Materials Testing
nano-additive thermoplastic polymer and
the carbon fiber fabric had remarkable
characteristics. This recommends them as
potential solutions for structural materials
in aerospace. The laminates obtained have
a low specific weight combined with high
flexural and tensile strengths and they can
be easily used on the elements inside the
planes, increasing the safety of the
passengers and at the same time
contributing to the reduction of the
aircraft’s weight. The recycling possibilities
of thermoplastic materials (superior in
nature to epoxy composites) allow for the
reuse of the matrix when the component
reaches the end of its life-cycle. This topic
of recycling is sensitive in the aerospace
industry.
FIBER SURFACE MODIFICATION
The adhesion of the polymeric matrix to
the interface of the fibrous material
significantly affects the properties of the
hybrid composite system. The existence of
functional groups on the surface of the
3
involves low cost and low energetic
consumption. The obtaining methods also
involves solution dispersion, which ensures
optimum homogenisation of the
nanometric agent in the polymeric matrix.
The nanofilled matrix is processed at room
temperature, without the use of additional
compounds and the solution impregnation
of the carbon fiber fabric allows quality
enhancement through optimum use of the
raw materials, with insignificant materials
loss. In addition, the obtaining method
allows the development of hybrid
composites, such as laminated
nanocomposites, based on carbon fiber
fabric with high mechanical properties.
Another advantage is that the hybrid
nanocomposites systems with nanofiller
addition exhibits mechanical strength that
is 30-45% higher and elasticity modulus
that are 40-70% than those of the
materials with no nanofillers.
Both the polymer-based laminates and
carbon fiber layers as well as the
nanocomposite laminates based on the
AEROSPACETESTINGINTERNATIONAL.COM // SHOWCASE 2020 53
with a weaker impregnation, initially
proven by the behavior at the time of
cutting (the tendency to detach the layers)
showed the smaller mode and breaks in
different directions at smaller efforts.
The structural composite revealed an
increase in tensile strength compared to
the control sample. In the case of
resistance and flexural modulus the values
revealed by the additive laminates were
higher than the non-additive and
reinforced with fiber fabric.
The thermal stability tests performed on
the composites based on the thermoplastic
resin revealed that the modification of the
matrix can influence the deflection
temperature. In the case of laminates with
simple reinforced matrix, the HDT (heat
deflection temperature) test shows an
increase of about 5°C, an insignificant
amount. Modification of the thermoplastic
matrix resin up to 4% by nano-additive can
improve HDT temperature to about 25°C.
Advantages of the technology are that
the obtaining method is simple and
1 // SEM micrograph of
breaking area
2 // Optical micrograph on
the tested thermoplastic
composite laminate
3 & 4 // Breaking area of
unfilled composites system
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