textile composites and its application

 Composites are produced by reinforcing a resin matrix thermoplastic/thermoset with fibres like glass fibre, aramid, carbon fibre and/or natural fibres... Reinforcement  The reinforce

BY ALANKAR G MHATRE FINAL YEAR B.TECH

INTRODUCTION TO COMPOSITES

 You might be know we all are surrounded by composites in day today life.

 Everybody comes across composites in his daily life.You might be playing

tennis or badminton with a "graphite racket", You might have a "carbon bike" ,your bike breaks are made of composite, several parts of your car body are also made of composites.

 Def :-A composite is a material made up of two or more different materials

that are combined in a way that allows the materials to stay distinct and

identifiable

 The purpose of composites is to allow the new material to have strengths

from both materials.

• Composites can be easily found in nature Wood is an example of a

composite Another natural composite is rock and sand, materials used in concrete

 Properties of composites like stiffness, thermal expansion etc can be

varied continuously over a broad range of values using appropriate fiber , resin and fabrication mechanism

 The technical textile material in the composites is the fiber glass,

aramid and carbon fiber.

• Fibre glass dominates the composites industry as a preferred

reinforcement fibre, with a share of around 85%-90% Other

reinforcement fibers like carbon fibre and aramid fibre are sparingly used in India.

WHAT ARE COMPOSITES?

 Composites are created by combining two or more materials to

produce a new material that retains important properties from the original elements

 Reinforcing fibers give composites the attributes of high strength

and stiffness.

 In textile composites fibers are surrounded by a choice of polymers

that act as a support system.

 Composites are produced by reinforcing a resin matrix

(thermoplastic/thermoset) with fibres like glass fibre, aramid, carbon fibre and/or natural fibres

 A common example of a composite is concrete It

consists of a binder as a cement and a reinforcement as

a gravel

COMPOSITION OF COMPOSITES

 The individual materials that make up composites are called

constituents Most composites have two constituents, a matrix and reinforcement

 Composite materials are usually classified by the type of

reinforcement they use This reinforcement is embedded into a matrix that hold it together

 The reinforcement is used to strengthen the composite Composite

properties are best in the direction of the fibers Perpendicular, or

transverse, to the fibers, the matrix properties dominate because load

must be transferred by the matrix every fiber diameter

Reinforcement

 The reinforcement is usually much stronger and stiffer than the matrix, and

that gives the composite its good properties

 The matrix hold the reinforcements in an orderly pattern, the matrix also

helps to transfer load among the reinforcements

 Reinforcements basically come in three forms: particulate, discontinuous

fiber, and continuous fiber.

PARTICLE AS A REINFORCEMENT:-A particle has roughly

equal dimensions in all directions, though it doesn't have to be spherical Gravel, micro balloons, and resin powder are examples of particulate

reinforcements

become fibers when one dimension becomes long compared to others

DISCONTINUES FIBERS AS A REINFORCEMENT:

-:Discontinuous reinforcements (chopped fibers, milled fibers, or whiskers) vary in length from a few millimeters to a few centimeters Most fibers are only a few microns in diameter, so it doesn't take much length to make the transition from particle to fiber

 Matrix materials are usually some type of plastic, and

these composites are often called reinforced plastics.

 There are other types of matrices, such as metal or

ceramic, but plastics are the most

 The two most common plastic matrices are epoxy

resins and polyester resins

TYPES OF COMPOSITES

 Metal matrix composites (MMC)

 Ceramic matrix composites (CMC)

 Polymer matrix composites (PMC)

Metal matrix composites (MMC)

• Metal matrix composites (MMCs) are a subgroup of composite materials.



Composition:- MMC are made by dispersing a reinforcing material into a metal matrix The

reinforcement surface can be coated to prevent a chemical reaction with the matrix.

 For example, carbon fibers are commonly used in aluminum matrix

to synthesize composites showing low density and high strength However, carbon reacts with aluminum to generate a brittle and water-soluble

compound Al4C3 on the surface of the fiber To prevent this reaction, the carbon fibers are coated with nickel or titanium boride.



Matrix:- In structural applications, the matrix is usually a lighter metal such as

aluminum, magnesium, or titanium, and provides a compliant support for the reinforcement

 In high temperature applications, cobalt and cobalt-nickel alloy matrices are common

Reinforcement to MMC

 The reinforcement can be either continuous, or discontinuous

Discontinuous MMC can be isotropic, and can be worked with

standard metalworking techniques, such as extrusion, forging or

rolling

 In addition, they may be machined using conventional techniques,

but commonly would need the use of polycrystalline diamond tooling (PCD).

