JEC COMPOSITES MAGAZINE - Issue #131 - Novembre/December 2019 - 38

FEATURE
cycle times

Fast-curing epoxy prepreg system for
automated processes with short cycle times

Daniel Grauer,
Head of Technical Sales
Steffen Perner
Senior Sales Account Manager
C-m-p gmbh

he aerospace industry is the world's
largest user of carbon fibre-reinforced plastics (CFRP). The
automotive industry ranks second, both in
terms of volume (37,000 metric tons) and
sales (4.17 million US dollars). In 2018,
the automotive industry thus accounted
for about a quarter of global demand,
2% more than in the previous year. The
advantages of CFRP vehicle structural
components have long been known. One
challenge for CFRP manufacturers is to
significantly improve the cost-effectiveness of production processes, especially
since the added value in the automotive
industry is lower than in the aerospace
industry due to the advantages of lightweight construction. Nevertheless, its
importance in vehicle construction is also
increasing every year.
Only advanced preform and prepreg technology can achieve the profitability and
cost targets required for mass production.
New development approaches such as
the modified CP012 epoxy resin system
from c-m-p gmbh (Heinsberg, Germany)
are taking an upswing here. The company
developed it mainly for the prepreg pressing process in the automotive industry
(e.g. for the lamp pot and lamp holder of
the Porsche GT3), but it is also suitable
for other industrial applications. The
sports and leisure sector (cross-country

Until now, series production of CFRP components in the automotive industry has failed due to excessively long process times and
high costs. A new, fast-curing epoxy resin system now makes
structural and visible components in vehicle construction ready
for series production.

and alpine skiing), for example, has great
market potential. Other areas of application for the technology include aerospace,
defence, mechanical engineering and
industrial components.
Founded in 2011, c-m-p gmbh specialises
in the manufacture of tailor-made prepregs and textiles from carbon and other
high-performance fibres. A global technology leader in the industrial production of
pre-impregnated fibres and fabrics up to
two metres wide, the company is known
for its innovative solutions for lightweight
construction and design. Companies in
many industries around the world rely on
these high-quality and application-oriented products.
CFRP for the mobility of the future
Lightweight construction supports the automotive industry in reducing greenhouse
gas emissions as required by law without
having to fundamentally change the vehicles. In addition, this technology increases
the range of electric vehicles. These are the
main reasons why all major manufacturers
are looking for ways to replace their standard materials with lightweight composite
materials. Every kilo counts for both
e-mobility and conventional vehicles: a
weight reduction of 100 kg reduces fuel
consumption by 0.4 l per 100 km driven
and means about 10 g less CO2 emissions.
Carbon fibres as reinforcing components
offer the greatest potential here.

jec composites magazine / N°131 November - December 2019

Series production
requires short cycle times
The requirements of the automotive industry are clearly defined: composite materials suitable for series production must
have short production cycles and consistent quality so that body components such
as doors, roof modules or tailgates, as well
as structural components such as columns
or underbodies, can be produced quickly
and cost-effectively and thus ready for
mass production. These criteria were also
fundamental for c-m-p gmbh in order to
be able to map automated processes for
the large-scale use of CFRP. The greatest
challenge was to achieve a new resin formulation that ensured a very low viscosity
could be maintained for a sufficiently long
time. With the CP012, the company developed a resin that has a good thermal latency and thus enables a delayed reaction.
This is critical for proper impregnation at
high temperatures and short time cycles,
accompanied by rapid curing of the resin
when the specific temperature is reached.
Main characteristics of
the modified epoxy resin system
The curing time of the CP012 system varies between 3 and 15 minutes depending
on the temperature. The typical processing window is between 120 and 180°C.
Depending on the curing temperature,
a glass transition temperature (Tg) of up
to 135°C is possible, which corresponds
to most automotive standards for further

JEC COMPOSITES MAGAZINE - Issue #131 - Novembre/December 2019

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #131 - Novembre/December 2019