Composite materials have been used in automotive exteriors since the 1930s. They provide benefits like reduced weight, improved strength and design flexibility. Sports cars extensively use carbon fiber composites for their exteriors due to requirements for high strength and stiffness. Composite materials are also used in truck and trailer body panels. While composites provide advantages, challenges remain around manufacturing volumes, repairs and supply chain development.

2. COMPOSITE MATERIALS FOR
AUTOMOTIVE EXTERIORS
BY
Muhammad Sohail Aunjam
18-NTU-MSTE-6009

3. What Is Composite?
“The synthetic and engineered assembly of two divergent materials;
a reinforcement the fibers and a binding material the matrix is
known as a composite material.”

4. Automotive Industry
“The corporations and actions involved in manufacturing of motor
vehicles including bodies and engines but excluding fuels, batteries
and tires are categorized in automotive industries.”

5. Automotive Industry Raw Materials
• Automotive industries use a wide range of raw
materials including;
1) Iron
2) Steel
3) Aluminum
4) Rubber
5) Petroleum Products

6. Composites In Automotive Industry
• Gradual improvements, alternatives to fulfill gaps, inventions and
modern requirements drive automotive industry towards the use
of composite materials.
• All three types of composites based on matrix type; MMC, PMC
and CMC are used in automobiles depending upon the desired
properties and performance parameters.

7. History
• The use of composites in automotive industry is not credited to
21st century but such materials have been used in automobile
industry from 2nd quarter of the 20th century, since 1930.
• 1930: Henry ford produced phenolic resin from soya oil to
construct a wood filled car body.
• 1940: Flax reinforced spitfire fuselage was made at Duxford.

8. History
• 1950: Curved streamlined automotive bodies developed from
glass fiber as reinforcement and cold setting polymers as matrix.
• 1954: First time in bulk volumes used by Singer Hunter for glass
fiber reinforced car bonnets and side valences.
• 1960: Lotus Elite & Reliant Scimitar used hand laid glass fiber
composites.

9. History
• 1980: Pontiac Fiero becomes the first car with composite
intensive body.
• 1990: Rover Group start research on composites and later on
changes into BMW phase, the fastest cars era.
• 21st Century: Large scale automobile manufacturers like
Volkswagen, Ford, Toyota, Mercedes Benz, other Chinese and
Japanese companies start using composites.

10. Why Composites?
• Reduce fuel consumption by reducing mass of the vehicle.
• Enhance safety measures and crashworthiness.
• Improve styling, designing and consolidation of automotive parts.
• Adapt aerodynamic design to reduce drag and frictional forces.
• Higher strength to weight and stiffness to weight ratios.
• Ease of design and molding complex parts.

11. Automotive Exteriors

12. Composites In Automotive Exteriors
• The innovations and desire to achieve better properties led the use of
composite materials in manufacturing of automotive bodies and
exterior components incorporated with light weight, high strength and
metal comparable properties.
• Composites are not much widespread in this industry due to some
critical limitations like technical issues in manufacturing, coupling with
other materials, accuracy in part dimensions, issues in repair and
unavailability of data and information regarding safety standards.

13. Chevrolet Corvette Body
• In June 1953, Corvette becomes the first production car with a
body made up of fiberglass.
• This exterior trim was achieved by using Vacuum assisted wet lay
up technique.

14. Citroen XM Front End Panel
• In 1987, first time the front end of a car Citroen XM was
manufactured from sheet molding compound, replaced a number
of steel panels from the front end of Peugeot 405 and Citroen
XM.

15. Renault Tail Doors
• Tail doors and a number of outer panels of a number of models
from Citroen like BX, Xantia, ZX and AX, Rigata, Tipo and
Renault escape are manufactured from sheet molding
composites.

16. Camaro And Firebird Side Doors
• Sheet molding composites and fiber reinforced thermoplastics have
been used in side doors of Camaro, Firebird, GM’s and Corvette.
• It reduced the weight of each door about 5kg in comparison to steel
frames.
• Renault Escape, Pontiac Fiero, Mazda AZ-1 and BMW Z1 also use
SMC injection molded composite outer panels.

17. Thermoplastic Polymer Composites
• Glass fiber reinforced polypropylene composite replaced cast
aluminum frame in Volvo V70. And reduced the weight by 27%
and its cycle time is also less than 4 minutes.

18. Thermoplastic Polymer Composites
• Thermoplastic polymer is also used in manufacturing of BMW M3
bumper beam. It is purely made up of composite and reduce the
bumper weight by 60% with improved energy absorption levels.

19. Thermoplastic Polymer Composites
Thermoplastic resins used as matrix in such applications are listed
below;
▪ Polyethylene
▪ Polypropylene
▪ Polyvinylidene Chloride
▪ ABS + Styrene
▪ Polyamides
▪ PBT + PET
▪ PMMA
▪ PC
▪ POM
▪ PPE

20. Thermoset Polymer Composites
• These are mostly used in exterior parts manufacturing. Resin
transfer molding (RTM) and sheet molding compound (SMC) are
the methods to manufacture automotive parts in medium to
higher volumes.
• Polymers used as matrix in these applications are UP resins,
PUR and some other thermoset polymers.

