"Universities and research institutes and producers of coatings and coatings materials in Europe are beginning to commercialize the outcomes of years of R&D into the
biomimetics or mimicking of biological surface structures.
The development phase of a lot of the research has been accelerated by advances in nanotechnology, which have enabled natural processes to be reproduced with the help of
nanoparticles and materials."
particularly since both together have an
important influence on surface energy,”
said Parnia Navabpour, a scientist at UK-based Teer Coatings Ltd., one of 31 industrial and academic partners in AMBIO.
Nonetheless, discovering coating structures for ships hulls which both inhibit the
adhesion of microorganisms and retain
energy efficiency and fuel consumption
levels by leaving the hydrodynamics of the
vessel unimpaired could be a big problem.
An R&D team at Fraunhofer’s Manufacturing Engineering and Applied Materials Research unit (IFAM) at Bremen,
Germany, won one of the institute’s main
research awards this year by developing a
system for applying a coating imitating the
scales on sharkskin, which significantly
raises drag resistance in air and water.
One of the difficulties to be overcome
by the researchers was to find a method
for applying on an industrial scale the
coating on complex three-dimensional
surfaces. “Our solution consisted of not
applying the paint directly but instead
through a stencil,” said Manfred Peschka,
a scientist on the project.
With the help of nanoparticles, the coating withstands on aircraft extreme temperatures, intensive UV radiation and high
speeds. On large container vessels it reduces friction with water by five percent.
But the researchers are still looking for an
anti-fouling solution for ships. One option
they are investigating is structuring the
paint in such a way that the fouling organism cannot gain a firm grip on the surface.
Developers of structured coatings also
see the prospect of using them for improving the aerodynamics of automobiles.
Lower drag levels are already being
achieved with rough coating surfaces on
racing cars and exclusive sports models.
“In devizing super-efficient aerodynam-
ics in cars we can learn a lot from the ani-
mal world from creatures like fish which
don’t have smooth skins,” Frank Stephen-
son, styling director at McLaren Automo-
tive, a UK manufacturer of sports cars, said
at a recent design meeting in London. “The
future with cars could lie with different
coating surfaces than at present.”
In the mass market for automobiles,
however, the big problem is that struc-
tured coating surfaces with higher drag re-
sistance seem at the moment unlikely to
have the same optical appeal as the
smooth surfaces which car owners now
take for granted.
“Structured coatings can be applied to
aircraft without this difficulty,” said
Lothar Schaefer, a research coordinator at
Fraunhofer. “With cars the visual appear-
ance of these coatings may not be what
the customers want, even though with
nanomaterials the structural patterns will
not be apparent to the eye.”
Perhaps the recent introduction of
matt clearcoats with rough surfaces to
give a muted silky finish to certain ex-
clusive automobiles in Europe will lead
to opportunities for combining attractive
optical effects with improved aerody-
namics. CW
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