2009 Volume 58 Issue 7 Pages 642-648
High-speed compression molding process of carbon fiber reinforced thermoplastics (CFRTP) by means of electromagnetic induction heating system (IH system) using non-woven stitched multi-axial cloth (NSMC) were proposed in this study. This IH system allows heating of the mold surface instantaneously. There is no need to preheat the mold and the material before placing it in the mold. This system can also reduce production cycle times and the cost of manufacturing composite parts. Specimens were molded by a traditional hot press processing and IH system. While the hot press processing required 50 minutes to raise the temperature of the mold from 50°C to 250°C, IH system required only 70 seconds. Mold cooling of the IH system finished in only about 150 seconds. Comparing with the traditional hot press processing, this IH system can reduce production cycle time drastically. The CF/polyamide 6 specimens molded by IH system had higher bending strength and better impregnation than these molded by the hot press processing. While the void content of specimens molded by the traditional hot press processing were more than 10%, specimens molded by IH system had only about 5% void content. In case of IH system, not only mold but also carbon fiber itself is heated by electromagnetic field. Since this heated carbon fiber accelerates the resin impregnation into the carbon fiber bundle, the void content of the specimens molded by IH system is smaller than that by hot press.
