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The graphite fibers consists of >99% carbon. They are very similar to the carbon fibers with only the difference being that carbon fibers consist of 91-94% carbon [11]. This difference arises is due to the different processing temperature for both the fibers. The poly-acrylo-nitrile (PAN)-based carbon fiber is produced at 1320 °C, while graphite fibers are graphitized at 1950 to 3000 °C. The physico-chemical properties of graphite are unaffected at elevated temperatures; yet, it can readily react with the metals during its processing, e.g. aluminium matrices produces the carbides at their interface [8]. The stiffness of the fiber increases with the graphite content. However, with the increase in stiffness, the strength decreases. The graphitic fibers are expensive and in PAN based fibers, other raw materials are equally expensive.