Mechanical Properties of Thermoplastic Composites Made of Commingled Carbon Fiber/Nylon Fiber

Commingled yarns consisting of thermoplastic nylon fibers and carbon fibers can be used to produce superior carbon fiber reinforced thermoplastics (CFRTP) by applying fiber spreading technology after commingling. In this study, we examined whether spread commingled carbon fiber/nylon fiber yarns could reduce the impregnation distance, as there are few reports on this. From this study, the following are revealed. The impregnation speed of the nylon resin on the carbon fiber was very fast, less than 1 min. As the molding time increased, the tensile strength and tensile fracture strain slightly decreased, and the nylon resin deteriorated. The effects of molding time on flexural strength, flexural modulus, and flexural fracture strain were negligible. From the cross-sectional observation conducted to confirm the impregnation state of the matrix resin, no voids were observed in the molded products, regardless of molding time or molding pressure, indicating that resin impregnation into the carbon fiber bundle of the spread commingled yarn fabric was completed at a molding pressure of 5 MPa and a molding time of 5 min.

Automated summary

The study found that spreading commingled carbon fiber/nylon fiber yarns can effectively reduce the impregnation distance, with rapid nylon resin impregnation on the carbon fibers. However, an increase in molding time resulted in a slight decrease in tensile strength and tensile fracture strain, as well as degradation of the nylon resin. The effects of molding time on flexural strength, flexural modulus, and flexural fracture strain were negligible.