8/7/2019 Presentation- Javed (1)
1/43
GRAPHITE REINFORCED
COMPOSITES
TO
DR.AHMAD TINDYALA
BY: Muhammad Javed
2009-MS-PE-10
8/7/2019 Presentation- Javed (1)
2/43
Contents
Introduction to CFRPC
Types of Carbon Fiber
DIFFERENT GRAPHITE REINFORCED COMPOSITES
ADVANTAGES OF CFRPC
DISADVANTAGES OF CFRPC
MANUFACTURING PROCESSES
Applications
8/7/2019 Presentation- Javed (1)
3/43
Carbon Fiber Reinforced Polymer
(CFRP) is a Polymer Matrix Composite
material reinforced by carbonfibers.
The reinforcing dispersed phase may be inform of either continuous or discontinuous
carbon fibers of diameter about 0.0004
(10 mkm) commonly woven into a cloth.
Carbon fibers possess the highest specificmechanical properties: modulus of
elasticity and strength.
8/7/2019 Presentation- Javed (1)
4/43
Carbon Fiber Reinforcement
Most expensive reinforcement.
In aerospace applications the combinationof excellent performance characteristicscoupled with light weight make the cost of
secondary importance.
Today, high cost carbon fiber alone and inhybrid form is widely used in highperformance applications where
performance to cost advantages exist.4
8/7/2019 Presentation- Javed (1)
5/43
Properties of CRPC
Very high modulus of elasticity exceeding
that of steel
High tensile strength, which may reach1000 ksi (7 GPa);
Low density: 114 lb/ft (1800 kg/m);
High chemical inertness.
8/7/2019 Presentation- Javed (1)
6/43
Disadvantage
Catastrophic mode of failure (carbon fibers
are brittle).
Cost
Heterogeneous Anisotropic
8/7/2019 Presentation- Javed (1)
7/43
Types of Carbon Fibers
UHM (ultra high modulus). Modulus of elasticity
> 65400 ksi (450GPa).
HM (high modulus). Modulus of elasticity is in
the range 51000-65400 ksi (350-450GPa). IM (intermediate modulus). Modulus of elasticity
is in the range 29000-51000 ksi (200-350GPa).
HT (high tensile, low modulus). Tensile strength> 436 ksi (3 GPa), modulus of elasticity < 14500
ksi (100 GPa).
SHT (super high tensile). Tensile strength > 650
ksi (4.5GPa).
8/7/2019 Presentation- Javed (1)
8/43
8
Carbon (IM)
A variety of fiber grades are produced:
Carbon (HM)
Carbon (UHM)
Intermediate Modulus
High Modulus
Ultra-high Modulus
Typically, the stiffer the
fibre, the lower the
strength and strain to
failure.
Grades of Carbon FiberReinforcement
8/7/2019 Presentation- Javed (1)
9/43
Manufacturing of Carbon Fiber
Reinforcement
9
There are a number of precursors for the
development of carbon fibers including
Cellulose fiber
Polyacrylonitrile fiber
Lignin
pitch
High strength, highmodulus
Largely produced by
these precursors
Lower strengthfiber
8/7/2019 Presentation- Javed (1)
10/43
Manufacturing of Carbon Fiber
Reinforcement Carbon fibers are produced by controlled
oxidation and carbonization of the precursorfiber at temperatures up to 2600C resulting inhigh strength fiber
Increasing the temperature to 3000C results inthe conversion of high strength fiber to highmodulus graphite fiber
Conversion of polyacrylonitrile fiber to carbon
fiber is more efficient than that using cellulosefiber, owing to high carbon content of precursor.
Sizing with a resin also improves handling andprevents damage during processing
10
8/7/2019 Presentation- Javed (1)
11/43
Manufacturing Method
. PAN-based carbon fibers (the most
popular type of carbon fibers).
CFare produced by conversion ofpolyacrylonitrile (PAN) precursor
PAN manufacturing
process:
8/7/2019 Presentation- Javed (1)
12/43
Pitch-based Carbon Fibers
Carbon fibers of this type aremanufactured from pitch:
Filaments are spun from coal tar or
petroleum asphalt (pitch). The fibers are cured at 600F (315C).
