JEC COMPOSITES MAGAZINE - Issue #82 - July 2013 - 42

wishbone

Fig. 5: Tool picture and sketches

ality, as the automotive industry requires
reliable simulation tools.

High production rates for cost
optimisation:
the project is taking shape

Fig. 6: Overmoulding the pivot joint

the plate on the ball joint end is covered
on both sides. This solution limits the
risks of offset attachment points and
improves the assembly’s durability.

Concept validation –
Simulation control

As described above, CETIM and ONERA teamed up to design a wishbone
arm complying with PSA’s mechanical
specifications while reducing weight by
50% as compared with a steel solution.
The process developed for this study can
also achieve production rates compatible
with the automotive sector. Raw material
costs still prevent the use of composites
for consumer products in the automotive
industry. The significant cost of semiproducts such as prepreg plates results
from the high number of upstream operations (weaving, impregnation, consolidation, etc.), to which should be added

material losses when cutting the semiproducts to obtain, e.g., the required fibre
orientation. To overcome these problems,
CETIM is leading a platform dedicated
to composite part manufacturing at high
production rates within the framework of
the Jules Verne Technological Research
Institute in Nantes, France, in behalf
of the French transportation industry.
The production line will include several
modules including thermoplastic projection and Resin Transfer Molding (RTM),
and an innovative patching process (see
Table 1). The latter is of most interest to
the partners for the wishbone arm. The
principle of this line is to avoid as many
semi products as possible and be able to
position the fibres precisely where they
are needed. The partners consider that
the best solution is to use pultruded tapes
with variable thickness and width and
then cut these tapes as required (while
ensuring minimum material scrap) to
make a preform. The preform is defined
using a numerical tool which optimises
fibre positioning with respect to mechanical stresses. The preform is then heated
before final manufacturing by thermocompression. By limiting the number of
semi-products and minimising material
scrap, this line will make it possible to
manufacture structural parts using highperformance composites at acceptable
costs for the automotive industry. n
More information:
sqr@cetim.fr
www.cetim.fr
Christian.fagiano@onera.fr
www.onera.fr

Mechanical characterisation tests are in
progress to refine the calculation model.
Following the tests, the results of the
finite element model will be
Tab. I: Patching/paving/stamping innovative process for low cost/high volume composite pieces
compared to tests performed
on a real part and the damage
Induction heating
Extrusion
Discontinuous
multi-axial and
modes will be analysed, among
+ pultrusion
cutting
multi-material preforming
Thermo-compression
other things. The purpose of this
Pultrusion line
Perform assembling station
phase will be to better understand
the relationship between tests
and calculations in order to evaluate the confidence level of the
www.dewalt.com
simulation results. The modelling
Thermoplastic
process will also be improved so
Specific cutting
Thermoforming press
extrusion
as to be as close as possible to re-

42 jec composites magazine / No82 July 2013

Injection overmoulding

Injection
overmoulding unit

http://www.cetim.fr http://www.onera.fr http://www.dewalt.com

JEC COMPOSITES MAGAZINE - Issue #82 - July 2013

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #82 - July 2013