Group Members

Muhammad Sajjad BSME 01113138Tanzeel-ur-Rehman BSME 01113007Ali Raza Akhtar BSME 01113076Hafiz M. Usman BSME 01113057

Carbon Fiber

What is Carbon Fiber?

Carbon Fiber

Carbon fiber is defined as a fiber containing at least 92 wt % carbon, while the fiber containing at least 99 wt % carbon is usually called a graphite fiber. It is a material consisting of several fibers and composed mostly of carbon atoms. Each fiber is about 5 – 10 μm thick in diameter.

Carbon Fiber

o The crystal alignment gives the fiber high

strength- to-volume ratio.

o Carbon fibers are usually combined with other

materials to form a composite.

o When combined with a plastic resin and wound

or molded it forms carbon fiber reinforced plastic.

Carbon Fiber

o Carbon Fiber Reinforced Plastic has a very

high strength-to-weight ratio, and is extremely

rigid and brittle.

o Carbon Fibers are also composed with other

materials, such as with graphite to form carbon-

carbon composites, which have a very high heat

tolerance.

History

o Carbon fibers were developed in the 1950s as a

reinforcement for high-temperature molded plastic

components on missiles.

o Firstly manufactured by Dr. Roger Bacon.

o The first fibers were manufactured by heating strands

of rayon until they carbonized.

History

This process proved to be inefficient, as the

resulting fibers contained only about 20% carbon

and had low strength and stiffness properties.

Carbon Fiber Vs Steel

Carbon Fiber is actually 5 times stronger than steel. It is also 2 times more stiff. This material has a really very strength-to-weight ratio, which makes it great for almost anything that requires high strength and low weight.

Manufacturing ChallengesThe manufacturing of carbon fibers carries

a number of challenges, including: The need for more cost effective recovery and

repair. Close control required to ensure consistent

quality. Health and safety issues Skin irritation Breathing irritation.

Manufacturing of Carbon Fibers

Carbon fiber is currently produced in relatively limited quantities mostly via two manufacturing processes:

Based on pitch (coal tar and petroleum products) Based on Polyacrylonitrile (PAN)o Current global capacity for pitch-based carbon fiber is

estimated at about 3,500 metric tons per year. Global use for PAN-based carbon fiber is increasing rapidly,

and total production capacity currently does not meet the demand.

PAN-based carbon fiber is more expensive to produce, hence, limiting its use to high end applications, (used primarily by aerospace and sporting equipment industries).

Manufacturing Process In the manufacturing process, the raw material,

which is called precursor, is drawn into long strands or fibers. The fibers are woven into fabric or combined with other materials that are molded into desired shapes and sizes.

There are typically five segments in the manufacturing of carbon fibers from the PAN process. These are:1)Spinning:

PAN mixed with other ingredients and spun into fibers, which are washed and stretched.

Stabilizing:

Chemical alteration to stabilize bonding.

Carbonizing:Stabilized fibers heated to very high

temperature forming tightly bonded carbon

crystals.

Treating the Surface: Surface of fibers oxidized to improve bonding

properties.

Sizing: Fibers are coated and wound onto bobbins,

which are loaded onto spinning machines that twist the fibers into different size yarns. Instead of being woven into fabrics, fibers may be formed into composites. To form composite materials, heat, pressure, or a vacuum binds fibers together with a plastic polymer.

Manufacturing process

Structure

The atomic structure of carbon fiber is similar to

that of graphite, consisting of sheets of

carbon atoms arranged in a regular hexagonal

pattern.

Graphite is a crystalline material in which the sheets

are stacked parallel to one another in regular

fashion.

o A 6 m diameter carbon filament compared to a μhuman hair.

Properties

High tensile strength.

Low thermal expansion.

Electrically and thermally conductive.

Light weight and low density.

High abrasion and wear resistance.

Advantages

It has the greatest compressive strength of all

reinforcing materials.

Long service life.

Low coefficient of thermal expansion.

Its density is much lower than the density of steel.

Exhibit properties better than any other metal.

Insensitive to temperature changes

Disadvantages

The main disadvantage of carbon fiber is its cost.

This fiber will cause some forms of cancer of the

lungs.

Applications

Aerospace and Aircraft Industry.

Sports equipments.

Automotive parts.

Acoustics.

Civil Engineering.

Applications

Portable power. Rechargeable batteries and fuel cell

electrodes. Fiber reinforced plastics, FRP. Energy production; windmill blades. Building and construction materials.

Applications

Air Craft Car Parts

Applications

Musical Instruments

Mobile Case

Applications

Wind Turbine Blades Helmets

Fabric made of woven carbon filaments.

Carbon Fiber’s Future The future efforts on carbon fiber research

will be focused on cost reduction and property improvement.

The mechanical property of carbon fiber heavily relies on its microstructure.

The improvement on the tensile, flexural, and shear strength of pitch carbon fibers has been observed by randomizing the graphite distribution in the fiber transverse direction.

Carbon Fiber’s Future

Alternate Energy:

Wind turbines, compressed natural gas storage and

transportation fuel cells.

Fuel Efficient Automobiles:

Moving towards large production series cars.

Carbon Fiber’s Future

Construction Infrastructure:

Light weight pre-cast concrete, earthquake

protection.

Oil Exploration:

Deep sea drilling platforms, choke and drill

pipes.

Conclusion

It revolutionized the field of light weight

materials.

The new substitute for metals.

In short it is the future manufacturing

material.

ThAnK Y0U

Any Question???