Carbon fiber or carbon fibre (alternately called graphite fiber, graphite fibre or carbon graphite) is a material consisting of extremely thin fibers about 0.0002–0.0004 inches (0.005–0.010 mm) in diameter and composed mostly of carbon atoms. The carbon atoms are bonded together in microscopic crystals that are more or less aligned parallel to the long axis of the fiber. The crystal alignment makes the fiber incredibly strong for its size. Several thousand carbon fibers are twisted together to form a yarn, which may be used by itself or woven into a fabric.[http://www.answers.com/topic/carbon-fiber?cat=technology carbon fiber: Definition and Much More from Answers.com ] Carbon fiber can be combined with a plastic resin and wound or molded to form composite materials such as carbon fiber reinforced plastic (also referenced as carbon fiber) to provide a high strength-to-weight ratio material. The density of carbon fiber is also considerably lower than the density of steel, making it ideal for applications requiring low weight. The properties of carbon fiber such as high tensile strength, low weight, and low thermal expansion make it very popular in aerospace, military, and motorsports, along with other competition sports.

History of Carbon Fiber

In 1957, Dr. Roger Bacon created the first high-performance carbon fibers at the Union Carbide Parma Technical Center, located outside of Cleveland, Ohio.The first fibers were manufactured by heating strands of rayon until they carbonized. This process proved to be inefficient, as the resulting fibers contained only about 20% carbon and had low strength and stiffness properties. In the early 1960s, a process was developed using polyacrylonitrile (PAN) as a raw material. This had produced a carbon fiber that contained about 55% carbon and had much better properties. The polyacrylonitrile (PAN) conversion process quickly became the primary method for producing carbon fibers.

On January 14, 1969 Carr Reinforcements (Stockport, England) wove the first ever carbon fiber fabric in the world.

During the 1970s, experimental work to find alternative raw materials led to the introduction of carbon fibers made from a petroleum pitch derived from oil processing. These fibers contained about 85% carbon and had excellent flexural strength.

Structure and properties

Carbon fibers are the closest to asbestos in a number of properties. Each carbon filament thread is a bundle of many thousand carbon filaments. A single such filament is a thin tube with a diameter of 5–8 micrometers and consists almost exclusively of carbon.