We fabricate CNT yarns from the CNT web. A CNT spun yarn is produced by twisting the CNT web with a spindle that moves backward with respect to the CNT forest and pulling it out. The number of twists and the twist angle are controlled by adjusting the spindle rotation speed and pulling speed. Typical twisting parameters are a rotation speed of 32,000 min-1 and a drawing speed of 120 mm/s. In this case, when spinning a CNT web with a width of 5 mm, the yarn diameter is about 20 μm and the twist angle is about 25°. The surface of CNT twisted yarn has a morphology similar to that of general twisted yarn.
Fabrication and mechanical properties of carbon nanotube yarns spun from ultra-long multi-walled carbon nanotube arrays
Adrian Ghemes, Yoshitaka Minami, Junichi Muramatsu, Morihiro Okada, Hidenori Mimura, Yoku Inoue
Carbon 50, 4579-4587 (2012).