Formability and flow front observation of carbon/polyamide 6 randomly oriented strand composites during compression molding

Abstract

Chopped carbon fiber tape-reinforced thermoplastics are randomly oriented strand materials that are easy to process and have good mechanical properties. Studying the formability and flow evolution during compression molding is essential; in particular, clarifying the relationship between the forming parameters and mold-filling characteristics of highly concentrated fiber suspensions. Here, we investigated the key parameters of strand size and effective pressure and demonstrated filling a complex mold cavity under practical processing conditions. In addition, a simplified method for observing the progression of the flow front using a video camera was proposed, where the dependence of the applied load on the mold-filling time could be observed. Filling complex-shaped mold cavity using chopped carbon fiber tape-reinforced thermoplastics is achievable using shorter strands and higher pressures. Also, the degradation of mechanical performance should be carefully considered when the material undergoes large deformation to form complex-shaped products.