Textile CompositesShahrukh Shahbaz

• The term "composite" can be used in several different ways, and the definition can range from general to very specific. • A broad definition of a composite is: "Two or

more dissimilar materials which when combined are stronger than the individual materials."

What is a Composite?

What is a Composite?

• While the broad definition of composites is accurate, it is too general. • Composite materials (or composites for short)

are engineered materials made from two or more constituent materials with significantly different mechanical properties and which remain separate and distinct within the finished structure.

CLASSIFICATION OF COMPOSITE MATERIALS:

Composite materials

Fibre reinforced composites

Carbon carbon

composites

Metal matrix

composites Ceramic

compositesOrganic

compositesEngineered wood

Plastic impregnated or

laminated paper

Brief History of Composites

The use of natural composite materials has been a part of man's technology since the first ancient builder used straw to reinforce mud bricks.

• Israelites' use of chopped straw in their brick

HISTORY OF COMPOSITES

The Egyptian sarcophagi fashioned from glued and laminated wood veneer and also their use of cloth tape soaked in resin for mummy embalming

The Etruscan "Sarcophagus of the Spouses", at the

National Etruscan Museum

HISTORY OF COMPOSITES

• the Mongol warriors' high-performance, recurved archery bows of bullock tendon, horn, bamboo strips, silk and pine resin, which are 80% as strong as our modern fiberglass bows

A modern reconstruction, in fibreglass and wood, of a historical composite bow

COMPOSITION OF A COMPOSITE MATERIAL:

• Composites are made up of individual materials referred to as constituent materials• There are two categories of constituent materials• Matrix • Reinforcement

MATRIX (RESIN SYSTEMS)

• Matrix holds the reinforcements in an orderly pattern• The matrix also helps to transfer load • 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 by far the most common

MATRIX (RESIN SYSTEMS) • The choice of a resin system for use in any

component depends on a number of its characteristics., with the following probably being the most important for most composite structures:

• 1.      Adhesive Properties• 2.      Mechanical Properties• 3.      Micro-Cracking resistance• 4.      Fatigue Resistance• 5.      Degradation from Water Ingress

TYPES OF MATRIX (RESIN SYSTEMS)

• Most commonly used resin systems are: • Polyester resins• Vinyl ester resins• Epoxy resins

Some Properties of Resin Systems:

REINFORCEMENTS

• The role of the reinforcement in a composite material is fundamentally one of increasing the mechanical properties • All of the different fibres used in composites have different

properties and so affect the properties of the composite in different ways

REINFORCEMENTS

• Individual fibres or fibre bundles can only be used on their own in a few processes such as filament winding. For most other applications, the fibres need to be arranged into some form of sheet, known as a fabric, to make handling possible.

RE-INFORCEMENT TYPES

REINFORCEMENTS

• These fabrics can be made through different textile techniques such as braiding, weaving, knitting and sometimes even Non wovens can be used as reinforcements.• Therefore the utilization of all these textile techniques gave

rise to the name TEXTILE COMPOSITES.

PROPERTIES OF REINFORCED FIBERS

• The four main factors that govern the fibre’s contribution are:1.      The basic mechanical properties of the fibre itself.2.      The surface interaction of fibre and resin (the ‘interface’).3.      The amount of fibre in the composite (‘Fibre Volume Fraction’).4.      The orientation of the fibres in the composite.

Material Type Tensile Strength(MPa)

Tensile Modulus(GPa)

Typical Density(g/cc)

Specific Modulus

Carbon HS 3500 160 - 270 1.8 90 - 150

Carbon IM 5300 270 - 325 1.8 150 - 180

Carbon HM 3500 325 - 440 1.8 180 - 240

Carbon UHM 2000 440+ 2.0 200+Aramid LM 3600 60 1.45 40Aramid HM 3100 120 1.45 80Aramid UHM 3400 180 1.47 120Glass - E glass 2400 69 2.5 27Glass - S2 glass 3450 86 2.5 34Glass - quartz 3700 69 2.2 31

Aluminium Alloy (7020) 400 1069 2.7 26

Titanium 950 110 4.5 24Mild Steel (55 Grade)

450 205 7.8 26

Stainless Steel (A5-80) 800 196 7.8 25

HS Steel (17/4 H900) 1241 197 7.8 25

TYPICAL PROPERTIES OF SOME REINFORCEMENTS:

WAYS TO MANUFACTURE A COMPOSITE MATERIAL

• Engineered composite materials must be formed to shape• The matrix material can be introduced to the reinforcement

before or after the reinforcement material is placed into the mould cavity or onto the mould surface• The matrix material experiences a moulding event, after

which the part shape is essentially set

WAYS TO MANUFACTURE A COMPOSITE MATERIAL

• Depending upon the nature of the matrix material, this melding event can occur in various ways such as chemical polymerization or solidification from the melted state.• In general, the reinforcing and matrix materials are

combined, compacted and processed to undergo a melding event• After the melding event, the part shape is essentially set

