Chapter-5

Overview on Specialty Fibers

Bademaw Abate

Cont……Specialty fibers are engineered for specific

uses that require :exceptional strength heat resistance and/or chemical resistance.

high performance fibers are driven by special technical functions that require specific physical properties unique to these fibers

They are generally niche products, but some are produced in large quantities.

Cont…Commodity fibers: are typically used in a highly competitive price environment which translates into large scale high volume programs.

FIBER PROPERTIES AND THEIR APPLICATIONS

Aramid Fiber:

Cont…..

Kevlar

• Due to their highly oriented rigid molecular structure, para-aramid fibers have high tenacity, high tensile modulus and high heat resistance.

Nomex• meta-aramids are best known for their

combination of heat resistance and strength

Applications-“bullet-proof” body armor,Helmets Application-suits of fire fighters,

insulation

HDPE HDPE (high-density polyethylene) can be

extruded using special technology to produce

very high molecular orientation.

The resulting fiber combines high strength,

chemical resistance and good wear properties

with light weight, making it highly desirable

for applications ranging from cut-proof

protective gear to marine ropes.

Since it is lighter than water, ropes made of

HDPE float.

Its primary drawback is its low softening

and melting temperature

PTFE (PTFE, polytetrafluoroethylene) offers extremely high

chemical resistance, coupled with good thermal stability.

It also has an extremely low coefficient of friction, which

can be either an advantage or disadvantage, depending on

the use.

Applications-bearing Replacement, Hot gas filtrations and

Test tubes

Glass All glass fibers derived from compositions containing Silica, which are

available in virtually unlimited supply.

They exhibit useful bulk properties such as Hardness, Transparency,

Resistance To Chemical Attack, Stability, and Inertness, as well as

Desirable Fiber Properties such as Strength, Flexibility, and

Stiffness.

Glass fibers are used in a number of applications which can be divided

into four basic categories: (A) Insulations, (B) Filtration Media, (C)

Reinforcements, And (D) Optical Fibers.

Types of Glass Fiber A GLASS – Soda lime silicate glasses used where the Strength, Durability, And

Good Electrical Resistivity.

C GLASS-- Chemical Stability In Corrosive Acid Environments.

D GLASS – Borosilicate glasses with a Low Dielectric Constant For Electrical

Applications.

E GLASS – Alumina-calcium-borosilicate glasses with a maximum alkali content

of 2 wt.% used as general purpose fibers where strength and High Electrical

Resistivity are required.

R GLASS – Calcium aluminosilicate glasses used for reinforcement where added

strength and acid corrosion resistance are required.

Carbon Carbon fiber has very high tensile strength.

It has low thermal expansion.

It is a light weight material having low density.

It is a good conductor of electricity.

high wear resistance.

It has long working life.

It’s density is less than density of steel.

Cont…

It is insensitive to change in temperature.

It’s properties is much better than any of the other

metals.

It’s compressive strength is greater than all the

reinforcing material.

APPLICATIONS It is mostly used in the aerospace and aircraft industries. It is used in making sports equipment such as light weight badminton

rackets, golf stick etc. Automotive body is also made up of the carbon fiber Constructing up of wind mill blades.

THANK YOU

THE END