Local heat clamp bending of carbon fiber-reinforced thermoplastic sheet

Abstract

Local heat clamp bending equipment for carbon fiber-reinforced thermoplastic (CFRTP) sheets has been developed. The equipment holds a CFRTP sheet with thin metal foils to heat the bending region to the resign melting temperature and then bends the sheet keeping the hold by the foils under continuous pressure application during cooling. Using this equipment, it has been revealed that even a unidirectional continuous carbon fiber sheet can be locally bent by the in-plane wavy deformation of the fiber in the inner plies, while keeping the same profile length of the outside ply. In contrast, in the bending of unidirectional carbon fiber sheets with cutting at constant length, a combination of the wavy deformation of the inside ply and expansion of the outside ply has been observed. The developed bending equipment will be useful for the bending of CFRTP sheets similar to how a press brake is used for sheet metal forming. The development of the local heat clamp bending equipment will expand a field of bending for mass production using CFRTP sheets.