MOULDING TECHNIQUES

• There are different type of moulding processes which can be utilized to form a composite material. These can be• Vacuum bag moulding• Pressure bag moulding• Autoclave moulding• Resin transfer moulding (RTM)

VACUUM BAG MOULDING

• The Re-inforcement is impregnated into the polymer and laid onto the mould with supportive layers.• The edges of the vacuum bag are sealed against the edges of the

mould surface to enclose the part against an air-tight mould.• Vacuum is drawn on the vacuum bag and atmospheric pressure

compresses the material for shaping. • After sealing the part inside the vacuum bag, a vacuum is drawn on

the part (and held) during cure.

VACUUM BAG MOULDING

AIR PUMP FOR VACCUM BAGGING

PRESSURE BAG MOULDING

• It is similar to vacuum bag molding.• A solid female mold is used along with a flexible male mold. • The reinforcement is placed inside the female mold with just enough resin to allow

the fabric to stick in place (wet lay up). A measured amount of resin is then liberally brushed indiscriminately into the mold and the mold is then clamped to a machine that contains the male flexible mold.

• The flexible male membrane is then inflated with heated compressed air or steam. • Excess resin is forced out along with trapped air.• Commonly used for production of composite helmets.• Cycle time is 20 to 45 minutes.• Finished shells require no further curing if the molds are heated.

PRESSURE BAG MOULDING

AUTO CLAVE MOULDING

• It is possible to create pressure and heat at the same time in the Autoclave.• Layers of pre-impregnated Re-inforcement are piled with varying orientation, to

form the desired thickness above the forming tool. • The prepreg is pressed down to the forming tool by pressure. • Following heating hardens the matrix and the laminate gets the desired shape. • The process is very versatile and gives a very uniform quality, as pressure and

heat can be regulated very precisely. Any geometry can be produced. • On the other hand, it is very costly and time requiring.

AUTO CLAVE MOULDING

RESIN TRANSFER MOULDING

• RTM involves a rigid two-sided mold set that forms both surfaces of the panel.• The mold is typically constructed from aluminum or steel. • The two sides fit together to produce a mold cavity. • The distinguishing feature of resin transfer molding is that the reinforcement materials are

placed into this cavity and the mold set is closed prior to the introduction of matrix material. • Resin transfer molding includes numerous varieties which differ in the mechanics of how the

resin is introduced to the reinforcement in the mold cavity. • Used for making high-tech aerospace components.• This process can be performed at either ambient or elevated temperature.

RESIN TRANSFER MOULDING

TEXTILE COMPOSITES...THE WAY FORWARD

• APPLICATIONS IN THE AEROSPACE INDUSTRY: • Composite materials comprise around 50% of the Boeing 787

airframe. Carbon-fibre reinforced plastic and glass-fibre reinforced plastic are used extensively in wings, fuselage sections (such as the undercarriage and rear end of fuselage), tail surfaces, and doors.

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APPLICATIONS IN THE CONSTRUCTION INDUSTRY

• Textile composites have been used in construction since the 1960s, and• Though they do not hold a prominent place compared with

that of traditional• Construction materials, their use is on the increase

DESIGN FLEXIBILITY

APPLICATIONS IN THE AUTOMOTIVE INDUSTRY

• Composites have long been used in autos and trucks, primarily under the hood and in interiors. • High-performance have used carbon fiber for many years,

and now new high-speed manufacturing technology is allowing carbon fiber to move into production vehicles.

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APPLICATIONS IN THE MARINE INDUSTRY

• The marine market is the most deeply penetrated of all end markets served by the composites industry. • Yachts, sailboats and other craft make substantial use of gel

coat, core material, glass fiber and, in some applications, carbon fiber.

APPLICATIONS IN THE SPORTS INDUSTRY

• Conventional composite materials generally consist of a reinforcing textile structure and a surrounding matrix with other mechanical properties

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APPLICATIONS IN THE DEFENCE INDUSTRY

• In 2007 an all-composite military High Mobility Multi-purpose Wheeled Vehicle (HMMWV or Hummvee) was introduced by TPI Composites Inc and Armor Holdings Inc, the first all-composite military vehicle. • By using composites the vehicle is lighter, allowing higher

payloads

APPLICATIONS IN THE WIND TURBINES

• The blades of the Wind Turbines are also composed of composite materials involving Carbon and Glass fiber Composites due to below advantages• High Strength• Low Weight• Toughness• Corrosion Resistance

CONCLUSION

• Composites have versatility in the usage for below factors• Durability• Thermal Resistance• Water Resistance• Higher Strength to Weight Ratio• Corrosion Resistance• Environmental Durability

• A lot of research is being carried on improvement and materialization of more applications of composites.

THANK YOU