Pneumatic Technology for Spreading a Carbon Fiber Tow and Experimental Investigation

Pneumatic spreading technology is introduced in this paper and a pneumatic spreading system was designed to spread carbon fiber tows to improve the invasion of resin to middle and large carbon fiber tows and strengthen the mechanical properties of Carbon Fiber Reinforced Plastics (CFRP). In the system a high speed vacuum pump was used to pump air and the air streams flew through the fibers and pulled them to the lateral sides in parallel. Experiments were carried out to research the effects of air velocity, tension and feeding velocity of carbon fibers on spreading process and the spreading results under various conditions were analyzed. The experimental results show that thin carbon fiber tows in good uniformity can be obtained through reasonable control of air velocity at 13-16 m.s(-1), tension at 6-20 g and fibers feeding velocity at 5-7 m.min(-1).