Carbonization in nitrogen atmosphere at a
temperature about 2200 F (1200C).
8/7/2019 Presentation- Javed (1)
13/43
Pitch-based Carbon Fibers
8/7/2019 Presentation- Javed (1)
14/43
14
8/7/2019 Presentation- Javed (1)
15/43
Matrix Materials forManufacturing CFRP
The most popular matrix materials for
manufacturing Carbon Fiber ReinforcedPolymers (CFRP) are thermosets such as
epoxy, polyester and thermoplastics suchas nylon (polyamide).
Carbon Fiber Reinforced Polymers
(CFRP) materials usually have laminatestructure, providing reinforcing in twoperpendicular directions.
8/7/2019 Presentation- Javed (1)
16/43
Graphite in Epoxy Resin
Graphite addition reduces the friction coefficient andwear loss drops significantly when graphite is presentin small amounts in the resin.
composites containing 3wt% or more of graphiteyielded extremely small amounts of wear.
Material thickness and fiber orientations can beoptimized for each application
8/7/2019 Presentation- Javed (1)
17/43
Graphite in Epoxy Resin
Surface resistance and resistivity
Surface resistance and resistivity decreased together bydecreasing of specimen thickness. It is obvious result ofincreasing content of graphite filler in sequential, deeper
placed layers. Addition of 3 to 6%vol. of graphite toepoxy resin caused limited, almost linear, decrease ofsurface resistance and resistivity in depth direction ofspecimens. But addition of 9 to 12%vol of graphite inpolymeric composite caused rapid, non-linear with layer
depth, decrease of surface resistance and resistivity. It isin accordance with possibility of forming spatial networkby conductive filler particles
8/7/2019 Presentation- Javed (1)
18/43
Graphite in Epoxy Resin
Surface resistance and resistivity
Results scatter for composite with 12%vol of graphite
was probably caused by non-homogenous fillerdistribution in composite volume. High viscosity of this
composite made mixing very difficult.
8/7/2019 Presentation- Javed (1)
19/43
Graphite Fiber-reinforced
Polyimide Composites Polyimide/graphite fiber-reinforced composites are widely
applied to the manufacture of various aerospace structures.The main advantage of polyimide composites is their ability
to retain In plane mechanical properties at temperatures up to
250 to 350C which is the result of a very high glass transitiontemperature of a polyimide matrix.
These composites are successfully applied in the Application:
Aerospace honeycomb design, providing significant weight
reduction and long-term functioning at increased temperatures.Typically, such honeycomb panels include graphite fiber-reinforced polyimide sheets adhesively bonded to the fiberglass core
8/7/2019 Presentation- Javed (1)
20/43
Disadvantage:
low interlaminar fracture toughness and tendency to
delaminating. This arises from the three dimensional stressfield and the presence of transverse stresses
M t l M t i C it
8/7/2019 Presentation- Javed (1)
21/43
Metal-Matrix Composite
Materials and Applications
The metal matrix composites offer higher modulus ofelasticity, ductility, and resistance to elevatedtemperature than polymer matrix composites. But, theyare heavier and more difficult to process
8/7/2019 Presentation- Javed (1)
22/43
8/7/2019 Presentation- Javed (1)
23/43
CFRP are Characterized bythe Following Properties
Light weight;
High strength-to-weight ratio;
Very High modulus elasticity-to-weight ratio;
High Fatigue strength;
Good corrosion resistance;
Very low coefficient of thermal expansion
Low impact resistance
High electric conductivity;
High cost.
G l Ch t i ti f C it
8/7/2019 Presentation- Javed (1)
24/43
General Characteristics of Composite
MaterialsComparison with CRPC
Fibers
Matrix materials
8/7/2019 Presentation- Javed (1)
25/43
25
Tensile Stress-Strain Curves for different
Fiber/Epoxy Systems, Aluminum and Steel
8/7/2019 Presentation- Javed (1)
26/43
26
8/7/2019 Presentation- Javed (1)
27/43
27
8/7/2019 Presentation- Javed (1)
28/43
28
8/7/2019 Presentation- Javed (1)
29/43
Utilization of Carbon Fiber
Reinforcement
Carbon fibers are supplied in a number ofdifferent forms, from continuous filament toes tochopped fiber mat
Highest strength and modulus are obtained byusing unidirectional reinforcement.
