Composite Materials



Introduction to composite materials
• History of composites in Automobiles
•Why Composites ?
• Effect of Composites on vehicle – Properties & Performance
• Advantages of Composites in Styling & Part Consolidation
• Effect on Safety & Crashworthiness
• Scope on Modern Auto Industries
• Examples of using composites in Modern Auto Industries
• Challenges of building a complete composite car
• Future
What is a composite ?
• A composite material is a homogeneous mixture created by the synthetic
assembly of two materials of which one is a reinforcing material called
fiber and other is the binding material called matrix.
• It is used in all the fields like Automotive, Aerospace, Construction
Industry and Entertainment industry etc
Characteristics
• Rigid – High Strength to weight ratio
• Good Electrical resistance
• Resistance to chemical and weather is high
• Good stiffness
• Good Corrosion resistance


Why Composites ?
• To improve the fuel efficiency by reducing the mass
(Improves straight-line acceleration and top speed, lowering weight offers
these benefits as well as improving handling characteristics (especially
around curves).
• To improve the safety and crashworthiness
• To enhance styling and part consolidation
• To provide the aerodynamic design
• increase horsepower or decrease mass. This
results in a higher power-to-weight ratio, a key
predictor of vehicle performance. While raising
horsepower alone improves straight-line
acceleration and top speed, lowering weight
offers these benefits as well as improving
handling characteristics (especially around
curves). Less weight also reduces loads on the
braking and suspension systems, permitting
engineers to take additional weight out of these
components.
To improve the fuel efficiency by reducing the mass
• Automobile – 5-7 $ /KG
• Aeronautical –500- 700 $ / KG
• Space – 5000 to 7000$ /KG.
To improve the safety and crashworthiness
•Maintain occupant survivable volume or occupant
space.
•Restrain occupants (within that space)
• Limit occupants deceleration within tolerable levels
• Retain “ safety- cage “integrity
• Minimize post crash hazards
To improve the safety and crashworthiness
The specific energy of absorption is given by
S.EA == W /V ρ
Where W --- Total Energy absorption = Area
under curve
V --- Volume of crushed material
ρ --- Density of the material
Safety effect by using composites
• Reduces damage and injury to the passenger
from accidents.
• Composite C –fiber composites are preferable
over steel/ magnesium or aluminium as they
exhibit higher energy absorption values.
• These structure members are in the form of
tubular beams and can be made from glass fiber
and carbon fiber for more critical components.