++ –
++ suitable | (+) suitable in some cases | – not suitable
Advantages | Significantly shorter curing time | Targeted local heating
Rapid heating of the substrates in
milliseconds
Energy-saving | Specific substrate or adhesive heating | Versatile use – fixed location or mobile | Can be used for components of very
different size
comparison of curing processes for adhesives