Manufacturing and Mechanical Characterization of Low-cost Isotropic Pitch-based Carbon Fiber

Download or read book Manufacturing and Mechanical Characterization of Low-cost Isotropic Pitch-based Carbon Fiber written by Viren Jayantibhai Patel and published by . This book was released on 2021 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this study was to manufacture and mechanically characterize low-cost carbon fiber derived from pitch-based precursor that meets or exceeds the general-purpose carbon fiber. For this study, isotropic coal-tar pitch precursor was used due to its ease in manufacturing carbon fiber and low-cost starting material. Various analyses such as elemental composition, softening point, TGA, FT-IR, NMR, single carbon fiber testing, and SEM were performed to fully characterize the precursor and carbon fiber. Using melt spinning method, the precursor was melt spun at 235 °C, a pressure of 1.5 MPa and a winding speed of 400 rpm to achieve continuous small diameter fibers known as spun/green fibers. The winding speed of the drum collector and the spinneret diameter controlled the overall diameter of the carbon fibers. The green fibers then underwent the thermal treatment processes of stabilization and carbonization. The green fibers were oxidized at 300 °C with a heating rate of 0.25 °C/min in air. Later, they were carbonized at 1100 °C with a heating rate of 1 °C/min in an inert environment. Experimentally it was determined that smaller diameter carbon fibers were easy to fully oxidize with a smaller heating rate. This also resulted in higher mechanical properties due to less defects in their structures. The isotropic pitch-based carbon fiber manufactured in this study have the maximum tensile strength and elastic modulus of 927 MPa and 86 GPa, respectively.