21. Thermoset Polymer Composites
• Renault escape is one of the best examples pf using these
techniques as it featured with polyester SMC body panels and
tailgates engineered with RTM.
• SMC tailgates also made in to the Volvo V70.

22. Composites In Sports Cars Exteriors
• High speeds, high strength to weight ratios, high stiffness to
weight ratios, low production volumes and lead class affordability
for higher costs make it possible to use composites extensively in
this category of automobiles.

23. Composites In Sports Cars Exteriors
• The most desired property of racing cars is high impact
resistance at high speed crashes and carbon fiber reinforced
composites promise such characteristics with much lighter weight
and high energy absorption levels than metals.

24. Composites In Sports Cars Exteriors
• The Mercedes-Benz McLaren SLR and Porsche Carrera GT
body structures made up from carbon fiber reinforced
composites.

25. Composites In Sports Cars Exteriors
• The structural skin of the Aston Martin Vanquish V12 is also
made up from carbon fiber bonded to an extruded aluminum
substructure.
• Its front and rear glass structures are also reinforced by polyester
by means of resin transfer molding to protect against crashes and
avoid glass cracks propagation.

26. Composites In Sports Cars Exteriors
• The Dodge Viper is also accompanied by glass fiber reinforced
composite wings synthesized through reaction injection molding.
Bonnet is made up from glass reinforced sheet molding
compound and wing supports, windscreen frame and door panels
are made up from carbon reinforced SMC.

27. Composites In Sports Cars Exteriors
• Ferrari Enzo has provided the most intensive use of carbon fiber
reinforced composites. Its complete body and chassis are made
up from carbon fiber reinforcements.

28. Composites In Trucks And Trailers
• Trucks, trollies and lorries are a divergent field of application in
context to automobile industry, but these are also automotive
products made up to transport heavy items from one place to
other. The purpose is to build powerful vehicles to transport
goods and luggage.

29. Composites In Trucks And Trailers
• Kenworth T2000 is a truck capable to produce up to 600
horsepower and transport heavy materials. The bumpers,
brackets, step fenders and roof caps of this powerful lorry are
made up from glass fiber reinforced SMC.

30. Composites In Trucks And Trailers
• The Ford Aeromax 9500 is also accompanied by glass reinforced
SMC door panels, bumper, bonnet and roof cap with the purpose
to reduce weight and utilize its more power in transportation The
total composite used in manufacturing of this truck weighs around
204 kg.

31. Natural Fiber Composites
• Natural fiber composites are inferior to glass and carbon fiber
reinforced composites. So, they are also used in automotive
where high mechanical performance is not the requirement.
• Door panels and rear trunk upper hoods are the major
applications of natural fiber reinforced composites in context to
automotive exteriors.

32. Natural Fiber Composites
• Hemp reinforced composites are used in body panels and
spoilers of Eco Elise car. Its hemp reinforcement is also
incorporated with solar panels to produce electricity from solar
energy and provide power to electrical systems of car.

33. Natural Fiber Composites
• This one has a unique identification in automotive industry with
the tag line of green composites car. Its complete exterior
structure is manufactured from flax reinforced composites while
its structure elements have also used recycled carbon to make it
an eco-friendly car.

34. Carbon Fiber Composites
• Carbon fibers an reduce mass of a vehicle in huge numbers in
contrast to comparable metals.
High
Strength &
Stiffness
Low Density
Lightweight
Automobiles

35. Carbon Fiber Composites
• The latest BMW models i3 and i8 are tagged with a slogan
“Harder Than Steel” are made up from carbon fiber composites.
Its underbody is completely made up of CFC composite.

36. Carbon Fiber Composites
• The Volvo cars international is developing car body panels from
carbon fiber reinforcement and polymer resin as matrix, which
has built-in capability to store and discharge electrical energy.

37. Carbon Fiber Wheels
• Japanese company Weds Sport manufacture dry carbon fiber
wheel first time in 2008 and this one promised the great
performance and life cycle with only 2.76kg weight.

38. Technology Innovations
• In the latest model of Lamborgini a new tagline has been
introduced named the carbon skin.
• This concept has exhibited the extensive use of woven carbon
fibers soaked in special epoxy resin that also stabilize the
structure and still retains the material softness.

39. Technology Innovations
• The latest Toyota Lexus LFA is made up of 65% carbon fibers
and 35% aluminum of its total weight.
• It used the 3D weaving technique that reduced the required
material volume by 50% and enhance the mechanical strength
parameters.

40. Technology Innovations
• This one is really a new and creative concept. This tiny car
weighs around 942ks and featured with extra-thin carbon fiber
doors and panels. Its interiors are also developed from natural
fiber composites.

41. Current Problems
Some major constraints in use of composite materials in automotive
exteriors are;
▪ Robust supply chain
▪ Design of energy absorption
▪ Fit and finish
▪ Volume manufacture
▪ Design complexity
▪ Tooling assumptions
▪ Capability for computer aided designing
▪ Component quality
▪ Risk assessment
▪ Performance feel
▪ Repairs and maintenance

42. Conclusion
It is concluded that composite materials have a great potential in
automobiles and automotive industry is shifting rapidly from metals
to composites but with some limitations and researches. Carbon
fiber reinforcements and latest technological developments like
forged composites concept has outclass the conventional materials
and metals.