 Continuous reinforcement uses monofilament wires or

fibers such as carbon fiber or silicon carbide.

 One of the first MMC used boron filament as

reinforcement Discontinuous reinforcement uses

"whiskers", short fibers, or particles

 The most common reinforcing materials in this category

are alumina and silicon carbide

Ceramic matrix composites

 Ceramic matrix composites (CMCs) are a subgroup of composite

materials as well as a subgroup of technical ceramics.

 They consist of ceramic fibers embedded in a ceramic matrix, thus forming a ceramic fiber reinforced ceramic (CFRC) material

 The matrix and fibers can consist of any ceramic material, whereby

carbon and carbon fibers can also be considered a ceramic

material.

 Generally, CMC names include a combination of type of fiber / type

of matrix For example, C/C stands for carbon-fiber-reinforced

carbon (carbon/carbon), or C/ SiC for carbon-fiber-reinforced

silicon carbide

Ceramic composites

REINFORCEMENT- SiC (Silicon carbide)

MATRIX-Cu Metal

Polymer Matrix composites

 Polymer matrix composites are the imp and third subgroup of

composites.

 It is also referred as fibre-reinforced plastics(FRP)

 In these fibre-reinforced plastics, the plastic is reinforced with

fibers to make a light and strong material The material in

which the fibres are embedded, is called the matrix, while the

fibres are called the reinforcement.

 The matrix can basically be any type of plastic: epoxy, polyester,

vinyl ester, polypropylene (PP).

Matrix examples for PMC

• polyether sulphide (PES)

• polyphenylene sulphide (PPS)

• polyether imide (PEI)

• polyether ether ketone (PEEK)

The fibres are typically glass, carbon (graphite) or aramid (trade name Kevlar) The fibre reinforcement can take any form: a mat

of short chopped fibres, a woven fabric, a unidirectional

arrangement of fibres, a braid, a knit.

Glass fabrics Plain weave glass

fabric

Manufacturing and forming methods of

MMC

 MMC manufacturing can be broken into three types: solid,

liquid, and vapor.

Solid state

methods:- 1)-Powder blending and consolidation (powder metallurgy):-

Powdered metal and discontinuous reinforcement are mixed and then bonded through a process of compaction, degassing, and thermo-mechanical treatment (possibly via hot isostatic pressing (HIP) or extrusion)

 2)-Foil diffusion bonding:-Layers of metal foil are

sandwiched with long fibers, and then pressed through to form

a matrix

Liquid state methods FOR MMC

 1)-Electroplating / Electroforming:- A solution

containing metal ions loaded with reinforcing particles is co-deposited forming a composite material

 2)-Stir casting:- Discontinuous reinforcement is stirred

into molten metal, which is allowed to solidify

 3)-Squeeze casting:- Molten metal is injected into a

form with fibers preplaced inside it

 4)-Spray deposition:- Molten metal is sprayed onto a

continuous fiber substrate

 5)-Reactive processing:- A chemical reaction occurs,

with one of the reactants forming the matrix and the

other the reinforcement

Vapor deposition

 Physical vapor deposition: The fiber is

passed through a thick cloud of vaporized metal, coating it

Manufacturing procedures for Ceramic

matrix composites

1)-Matrix deposition from a gas

phase:- Chemical vapor deposition (CVD) is well suited for this purpose

In the presence of a fiber perform, CVD takes place in between the fibers and their individual filaments and therefore is called chemical vapor

infiltration (CVI)

 One example is the manufacture of C/C composites: a C-fiber perform is

exposed to a mixture of argon and a hydrocarbon gas (methane, propane, etc.) at a pressure of around or below 100 kPa and a temperature above

1000 °C

2)-Matrix forming via pyrolysis of C- and Si-containing

polymers- Hydrocarbon polymers shrink during paralysis, and upon out gassing form carbon with an amorphous, glass-like structure, which by additional heat treatment can be changed to a more graphite-like structure

 Other special polymers, where some carbon atoms are replaced by

silicon atoms, the so-called polycarbosilanes, yield amorphous silicon

carbide of more or less stoichiometric composition

• Subsequent curing and pyrolysis yield a highly porous matrix, which is

undesirable for most applications Further cycles of polymer infiltration and pyrolysis are performed until the final and desired quality is achieved

Usually five to eight cycles are necessary

 The process is called liquid polymer infiltration (LPI), or polymer

infiltration and pyrolysis (PIP) Here also a porosity of about 15% is

common due to the shrinking of the polymer The porosity is reduced after every cycle

