Processing And Properties Research Of Carbon Fiber Composite Front Floor Of Automobile

With the high strength, high modulus, flexible molding process, as well as the excellent lightweight effect, carbon fiber reinforced resin composites have been widely used in the field of aerospace, wind vane, sports equipment, as well as automobile parts. In particular, it has a significant reduction effect on the weight of the vehicle body. However, due to the anisotropy of carbon fiber composite materials are different from the isotropy of metal materials, so the structural design and molding method are more complex than metal materials, therefore, it has not been widely used, especially in the civil context, so it is very important to research the carbon fiber composite automobile parts in detail.In this issue, the composite automobile front floor was the research object. Resin matrix and carbon fiber as well as other raw materials were studied and selected in detail, and the molding process were explored. Using vacuum assisted resin injection (VARI) molding process, the suitable curing process for the composite automobile front floor and beams is80℃/2h+110℃/2h+140℃/2h with the use of the biphenyl A resin system. Accordingly, the tensile strength, bending strength, impact strength and glass transition temperature of the casting matrix are73.52MPa,128.12Mpa,17.17KJ/m2and138℃, respectively. A comparison of the mechanical properties of the T300plain weave carbon fiber cloth between the domestic and the imported was conducted in this study, and the layup of the carbon fiber was [0°/90°4s.The study of the mechanical properties of the composite of the carbon fiber with the layup of [0°/90°4s,[0°/+45°/90°/-45°2s [+45°/-45°4s reinforced the biphenyl A resin system through vacuum assisted resin injection (VARI) molding process showed that the mechanical properties were the best with the layup of [0°/90°4s, the tensile strength, tensile modulus, flexural strength, flexural modulus, and the interlaminar tensile of the composite are896.46MPa,49.82GPa,815.93MPa,45.33GPa,52.58Mpa for the domestic plain weave carbon fiber cloth, and956.71MPa,57.31GPa,904.76MPa,52.54MPa,53.71Mpa for the T300plain weave carbon fiber cloth, respectively. This paper also used advanced composite autoclave molding process to prepare the automobile beams.we study on the T300 unidirectional prepreg and the T300unidirectional prepreg of the autoclave molding processmechanical properties of composites with different layups, which showed that the best overlay modewas0°90°4s,which can obtain the optimal mechanical properties of composites,and the tensilestrength, tensile modulus, flexural strength, flexural modulus, and the interlaminar tensile of thecomposite are1236.58MPa,69.89GPa,1189.60MPa,65.43GPa,84.26Mpa. With the obtainedperformance parameters of the automobile front floor board and beams of the T300plain weavecarbon fiber reinforced biphenyl A type resin composite, we further studied on the fabrication of thecomposite front floor board and beams with the VARI molding process. Thereafter, the carbon fibercomposite front floor board and beams were successfully fabricated. Using metallographicmicroscope, the fiber volume content of composite automobile front floor board is57.4%. Moreover,the fiber volume is different on the different positions of front floor board, which is61%at the mainboard plate and53%in the corner of the front floor board.Furthermore, through the research on bonding test, the MAXLOKT6hybrid structural gluewas used as adhesive in the composite automobile front floor. The weight of the compositeautomobile front floor and the spar which were fabricated by the VARI and autoclave moldingprocess respectively, were13.6kg and14.8kg. Compared to the metal front floor of automobile,weight was reduced by49.63%and45.19%respectively. What is more, the stiffness of theautomobile front floor and the spar which were fabricated by the VARI molding process, werecomparative with that of the metal one. And that of the stiffness of the front floor is twice of themetal one. Lastly, the result of the assembling test was conducted. Results showed that the modelfrequency of the white automobile body was comparative with that of the metal ones.