Racecar Engineering – September 2019

(Joyce) #1

86 http://www.racecar-engineering.com SEPTEMBER 2019


TECHNOLOGY – COMPOSITES


intrinsic properties of the fibres,’ says Fischer.
‘These properties mean it does not make
sense to build a chassis out of natural fibres,
because carbon fibre sandwich composites
are so effective. We focus on thin-shelled
parts, typically monolythic single-skin or thin
sandwich applications up to 2mm thick for
which our solution provides the equivalent
stiffness of a sandwich core.
‘Where we see significant potential is in the
non-critical, semi-structural areas of a racecar,
such as the bodywork,’ Fischer adds.
For certain applications, AmpliTex and
PowerRibs can also be combined with carbon
skins to create a hybrid structure which then
outperforms pure carbon fibre whilst achieving
a weight saving of up to 25 per cent.

Laying up
The manufacturing processes that use AmpliTex
and PowerRibs are similar to those of carbon
fibre, if not easier. When using prepregs, a layer
of fabric pre-impregnated with pre-cured resin,
ubiquitous to composite manufacturing, the
PowerRibs can simply be added dry on top of
the laminate, and the processing pressure will
drive the liquid resin from the substrate for
complete impregnation. In vacuum infusion
the dry PowerRibs act as their own flow media
to help with the infusion of larger surfaces,
removing the need for ad hoc, wasteful
consumables such as those commonly used in
carbon fibre manufacturing.
The first racecar that featured Bcomp
materials was the Electric GT Tesla P100DL,
which has bodywork made from AmpliTex
and PowerRibs that has helped to achieve a
500kg weight saving compared to the road
car version. There was also a full-natural fibre
bodied car, the Gillet Vertigo, which raced up
Pikes Peak in under 11 minutes in 2018.

Splinter resistant
To compete in high level motorsport, materials
have to pass the FIA crash safety tests, and this
is another advantage of the Bcomp products.
The nature of flax fibres, with the structure of
PowerRibs, means that these composites do
not splinter like carbon, which can causes all
sorts of issues on track such as tyre punctures.
‘During the drop tower tests where a 2.2kg steel
ball is dropped from two metres, the carbon
composite plate shatters, generating sharp
debris,’ says Fischer. ‘Whereas the composite of
AmpliTex and PowerRibs is not as fragile, and
while it still breaks, the softer debris remains
attached to the main structure with the help of
the PowerRibs, which help dissipate the energy.
Therefore, flax composites can, in a sense,
be deemed ‘safer’ than carbon fibre. This has

‘I want our materials to be fitted on to the rear wings of racecars,


because this will show the world that this is tomorrow’s tech’


caughttheeyeofGTracepromoterSROand
it is nowintheregulationsthatanyGT4cars
homologatedafterJanuary 2019 mustfeature
bio-basedcompositeswithintheaeropackage,
withsyntheticfoamcoresbanned.
AsBcomp’smaterialscontinueto
integrateintothemotorsportsector,itsalso
implementinglight-weightingsolutionsinto
roadcarsaswell.Naturalfibrecompositesare
nowusedinsomeinteriorpanels,withtheuse
ofPowerRibsreducingweightbyaround 40 per
centaswellasreducingtheuseofplasticsby
80 percent,whencomparedtoa standard
injectionmouldedpanel.
‘Peoplesometimessay:“Christian,you’re
buildingthisgreentechstory,butthenyou

gointomotorsports”andI say“Yes,because
motorsportis stilltheplatformoftomorrow’s
technologies”,’Fischersays.‘I believethat
wheneveryoucanplayintheChampions
League,thenyougoplayintheChampions
League.SoI wantourmaterialstobeonthe
rearwingsofracecars,becausethiswillshow
theworldthatthisis tomorrow’stech.’
‘Butcustomersshouldn’thavetopaya
premiumforgoinggreen,’Fischeradds.‘You
buyanorganicapplebecauseit’sgoodfor
youandyourconsciencebutif it doesn’ttaste
good,you’renotgoingtobuyit anymore.Thisis
whyourmaterialshavetoout-performcarbon
andglassfibre,whichis whatAmpliTexand
PowerRibsallowsustoachieve.’

The Gillet Vertigo, a full-natural fibre bodied racecar, competed at Pikes Peak last year, getting to the top in under 11 minutes

A natural fibre composite door panel for a VLN Porsche; these materials are best suited to semi-structural areas on the car
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