Why Composites?
Benefits
Composites can be used:
When high stiffness or strength-to-weight ratios
are desired.
When high fatigue strength, corrosion resistance,
resistance to fracture, impact, and creep resistance are required.
Under harsh environmental conditions due to their
low thermal and hygric coefficients of expansion.
The high stiffness and strength-to-weight ratio makes composites appealing
for use in a wide variety of applications. For example, composites are
used in airplanes mainly for overall mass reduction. The initial material
costs are high but there is a significant reduction in fuel cost during
operation.
Their low thermal coefficient of expansion for example, make them attractive
for use in satellites in space where huge temperature changes occur.
Applications
Composites are utilized in many applications ranging from aircraft and
automobile parts to bio-medical implants and recreational products. Some
examples are listed below:
Aircraft components - Engine cowlings, outer wing,
belly fairing skins, nose landing gear doors, and tail cone among others.
Space shuttle components- Sleeves, vent lines,
and fuselages.
Helicopters - Rotor craft blades (graphite-epoxy
composites).
Automobiles - Bodies made of carbon fiber composites
or fiberglass composites.
Boats - Hulls (wood or Kevlar).
Bio-medical industry - Implant materials.
Recreational products - Bicycle frames, rackets,
skis, and golf club shafts.
Limitations
Difficulty
of damage (intra-ply and inter-ply) detection. This requires expensive
non-destructive evaluation techniques or structural health monitoring
systems
Difficulty
in determining material constants as they are usually orthotropic.
Low
fracture toughness for same strengths compared to metals.
Related Topics
Composite
Shells
Stacking
Sequence of Plies
Ply Angle
Adjusting Composite
Orientation Options
Composite Failure
Criteria