Carbon/biocomposite hybrid vehicle structures for reduced weight, cost and environmental impact (CARBIO)

Carbon/flax fibre-reinforced hybrid composites offer advantages in terms of vibroacoustic, weight and cost when compared
to conventional steel and aluminium alloys which can be related to minimisation of emissions and fuel consumption.
However, vibro-acoustic characteristics of epoxy-carbon fibres/flax hybrid composites and their co-relation to structural
strength of the composite remain unexplored and a stumbling block in the application of the material technology to
manufacture better components. The increased application of both flax fibres and carbon fibre composites in automotive
components requires proper understand of vibro-acoustic problems and their effects in structural design and
manufacturing. The CARBIO project, therefore, involve investigating the vibro-acoustic levels for selected components
/systems for determination of tuneable frequencies, determination and quantification of vibroacoustic coupling between
temperatures variations, panels architecture and body assembly contributions and noise levels benefit against
benchmarked fully epoxy/carbon fibre, steel and aluminium components.
The study stems from the fact that with increasingly stringent environmental regulations and requirements, noise and
vibration have become very important design considerations for automotive manufacturing. Modern vehicle customers are
aware of their environmental needs and therefore demand the most economical car, the most comfortable to drive and
obviously the cheapest. As a consequence, the automotive industry has become a consumer driven industry where noise,
vibration and environmental harshness has become a measure of design excellence and vehicle performance, a fact
reflected strongly in vehicle sales. A rational approach to reducing noise and vibration is to improve the damping properties
of the materials from which the car parts are manufactured. Currently, body panels are mainly manufactured from steel
and aluminium alloy in conventional vehicles and epoxy - carbon/glass fibre- reinforced composites in high performance
cars. More effective measures for noise and vibration reduction are desirable if the automotive industry is to achieve an
acceptable driving environment and comfort as vehicle structural masses are reduced in response to environmental
demands.
The project acknowledge that hybrid composites with natural fibres are a key solutions to the vibroacoustic problem since
natural fibres (flax) have much higher damping properties. In addition to the reduction of mass, composite materials offer
consistent potential advantages in terms of noise and vibrations reduction, impact resistance, energy absorption capability. They also offer advantages in the manufacturing process, such as cost reduction for producing low volume pieces and the
possibility of integration, i.e. structures which can be made with fewer sub-components. Composites also possess a unique
capability: to be tailored in order to meet design requirements which are ill-matched for conventional materials, by properly
choosing the constituent materials and the orientation of the reinforcement fibres. This is of primary importance for the
performance optimization, the target objective being a minimization of the mass and/or of stress concentrations,
guaranteeing the required performance. Use of thermoplastics and other lightweight materials also aligns UK OEMs with
the end of life vehicle EU directive in that by 2015 , vehicles must be constructed of 95% recyclable materials, with 85%
recoverable through reuse or mechanical recycling and 10% through energy recovery or thermal recycling. It is envisaged
that the proposed project will give the UK automotive industry a leading edge in global industry.

Strategic impacts of the proposed project and direct expected benefits
Quantitative objectives
i) Greener production process: use of less carbon fibre with respect to current levels of production
ii) 25% production cost reduction
iii) 20% higher noise, vibration and harshness (NVH) performance
iv) New knowledge on carbon fibre/flax fibre/epoxy composites structural and damping performance
v) 20% weight reduction on
Qualitative objectives
i) Contribution to better NVH performance from cars.
ii) Overall weight reduction
iii) Reduction of other vehicle emissions (NOx, N2, hydrocarbons etc) in EU air - associated with cleaner environment,
better health and living for EU residents.
iv) Help to develop green initiatives industry in Europe.
v) Introduction of Quality control of industrial process ISO 9001.
vi) To extend these results to other applications in the field of transport (aviation and trains)
vii) Reduction of noise (pedestrian).
viii) Reduction of fuel expenses to UK residents - better fuel efficiency gives 2-3 yrs pay back).
ix) Position of UK/Europe as a leader in key areas of underpinning science and engineering for future low-CO2 vehicles.
x) Increase competitiveness of UK/EU SME and OEM whilst underpinning UK/EU automotive industry in readiness to tap
future income in low carbon vehicles and along with other applications. The upcoming markets are mainly India, China,
Brazil - 600 (India) and 500 (China) million cars on road, respectively, are expected by 2050 - while cementing low carbon
vehicle philosophy.
xi) Training of new blood- young skills at SMEs in low carbon vehicles to prepare for the future needs of the world and to
cater to a healthy local economy.
xii) Contributions to UK/EU low carbon vehicle policies.
xiii) Study and development of new industrial materials applied to the automotive industry, in special to small cars segment
which is growing very fast.
xiv) Introduction of the European regulation on the use of new materials in industry.
Environmental impacts
The manufacturers are faced with the challenge of designing systems and components that have to be safer, more reliable,
cheaper to operate, deliver better passenger comfort and have less environmental impact than their competitors. In
addition, stringent environmental constraints, increased competition and global partnering translate into difficult engineering
challenges and an ever-stronger need for collaborative design and engineering solutions. With the relatively limited resources of the companies an evolving rationale for design and development is required and a significant part of this is in
meeting environmental requirements. Within Europe SMC and BMC are the most important composite materials in terms
of industrial production. Both SMC and BMC have been manufactured with over 300,000 tons in the year 2007. Roughly
one third of this capacity was used in the automotive/ transportation market. If only 30% of this material was replaced by
SMC/ BMC derived from renewable resources, it would have a direct bearing on the ecology in two ways. Firstly, the
impact of CO2 emission on environment would drastically reduce. Additionally the SMC/ BMC coming from renewable
resources would bear lower density. Today's standard SMC has a density of 1,9 g/cm3, whereas SMC from renewable
resources could have a density of 1,4 g/cm3 or lower. This would also help to lower the weight of vehicles and lower their
CO2 emissions. Moreover, the project will narrow the bridge between the engineering and the environmental applications
aiming to encourage 'green' research activities. Reduction of emissions, lightweight construction, freedom in design,
integration of functions and reduction of costs, rank among the most important requirements of the original equipment
manufacturers (OEMs). As a consequence, light weighting is one of the major drivers for the use of composites in the
manufacturing of consumer goods., hence additional benefit