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allied
academies
Materials-Metals 2017
Page 19
November 16-17, 2017 Paris, France
13
th
Annual Conference on
Materials Science, Metal and Manufacturing
Journal of Materials Science and Nanotechnology
Volume 1 Issue 2
Mikko Kanerva at al., Mater Sci Nanotechnol 2017, 1:2
Build-up of new nature-mimicking materials using
automated simulation routines—the future trend?
Mikko Kanerva, Sanna Siljander
and
Jarno Jokinen
Tampere University of Technology, Finland
T
he current consumption of fossil fuel resources and respective
production of traditional polyolefin plastics has led to huge
clustering of plastics in oceans as well as in landfill sites. In
its simplicity, sole recycling will never solve the waste problems
because plastics will anyway be left unrecycled at a finite rate
due to the human nature. Biodegradable, isotropic polymer
blends are neither a complete solution for all applications
because their performance is far behind that of current high-
performance polymers, such as the ones of epoxy, vinylester,
aramid, and bismaleimide thermoset families. Basically all the
biodegradable polymeric systems for structural applications
are continuous fibre-reinforced plastics. In these composites,
either the reinforcement (e.g. bio-based fibres) or the
polymer matrix is the degradable component. The reinforcing
particles can have various forms and involve wood particles
and fibres, natural fibres (e.g. flax or hemp), clay, starch, and
cellulose. For high performance applications, the outcome
of these studies boils down to the fact that there is always a
distinctive compromise between a high bio-particle content and
good mechanical properties, or, in other words, the composites
represent a double-edged sword with some sustainability and
mechanical performance. However, a carefully adjusted mixture
of synthetic and natural fibres can result in a better mechanical
response, e.g. against impact loads, compared to composites
with only either type of reinforcement. Graphite as well as
carbon nanotubes have excellent electrical, mechanical and
thermal properties. For these reasons they are considered
to be used in many types of composites in the future.
Combining CNTs with cellulose has known to be eco-friendly,
efficient, low cost and non-metal based option. Applications of
CNT/cellulose composites usage are reported to be in the fields of
electromagnetic interference shielding, chemical vapour sensors
and in pressure sensing. Also, totally new species of advanced
’nat- ural’ materials are being developed. For example, the
nacre-mimetic materials are a type of nano-composite that
significantly benefits the synergetic arrangement of its rather
unique poly(vinyl alcohol)/clay building blocks. The maturity
of these materials is on a laboratory level and will take long until
their processing can reach commercial needs. Eventually, any
environment degrades the material properties of polymeric
systems. In order to create new high-performance composites,
the degradation behavior must be understood and controlled.
Especially the fibrous composite materials are challenging to
analyse considering the aging response. Even pure linear
anisotropic models will require nine engineering constants per
material not to mention the interface models to tie different
layers together, or the internal residual stress models.The
question from the numerical analysis point of view is how to
define relevant parameters when modelling the environmental
effects of laminate or an entire structure. This presentation will
deal with the application of automated simulation routines
to design new materials. Ex- amples of using Abaqus-Isight
(Simulia) coupling are presented for understanding the aging in
high-performance glass-fibre reinforced composites (Fig. 1(a)).
The focus in these cases are on the challenges of building up the
material model for a layered composite with correct interface
models. In the second part of the presentation, examples of
new materials with optimized nano-strengthening are presented
(Fig. 1(b)). Film preparation using nanofibrillated cellulose,
CNTs as well as electrospinning are described with emphasis
on the sonication models, particle-ratios and de-hydration. The
presentation will discuss the future trends in using autonomous
and smart numerical simulations to screenmost potential multi-
composites for optimized behavior in specific applications.