Study On Continuous Carbon Fiber Treatment And Its Reinforcement On The Properties Of Nylon Thermoplastic Composites

In recent years,carbon fiber composite materials have become the focus in the research and development of lightweight technology.Continuous carbon fiber(CCF)reinforced thermoplastic composites have high specific strength,specific stiffness,fatigue resistance,and other properties,as well as good toughness,processability,and recyclability,and have become research scholars in the fields of automobile manufacturing,rail transit,and aerospace.The focus of the industry’s competition is to develop.Different from traditional carbon fiber composite materials,the application of thermoplastic matrix brings about new problems such as reinforcement mechanism and function,and it is urgent to carry out systematic research and innovation in principle and process method.Therefore,this paper aims to prepare highperformance continuous carbon fiber reinforced nylon composites.From the perspective of improving the interface properties of carbon fiber and thermoplastic matrix,the carbon fiber desizing,surface treatment,and other pretreatment processes are studied,and the hot-pressing process parameters are studied.Preparation and properties of continuous carbon fiber reinforced PA6 composites under the influence.Accordingly,this paper has carried out research work in the following three aspects:(1)Using XPS and other testing and characterization methods,the effect of hightemperature heating and desizing process parameters of T300B-3K continuous carbon fiber from Toray Company on the properties of reinforced PA6 composites was studied.The research results show that the nylon composites prepared from carbon fibers treated at 450℃ for 1 h with a desizing process have excellent comprehensive mechanical properties.Compared with the sample without desizing,the tensile strength of the carbon fiber reinforced nylon 6 composite after desizing increases from 301 MPa to 396 MPa,an increase of 31.6%,and its flexural strength and interlaminar shear strength increase by 70.7%,respectively.and 44.4%.The necessity of applying continuous carbon fibers to the desizing process of thermoplastic composites is verified.(2)The continuous carbon fibers were surface-treated by liquid-phase oxidation,coupling agent,surface coating,etc.,and the mechanical properties,thermal properties,microstructure,and damp-heat aging properties of the prepared carbon fiber-reinforced nylon 6 composites were systematically studied.The research results show that the content of N element on the surface of carbon fiber after surface treatment increases by 159.8%,the content of O element increases by 65.3%,and the presence of 9.1%Si element is detected,which verifies the effectiveness of the surface treatment.The improvement of the interface bonding between the surface-treated carbon fiber and the PA6 matrix further increases the tensile strength,flexural strength,and interlaminar shear strength of the composite by 21.2%,17.4%,and 17.1%,respectively.(3)Continuous carbon fiber reinforced nylon 6 composites were prepared by film lamination hot pressing process,and the influence of main heat pressing parameters on the structure and properties of continuous carbon fiber reinforced nylon 6 composites was studied.The research shows that the continuous carbon fiber reinforced nylon 6 composites prepared under the conditions of heat pressing temperature of 270℃,hot pressing pressure of 5 MPa,and heat pressing time of 10 min have a tensile strength of 396 MPa,a flexural strength of 541 MPa,and an ILSS of 41.2MPa.