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Carbon is a high-performance fiber material which is often used as reinforcement in advanced polymer-matrix composites. The reasons being that:

1 a) The carbon fibers hold maximum specific modulus and strength among all other reinforcing fiber materials.

2 b) They can retain their tensile modulus and strength at elevated temperatures.

3 c) The carbon fibers are not at all affected by moisture, acids, and bases at room temperature.

4 d) Due to their exciting physical and mechanical characteristics, the composite thus formed tends to have specific engineered properties.

5 e) Inexpensive and cost effective manufacturing processes for fiber and composite have been developed.

Carbon fibers are not purely crystalline, but they possess both graphitic and non-crystalline regions. These non-crystalline regions are composed of the 3-D ordered arrangement of hexagonal carbon networks which is also characteristic of graphite. The techniques to produce carbon fibers are relatively complex. Rayon, polyacrylonitrile (PAN), and pitch are used as organic precursor materials for producing carbon fibers [3]. The processing techniques are different for different precursors and also affect the resultant fiber characteristics. The carbon fibers can be classified on the basis of tensile modulus; which is further divided into four subclasses as standard, intermediate, high, and ultrahigh moduli. The diameters of both continuous and chopped fibers normally range between 4 and 10 μm. The carbon fibers are coated with a protective epoxy size which improves its adhesion with the polymer matrix. Carbon-reinforced polymer composites are utilized in sports and recreational equipment, pressure vessels, helicopters, aircraft (military and commercial) structural components and filament-wound rocket motor cases.