An Investigation of the Physical and Mechanical Properties of Carbon Fibers Fabricated from Commercial and Special Polyacrylonitrile Fibers

Carbon fibers are special materials with unique properties (i.e., high specific strength and specific modulus) used as reinforcement in different composites in various applications, e.g., aerospace and defense industries. These fibers are mainly manufactured from special polyacrylonitrile (PAN) fibers. Their fabrication method is composed of oxidative stabilization at low temperature in an air atmosphere following by carbonization at high temperature in an inert atmosphere. However, the high price of these fibers is related to raw material (special PAN fibers) and processing costs. In this study, the properties of carbon fibers fabricated from low cost commercial PAN fibers are compared to carbon fibers produced by special PAN fibers. The results reveals that, carbon fibers could be fabricated by commercial fibers successfully, but their tensile strength, elastic modulus, and densities are less than the carbon fibers fabricated by special PAN fibers. Higher diameter, linear density, and lower tensile strength of commercial PAN fibers are the main parameters which decrease the properties of carbon fibers fabricated from them.