Study On The Processing Technology And Mechanical Properties Of Long Carbon Fiber Reinforced Thermoplastic Composites

Carbon fiber reinforced thermoplastic composites have attracted more and more attention due to their excellent mechanical properties and recoverable.In this paper,the unidirectional prepreg tapes was prepared by powder fluidization electrostatic adsorption,and long carbon fiber prepreg was prepared by chopped carbon fiber tape reinforced thermoplastic.Finally,long carbon fiber reinforced thermoplastic composite was prepared by hot pressing,and its Mechanical properties were studied.First in this paper,through the way of machinery broadening device to broadening of the carbon fiber tapes,The carbon fiber tapes passes around two stationary rollers and then around a roller that can reciprocate,by moving back and forth of the rolls,and the tension of the fibre to produce a change to broadening the fiber.It was experimentally obtained,This machinery broadening device can broadening of the carbon fiber tapes from 6mm to 30 mm,and the width to 5 times than before.According to the damage analysis of the carbon fiber,that strength damage was only 5.47% before and after the broadening.After broadening of the carbon fiber,the powder impregnation is carried out on the expanded fiber.The fiber first passes through a powder coating chamber,and the powder gun sprays a mist of negatively charged matrix powder into the coating chamber.The fiber tapes to the matrix powder then passes through a high-temperature melting chamber,and then passes through a hot pressing roller,finally through a rewinding machine.In this paper,the influence of the hot-pressing process and fiber mass fraction on the tensile properties of carbon fiber reinforcement unidirectional prepreg tapes were investigated.When the fiber quality fraction is 65wt%,hot-pressing temperature is 250?,hot pressing pressure is 1.5MPa,hot pressing time is 10 min,it has the best performance,and the maximum tensile strength is 1168.8 MPa.Long carbon fiber reinforced thermoplastic prepreg was prepared by chopped the unidirectional prepreg tapes.The length and width of the prepreg after cutting were both 10 mm.The long carbon fiber reinforced PA6 composite material was prepared by hot pressing which use the chopped carbon fiber tape-reinforced thermoplastics.The influence of the hot-pressing process and fiber mass fraction on the mechanical properties was studied.It was found that when the fiber mass fraction was 55wt%,the hot-pressing temperature was 260?,the hot-pressing pressure was 4.6MPa,and the hot-pressing time was 30 min,the tensile performance of the composite material was the best,and the tensile strength of the composite material was 403.07 MPa.Finally,the strength of the composite material was predicted by means of stiffness degradation and continuous damage mechanics.By comparing with the experimental results,it was found that the predicted results were in good agreement with the experimental results.