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1. FIBER

2. TYPES
• Glass Fiber
• Carbon Fiber
• Graphite Fiber
• Aramid Fiber
• Boron Fiber
• Ceramic Fiber

3. Glass Fiber
• Common for Polymeric Matrix
• Advantages
• Low Cost
• High tensile strength
• High chemical resistance
• Excellent insulating property
• Disadvantages
• Low Modulus
• High specific gravity (relatively)
• Sensitive to abrasion( due to handling)
• Low fatigue resistance and high hardness leads to wear

4. TYPES OF GLASS FIBER
• E-Glass – E stands for electrical
• S-Glass – S stands for high silica content
» High thermal expansion coefficient
» High fatigue strength
• C-Glass – C stands for Corrosion
» Used in Chemical applications
» Storage tanks
• R-Glass – R stands for Rigid
» Structural applications
• D-Glass – D stands for Dielectric
» Low dielectric constants
• A-Glass – A Stands for appearance
» To improve surface appearance
» For ornamental works
• E-CR Glass – E-CR stands for Electrical and corrosion
resistance
• AR Glass – AR stands for Alkali resistance

5. PROPERTIES OF GLASS FIBER
Property E – Glass S – Glass
Specific Gravity 2.54 2.49
Young’s Modulus
(GPa)
72.4 85.5
Tensile Strength
(MPa)
3447 4585
Thermal Expansion
Coefficient
5.04 5.58

6. COMPOSITION OF GLASS FIBER
Material % by Weight
E – Glass S – Glass
Sio2 54 64
Al2O3 15 25
Ca2O3 17 0.01
MgO 4.5 10
B2O3 8 0.01
Others 1.5 0.8

7. Glass fiber Manufacturing
• Raw Material –
Sand, Alumina &
Lime Stone
Processing
Temperature:
1400 Degree C
for 45 Minutes
Pulled Through
Platinum Nozzles

8. CARBON FIBER
• Advantages
– High tensile strength to weight ratio
– High tensile modulus to weight ratio (due to graphitic
form of carbon)
– Low cost
– Low specific gravity
– Low thermal coefficient of expansion (Dimensionally
stable)
• Disadvantages
– Low impact resistance
– High electrical conductivity

9. • Carbon Fiber – 93 to 95 % of Carbon
• Graphite Fiber - > 99 % of Carbon
• Precursor Material
» Rayon
» PolyAcryloNitrile (PAN)
» Pitch

11. Spinnaret

12. Carbon fiber Manufacturing

14. PROPERTIES OF GRAPHITE
FIBER
Property Pitch PAN
Specific Gravity 1.99 1.78
Youngs Modulus
(GPa)
379.2 241.3
Tensile Strength
(MPa)
1723 3447
Thermal Expansion
Coefficient
-0.54 -1.26

15. ARAMID FIBERS
• Principle Constituents are
» C, H2, O2 & Nitrogen
• Advantages
» Low Density
» High Tensile Strength
» Low Cost
» High Impact Resistance
• Disadvantages
» Low Compressive properties
» Degrades under Sunlight
• Two Types
» Kevlar 29
» Kevlar 49

16. • Specific Stiffness of Kevlar 49 is high
when compared with Kevlar 29
• Kevlar 29 – Used in Bullet Proof vests,
Ropes and Cables
• Kevlar 49 – Aircraft Industry

17. PROPERTIES OF ARAMID FIBER
Property Kevlar 29 Kevlar 49
Specific Gravity 1.44 1.48
Youngs Modulus
(GPa)
62.05 131
Tensile Strength
(MPa)
3620 3620
Thermal Expansion
Coefficient
-2 -2

18. Characteristics of KEVLAR 49 Fiber
• Though tensile stress strain curve is linear fiber fracture is preceded
by fragmentation, splintering and even localized drawing.
• In bending Kevlar 49 fiber exhibit yielding on compression side. This
non-catastrophic failure leads to damage tolerance against impact or
dynamic loading.
• Use temperature recommended is 160 c
• Chemical resistance is good.
• Sensitive to ultra violet (add fillers to reduce)
• Prolong direct exposure to sunlight causes to dis- coloration and
loss in tensile strength ( problem is less in laminates)
• Hygroscopic and can absorb 6% moisture, however has less effect
• Low thermal conductivity and high damping coefficient

19. BORON FIBER
• High tensile Modulus
• Resistance to buckling
• High cost therefore restricted application.
Manufacturing
• By chemical vapor deposition of Boron on heated
substrate [Tungsten or carbon filament]
• Tungsten wire(0.0127 in dia) is pulled through a reaction
chamber[ 2Bcl3+3H2=2B+6Hcl] in which boron is
deposited on its surface at 1100-1300c
• Fiber diameter is controlled by pulling speed or
deposition temperature.

20. CERAMIC FIBER
• Silicon carbide and aluminum oxide fibers
are examples of ceramic fibers
• Best suited for Metal and Ceramic matrix
• High temperature application
• Monofilaments that are produced by Sic
on a 25 μm dia carbon filament substrate
( coated with pyrolitic graphite for
smoothening the surface

22. CLASSIFICATION OF
POLYMERIC RESINS
• Thermoplastics
» Weak bond – Vander Wall’s type
» Formable at high temperature
» Can be reprocessed
» Short cure cycle
» Excellent solvent resistance
» Polyethylene, polystyrene, polyether-ether-ketone
(PEEK), polyphenylene sulfide (PPS)
• Thermosets

23. POLYMERIC MATRIX
• Epoxy
• Polyester
• Phenolic
• Acrylic
• Urethane
• Polyamide

24. • Polyester
» Low cost
» Translucent in nature
» Operating temperature should be < 70 degree
» Brittleness
» High shrinkage rate
• Phenolic
» Low cost
» High mechanical strength
» High void content
• Epoxy
» High mechanical strength
» Good adhesive nature
» Low viscosity
» Low volatility
» Low shrinkage rate
» High cost

25. PROPERTY COMPARISON OF
RESINS

26. PROPERTIES OF EPOXY RESIN
Property Epoxy
Resin
Specific Gravity 1.28
Youngs Modulus
(GPa)
3.792
Tensile Strength
(MPa)
82.74

27. Incorporation of fiber into matrix
• Finished Structure
• Ready to mold sheets
Ready to mold fiber reinforced polymer
sheets are available in two forms
• Prepregs
• Sheet Molding Compounds

28. PREPREG
• Prepregs – Thin sheets of fibers impregnated
with predetermined amounts of uniformly
distributed polymeric matrix
• Width of prepregs sheets vary between 25 mm
to 457mm
• Sheets wider than 47 mm are Broad goods
• Thickness range from 0.13 – 0.25 mm
• Resin content is between 30 – 45 % by weight
• Normal Shelf life 6 – 8 days at 23 deg c
• When stored at – 18 deg C it can prolong upto 6
months

29. Prepreg Manufacturing

30. Sheet Molding Compound
(SMC)
– Chopped glass fiber added to polyester resin
mixture

31. Types of SMC
• SMC – R SMC – CR XMC

32. Material Forms
• Textile forms
–Braiding or weaving
• Tubular braided form
– can be flattened and cut for non-tubular
products

33. Fabric effects on material
properties