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1. PRESENTATION
on
FIBER MANUFACTURING
 
Presented by:
MUHAMMAD UMAIR BUKHARI
INSTITUTE OF ADVANCED MATERIALS

2. Muhammad Umair Bukhari
Engr.umair.bukhari@gmail.com
www.bzuiam.webs.com
03136050151

3. FIBER
Ж High strength to weight ratio
Ж High stiffness
Ж Corrosion resistant.
Ж Formable to Complex Shape
Ж Improve Fatigue Resistance
Ж Improve Creep resistance

4. TYPES OF FIBRE
Ж Natural fibers
Ж Advanced fibers

5. ADVANCED COMPOSITES FIBERS
Ж Carbon fiber
Ж Glass fiber
Ж Aramid
Ж ceramics

6. GLASS FIBERS
Ж Most versatile industrial materials known today.
Ж Produced from raw materials, which are available in
unlimited supply
Ж They exhibit useful bulk properties such as
 Hardness
 Resistance to chemical attack
 Stability and
 Inertness, as well as desirable
fiber properties such as
 strength, flexibility, and stiffness

7. GLASS FIBER TYPES
Ж Glass fibers fall into two categories, low-cost general-purpose
fibers and premium special-purpose fibers. Over 90% of all
glass fibers are general-purpose products.
Ж These fibers are known by the designation E-glass and are
subject to ASTM specifications
Ж The remaining glass fibers are premium special-purpose
products. Many, like E-glass, have letter designations
implying special properties
Ж Some have tradenames, but not all are subject to ASTM
specifications. Specifically:

8. GLASS FIBER MANUFACTURING

12. ARAMID FIBERS
Ж ARAMID FIBERS having the highest strength-to-weight ratio of
any commercially available reinforcement fiber at the time of
their first commercial introduction in the early 1970s.
Ж Characteristics
 light weight, high strength, and high toughness
Ж Used in tires, ropes, cables, asbestos replacement, and protective
apparel
Ж The disadvantage of aramid fibers is that they are difficult to cut
and machine.
Ж Aramid fibers are produced by extruding an acidic solution (a
proprietary polycondensation product of terephthaloyol chloride
and p-phenylenediamine) through a spinneret. The filaments are
drawn through several orifices.
Ж During the drawing operation, aramid molecules beome highly
oriented in the longitudinal direction.

14. CARBON FIBER

15. CARBON FIBER MANUFACTURING
Ж Major raw materials PAN and pitch
Ж 90% of the carbon fibers are made from polyacrylonitrile
(PAN).
Ж 10% of carbon fibers are made from pitch
Ж PAN is pre-manufactured synthetic fiber.
Ж Pitch is coal-tar petroleum product that is melted, twisted,
and stretched into fibers.

16. CARBON FIBER MANUFACTURING
Ж Typical sequence of operations used to form carbon fibers
from polyacrylonitrile (PAN):
 Thermoset treatment
 Carbonizing
 Graphitizing
 Surface Treating
 Epoxy Sizing

18. CARBON FIBER MANUFACTURING
Ж THERMOSET TREATMENT
 Fibers are stretched and heated to no more than 400 C.
 Cross-links carbon chains so that the fibers will not melt in
subsequent treatments.
Ж CARBONIZING
 fibers are heated to about 800 C in an oxygen free environment.
 removes non-carbon impurities.
Ж GRAPHITIZING
 heats them to temperatures ranging from 1100 C to 3000 C.
 stretches the fibers between 50 to 100% elongation. The stretching
ensures a preferred crystalline orientation

19. SURFACE TREATING
Ж After carbonizing, the fibers have a surface that does not
bond well with the epoxies and other materials used in
composite materials.
Ж To give the fibers better bonding properties, their surface is
slightly oxidized.
Ж provides
 better chemical bonding properties
 better mechanical bonding properties.
Ж The surface treatment process must be carefully controlled to
avoid forming tiny surface defects, such as pits, which could
cause fiber failure.

21. EPOXY SIZING
Ж Fibers are coated to protect them from damage during
winding or weaving. This process is called sizing.
Ж Typical coating materials include epoxy, polyester, nylon, and
others.
Ж The coated fibers are wound onto cylinders called spools.
Ж The spools are loaded into a spinning machine and the fibers
are twisted into yarns of various sizes.

23. CERAMIC FIBERS
Ж CERAMIC FIBERS are commercially available in two general
classes for the reinforcement of ceramic-matrix composites.
 oxide fibers, based on the alumina-silica (Al2O3-SiO2) system
 non-oxide fibers, silicon carbide (SiC).
Ж Fibers are typically produced with small diameter (<20 μm)
Ж A key characteristic of ceramic fibers is their
ultrafine microstructure, sometimes in the
nanometer range. Fine grains are required
for good tensile strength >2000 MPa

24. CERAMIC FIBERS PRODUCTION
Ж For oxide fibers, sol-gel processing is used.
 sol- gel process uses chemical solutions or colloidal suspensions,
which are shaped into fibers, then gelled (usually by drying) and heat
treated to convert the gelled precursor to ceramic.
Ж In the case of fibers based on SiC and silicon nitride,
 fibers are twisted from organometallic “pre-ceramic” polymer
precursors, followed by cross- linking (curing) and heat treatment
steps to convert the fibers to ceramic materials.

25. CERAMICS FIBER MANUFACTURING