| Popis: |
Carbon fibers are commercially produced from both PAN and petroleum pitch-based processes. PAN-based fibers are usually circular or dogbone-shaped in cross section due to the nature of the precipitation processes used in their production. Pitch-based fibers are melt spun and thus (like other melt-spun fibers) can be extruded into a wide variety of non-circular shapes. In this investigation trilobal and octalobal carbon fibers were melt spun using a precursor produced from petroleum pitch. These non-circular fibers were oxidized and carbonized at conditions typically used in processing circular carbon fibers. Then the fiber modulus, strength and structure was compared to that of circular fibers produced as a control. Surprisingly, the non-circular carbon fibers, which possess a unique structure, have both a higher strength and modulus than the circular carbon fibers. |
