Fibre Reinforced Polymer.

Fibre Reinforced Polymer;

Fibre reinforced polymer are also called fibre reinforced plastic.
A composite is a combination of two or more materials which differ in form or composition on a macroscale.
Fibre reinforced polymer (FRP) is a composite that consist of high performance fibres embedded in a polymer matrix.
Fibres utilized in FRP are carbon, glass and aramid.
Polymers utilized in FRP are epoxy, vinyl ester, polyester and phenol formaldehyde resins.
Fibre reinforced composites can have different arrangement of fibres within the polymer.

(a) One dimensional arrangement;

Here the fibres are only aligned in X-direction.

(b) Two dimensional arrangement, random;

Here the fibres are randomly aligned in X-direction and Y-direction.

(c) Two dimensional arrangement, oriented;

Here the fibres are aligned in X-direction and Y-direction in a particular manner.

(d) Three dimensional arrangement, random;

Here the fibres are randomly aligned in X-direction, Y-direction and Z-direction.

Different arrangement of fibres within the polymer.

The function of polymer in the composite is to transfer stress between reinforcing fibres and to protect the fibres from mechanical and environmental damage.
Carbon and aramid fibres exhibit good chemical resistance. Glass fibres can be damaged in alkaline media.
Carbon and glass fibres are not affected by UV rays. Aramid fibres lose color and strength on exposure to UV rays.
FRPs are commonly used in the aerospace, automotive, marine, and construction industries.
FRPs are commonly found in ballistic armour.

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