APPLICATION OF COMPOSITES

• Applications of Métal matrix composites (MMC)–

1 Carbide drills are often made from a tough cobalt matrix with hard tungsten

carbide particles inside

2 Some tank armors may be made from metal matrix composites, probably steel

reinforced with boron nitride Boron nitride is a good reinforcement for steel because it is very stiff and it does not dissolve in molten steel

3 Honda , Toyotas automobiles has used aluminum metal matrix composite

cylinder liners in some of their engines,

4 Specialized Bicycles has used aluminum MMC compounds for its top of the

range bicycle frames for several years Griffen Bicycles also makes boron

carbide-aluminum MMC bike frames, and Univega briefly did so as well

5 Some automotive disc brakes use MMC Modern high-performance sport

cars, such as those built by Porsche, use rotors made of carbon fiber within a silicon carbide matrix because of its high specific heat and

thermal conductivity

A typical composites material construction

for helicopter blade

Metal matrix composites

Applications Of ceramic matrix composites

• Heat shield systems for space vehicles, which are needed during the re-entry

phase, where high temperatures, thermal shock conditions and heavy vibration loads take place

• Components for high-temperature gas turbines such as combustion chambers,

and turbine blades

• Components for burners, flame holders, and hot gas ducts, where the use of oxide

CMCs has found its way

• Disks breaks and brake system components, which experience extreme thermal

shock

Applications of FRP or PMC

• Fibre-reinforced plastics are best suited for any design program that

demands weight savings, precision engineering, finite tolerances, and the simplification of parts in both production and operation A moulded polymer artefact is cheaper, faster, and easier to manufacture than cast aluminum or steel artefact, and maintains similar and sometimes better tolerances and material strengths

• Overall reduction in production and operational costs, economy of parts

results in lower production costs and the weight savings create fuel savings that lower the operational costs of flying the aero plane

Design considerations

PMC IN AIRCRAFT PARTS

LIGHT WEIGHT

APPLICATION PMC IN RAILWAYS

 For passenger coach components.

 Components of coaches are generally made of glass

fibre reinforced with polyesters/epoxies, phenolic

resins.

Minardi Formula 1

All Formula One race cars have a carbon fibre monocoque structure that protects the driver for all crashes.

BMC frame with carbon/epoxy pre-preg

One of the most well-known composite applications in

sports is the so-called "carbon bike" The frame consists

of carbon fibre-reinforced epoxy which makes the frame very stiff and lightweight.

BMW M6 with carbon fibre roof

In automotive applications, composites are all around us Just as

in sports applications, weight reduction is pushing the designers to use more and more composites The examples are numerous.

Composites Today's Material of

Choice

 It gives lower manufacturing costs, composite material continues to

penetrate new markets and applications For industries that

traditionally use assemblies made from more traditional options such

as steel, wood or concrete, composites offer a dynamic alternative – especially for those products that are difficult to assemble or costly to manufacture as a result of increasing steel pieces Glass fibre as

reinforcement dominates the sector of composites material with a

share of 85-90%.

• Composites are created by combining two or more materials to produce a new material that retains important properties from the original elements

 Reinforcing fibers give composites the attributes of high strength and

stiffness which in the industrial arena translates to high performance

These fibers are surrounded by a choice of polymers that act as a support system, transferring load between fibers and protecting the fibers from the

operating environment.The burgeoning infrastructure sectors project

involving highways, bridges, airports, buildings, and construction, power generation and transmission, telecommunications are expected

to provide an impetus to the composites industry in India.

 Composites can also deliver reduced manufacturing/assembly

costs Since liquid resin can flow into any shape, products with complex shapes can be made at a lower cost when compared

to conventional methods using traditional materials

• Typically, complex shapes of metals or wood require labor intensive

assembly of multiple pieces to create the product Composites can

provide ultimately the lowest cost alternative

 The lower cost of unitized composite parts is particularly

attractive for customers that purchase products assembled

from many metallic pieces or have difficult-to-form shapes.

Properties of composite

products

 Tensile strength of composites is four to six times greater than that of

conventional materials like steel, aluminium etc.

 Improved torsion stiffness and impact properties

 Higher fatigue endurance limit (up to 60% of the ultimate tensile strength)

 30-45% lighter than aluminium structures designed for the same functional

requirements

 Lower embedded energy

 Composites are less noisy while in operation and provide lower vibration

transmission

 Composites are more versatile and can be tailored to meet performance

needs and complex design requirements