Twist free tows of continuous filament carbon
contain 5000-10000 individual filaments whichcan be woven into woven roving and hybrid
fabrics with glass fiber and poly-aramid fiber
29
8/7/2019 Presentation- Javed (1)
30/43
Graphite Reinforced composites
The graphite fiber sheets may be impregnatedwith, and bonded together by, any suitable resin
during preform manufacture. Impregnation may be accomplished by any
suitable technique, such as solution dipping,spraying, hot-melt coating, etc.
8/7/2019 Presentation- Javed (1)
31/43
CFRP are used forManufacturing
Automotive marine and aerospace parts
Sport goods (golf clubs, skis, tennisracquets, fishing rods)
Bicycle frames.
Electronic and electrical industries
8/7/2019 Presentation- Javed (1)
32/43
Composite Materials withinthe Aerospace Industry
Graphite/Carbon
Fiberglass
Kevlar
Thermoset Plastic
8/7/2019 Presentation- Javed (1)
33/43
8/7/2019 Presentation- Javed (1)
34/43
8/7/2019 Presentation- Javed (1)
35/43
Courtesy : Gary Eisenberg; Antelope Valley Community College; Lancaster , CA
Composites-Boeing 777
Composites B2 Stealth Bomber
8/7/2019 Presentation- Javed (1)
36/43
Courtesy : Gary Eisenberg; Antelope Valley Community College; Lancaster , CA
Composites B2 Stealth Bomber
Weight Savings for Automotive Light
8/7/2019 Presentation- Javed (1)
37/43
Lightweight Material Material Replaced
Mass Reduction (%)
High Strength Steel Mild Steel 10
Aluminum (AI) Steel, Cast Iron 40 - 60
Magnesium Steel or Cast Iron 60 - 75
Magnesium Aluminum 25 - 35
Glass FRP Composites Steel 25 - 35
Graphite FRP Composites Steel 50 - 60
Al matrix Composites Steel or Cast Iron 50 - 65
Titanium Alloy Steel 40 - 55
Stainless Steel Carbon Steel 20 - 45
Weight Savings for Automotive Lightweighting Materials
8/7/2019 Presentation- Javed (1)
38/43
Manufacturing of Graphitic Foam
A suitable graphite foam can be made by dissolving atelevated temperatures (about 300C.) and pressures
as much nitrogen as possible into a high qualitymesophase pitch. When the pressure is relieved, the
nitrogen expands, forming a pitch foam. The pitchfoam is then oxygen stabilized at about 200-250C.to crosslink the pitch to strengthen the foam. Finally,
the pitch foam is heat treated at high temperatures(about 2,000-2,500F.) in an inert atmosphere to forma graphite foam.
Graphitic Foams
8/7/2019 Presentation- Javed (1)
39/43
Graphitic Foams
Properties of the foam
an isotropic bulk thermal conductivity as high as 150W/mK
specific conductivity up to 6 times greater than that of copper
high thermal conductivity, low weight, low density, 0.27 to 0.57g/cm3
low coefficient of thermal expansion,
high specific strength and low cost
Graphitic open celled network throughout the foam (unlikecarbon fiber reinforced composites)
A dramatically smaller automobile radiator has been developedwith the foam.
Applications of Foam
8/7/2019 Presentation- Javed (1)
40/43
Applications of FoamThis material is an enabling technology for thermal
management problems ranging from Heat sinks
Radiators Satellite panels to aircraft heat exchangers. High-density electronics
Hybrid diesel-electric vehicles Communication satellites
In addition, the open porosity will lead to novel designs
that incorporate porous media heat exchangers and phasechange materials. For example, by utilizing the foam as aheat exchanger, heat transfer coefficients over two orders
of magnitude greater than current metallic designs havebeen measured.
8/7/2019 Presentation- Javed (1)
41/43
Foam heat sink in Pentium 133 microprocessor
Computer chip heat sinks made from graphitic foam
8/7/2019 Presentation- Javed (1)
42/43
8/7/2019 Presentation- Javed (1)
43/43
THE END