ozzle system. SAF solution (14% w/w) prepared by dissolving the fiber in DMF. The nanofiber yarn had an average diameter of 111.4µm. The average nanofiber diameter was 397nm. The nanofiber yarns were drawn continuously in boiling water with drawing ratios of 1,2,3 and 4. The drawn yarns as well as untreated yarn were tested for tensile properties. The results showed that the tenacity and modulusThis project was aimed to investigate the Effects of Hot Pre-stretching o the properties of PAN-Based Carbon Nanofiber yarn. The nanofiber yarn was produced by two-n of yarn increases as a result of drawing. X-ray diffraction patterns the nanofiber yarns with draw ratios of 2 and 4 as well as the untreated yarn were analyzed. It was found that Crystallinity Index increases as the draw ratio increases. The crystallite size increased to draw ratio 2 but decreased for draw ratio 4. However the crystallite size of yarn with draw ratio 4 is higher than the untreated nonofiber yarn. The untreated yarn and the drawn nanofiber yarn with draw ratio 4 were heat stabilized first at 220, 240 and 260?C (15 minutes each temperature). The carbonization was carried out in the presence of N 2 at temperatures 260-800?C. Scanning Electron Micrographs of untreated, drawn and carbon nanofiber yarns were prepared and then surface morphology was investigated. It was shown that drawing increases the orientation of nanofibers relative to the yarn axis.
