Study On The Preparation Of Continuous Carbon Fiber Reinforced PEEK Prepreg Tapes Through Melt Impregnation Method

Compared with thermosetting composites(FRSP),thermoplastic composites(FRTP)have the characteristics of recycling,good toughness,good durability,excellent fatigue resistance,etc.,which have great application potential in the fields of military weapons,aviation equipment,automotive parts,sports equipment,civil engineering and so on.Continuous carbon fiber reinforced polyether ether ketone(CF-PEEK)composite has excellent temperature resistance,flame retardancy,high mechanical properties,high wear resistance and other properties,and is an indispensable key material in modern industry(such as aviation).Due to the high melting viscosity of PEEK,it is difficult to prepare continuous carbon fiber PEEK by melt impregnation method,which restricts its industrial application.In this paper,the melting impregnation process of carbon fiber PEEK was analyzed theoretically.The Taguchi method was used to optimize the melting impregnation parameters to prepare continuous carbon fiber reinforced PEEK prepregnation belt,and the mechanical properties of the prepregnation belt were studied systematically.Firstly,the effects of impregnation temperature,traction speed and roller radius on impregnation pressure were quantitatively studied based on Reynolds equation.It was found that the higher the impregnation temperature,the lower the impregnation pressure.The faster the traction speed,the larger the roller radius,the greater the impregnation pressure.Based on geometric model and numerical simulation method,the effects of impregnation pressure,fiber bundle width,roller radius,impregnation temperature,traction speed and roller spacing on the impregnation degree of the prepared CF-PEEK prepregnation tape were studied.It was found that the impregnation degree increased with the increase of fiber bundle width,impregnation pressure,roller diameter and impregnation mold temperature.Increases with the decrease of traction speed and impregnating roller spacing.The main factors affecting the impregnation degree are traction speed,fiber bundle broadening,impregnation pressure,impregnation roller diameter and impregnation mold temperature,while the impregnation roller spacing has less effect.The effect of process parameters on the performance of CF-PEEK prepreg strip was analyzed by Taguchi method.The results show that the extruder feeding speed,impregnation temperature and traction speed are the main factors affecting the performance of the prepreg strip.Taguchi analysis and impregnation process theory reveal the same rule of influence of process parameters.The theoretical analysis is verified by experiments.The theory established in impregnation process can effectively guide the production process.Combined with Taguchi optimization and impregnation theory,the optimized parameters of continuous CFR-PEEK prepreg strip were proposed,and a continuous CFR-PEEK prepreg strip with the reduced tensile strength of 1900 MPa,the reduced tensile modulus of 220 GPa and the mass fraction of carbon fiber of about 50% along the fiber direction were prepared.