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Back to Introduction page |
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| Production process |
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| According to "Carbon Fibers" by Raghavendra R. Hegde, AtulDahiya, M. G. Kamath (Monika Kannadaguli & HaomingRong)- updated April 2004 carbon fiber can be made from a variety of precursor materials. Based on what material was used the carbon fiber is classified as one of the following: |
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| -- PAN-based carbon fibers |
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| -- Pitch-based carbon fibers |
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| -- Mesophase pitch-based carbon fibers |
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| -- Isotropic pitch-based carbon fibers |
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| -- Rayon-based carbon fibers |
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| -- Gas-phase-grown carbon fibers |
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| The fibers are then heated to varying temperatures to give the end product the desired properties. Below is a section from the document "Carbon Fibers" by Raghavendra R. Hegde, AtulDahiya, M. G. Kamath (Monika Kannadaguli & HaomingRong)- updated April 2004 detailing the manufacturing process of carbon fibers from polyacrylonitrile (PAN), one of the most common ways of producing carbon fiber. Although carbon fibers can be made from many different materials some of the most common are PAN (as shown below), "cellulosic" fibers such as cotton and rayon, and coal and petroleum tar pitch. |
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| "Carbon fibers from POLYACRYLONITRILE (PAN): |
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| There are three successive stages in the conversion of PAN precursor into high-performance carbon fibers. Oxidative stabilization: The polyacrylonitrile precursor is first stretched and simultaneously oxidized in a temperature range of 200-300 o C. This treatment converts thermoplastic PAN to a non-plastic cyclic or ladder compound. Carbonization: After oxidation, the fibers are carbonized at about 1000 o C without tension in an inert atmosphere (normally nitrogen) for a few hours. During this process the non-carbon elements are removed as volatiles to give carbon fibers with a yield of about 50% of the mass of the original PAN. Graphitization: Depending on the type of fiber required, the fibers are treated at temperatures between 1500-3000 o C, which improves the ordering, and orientation of the crystallites in the direction of the fiber axis." |
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| This see a schematic representation of carbon fiber preparation from PAN fibers (from the source below) |
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| To view the entire excellent document on carbon fiber and, for more information on precursor materials for carbon fibers click the link below |
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| Information and image from |
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| "Carbon Fibers" by Raghavendra R. Hegde, AtulDahiya, M. G. Kamath (Monika Kannadaguli & HaomingRong)- updated April 2004 |
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| http://www.engr.utk.edu/mse/pages/Textiles/CARBON%20FIBERS.htm |
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