碳纤维复合材料汽车前地板成型工艺及性能研究

发布时间：2018-02-04 19:07

本文关键词： 前地板汽车轻量化 VARI成型热压罐成型刚度　出处：《东华大学》2015年硕士论文　论文类型：学位论文

【摘要】：碳纤维增强树脂基复合材料以其高强度、高模量、成型工艺灵活、轻量化效果十分明显等优点,在航天航空、风机叶片、体育器材、汽车零部件中得到了广泛的应用,特别是在车身结构件中,轻量化效果尤为明显；但是由于碳纤维复合材料的各向异性不同于金属材料的各向同性,使其在结构设计和成型加工方法上比金属材料复杂,因此还未得到广泛的应用,尤其是在民用方面,因此对碳纤维复合材料汽车零部件详细系统的研究显得尤为重要。本课题以复合材料汽车前地板为研究对象,对树脂基体和碳纤维等原材料进行了详细的研究和筛选,并对成型工艺进行了探索,确定了适用于前地板主板和梁VARI成型工艺用双酚A型树脂体系的最佳固化工艺为80℃/2h+110℃/2h+140℃/2h,按照此固化工艺制备的树脂浇铸体的拉伸强度、弯曲强度、冲击强度和玻璃化转变温度分别为73.52MPa、128.12Mpa、17.17KJ/m2和138℃。对国产和进口T300级平纹碳纤维进行力学性能研究,确定了适用于前地板主板和梁VARI成型工艺用增强材料为进口T300级平纹碳纤维,且铺层方式为[0°/90°]4s。通过VARI工艺成型[0°/90°]4s、[0°+45°/90°/-45°]2s、[+45°/-45°]4s三种不同铺层方式增强双酚A型树脂体系复合材料的力学性能的研究表明,以[0°/90°]4s铺层方式得到的复合材料力学性能最优，其拉伸强度、拉伸模量、弯曲强度、弯曲模量、层间剪切强度分别为896.46MPa和956.71MPa、49.82GPa和57.31GPa、815.93MPa和904.76MPa、45.33GPa和52.54GPa、52.58MPa和53.71MPa；本课题还采用先进复合材料热压罐成型工艺制备了汽车横梁，对热压罐工艺成型T300级单向预浸料和不同铺层间复合材料的力学性能进行了研究，结果表明以0°90°4s为最优的铺层方式，得到的复合材料力学性能最优，其拉伸强度、拉伸模量、弯曲强度、弯曲模量、层间剪切强度分别为1236.58MPa、69.89GPa、1189.60MPa、65.43GPa、84.26MPa。在获得了前地板主板和梁用树脂体系和碳纤维基本性能参数后，对VARI工艺成型前地板主板和梁的工艺进行了研究，并且成功制备了前地板主板和梁；采用金相显微镜测试了前地板主板的纤维体积含量为57.4%，并且在不同位置，纤维体积含量不同；在主板平板处，纤维体积含量为61%，，在主板拐角处，纤维体积含量为53%。通过对胶接试验的基础性研究，确定了MAXLOKT6混合型结构胶作为前地板胶接用结构胶；对胶接完成后的前地板称重，发现梁用VARI工艺和用热压罐工艺成型组装的前地板重量分别为13.6kg和14.8kg，相比于原金属前地板，重量分别降低了49.63%和45.19%；对前地板进行刚度测试，结果表明前地板梁用VARI工艺成型的前地板的刚度与原金属前地板刚度相当，而前地板梁用热压罐工艺成型的前地板的刚度约是其两倍；最后对制备的前地板进行装车试验，并对装车后的白车身进行了模态测试，结果表明其与原金属车身的模态频率相当，满足汽车前地板的性能要求。
[Abstract]:Resin based composite material with high strength, high modulus carbon fiber reinforced lightweight, flexible forming process, the effect is very obvious advantages in aerospace, fan blades, sports equipment, auto parts has been widely used, especially in the vehicle body structure, lightweight effect is obvious; but due to anisotropy specific carbon fiber composite material is different from the metal material isotropic, the structure design and molding method than metal material is complex, it has not been widely used, especially in civilian areas, so it is very important to the carbon fiber composite material with auto parts of the system.
The composite automobile front floor as the research object, the matrix resin and carbon fiber and other raw materials has been screened and studied in detail, and the molding process are explored, determine the best curing process for the front floor board and beam forming process of VARI with bisphenol A type resin is 80 DEG /2h+110 /2h+140 OC /2h, in accordance with the tensile strength of the resin curing process prepared by casting the bending strength, impact strength and glass transition temperature were 73.52MPa, 128.12Mpa, 17.17KJ/m2 and 138 DEG. Research on the mechanical properties of domestic and imported T300 plain carbon fiber, is determined to apply the front floor board and beam VARI forming process of reinforced materials used for the import T300 plain carbon fiber layer, and the way for [0 ~ /90 ~]4s. by VARI process [0 ~ /90 ~]4s, [0 ~ +45 ~ /90 ~ /-45 ~]2s, [+45 ~ /-45 ~]4s three different layers Study on enhancement of mechanical properties of bisphenol A type resin composites showed that the optimal mechanical properties of the composites with [0 ~ /90 ~]4s layers obtained, the tensile strength, tensile modulus, flexural strength, flexural modulus and interlaminar shear strength were 896.46MPa and 956.71MPa, 49.82GPa and 57.31GPa, 815.93MPa and 904.76MPa, 45.33GPa and 52.54GPa, 52.58MPa and 53.71MPa; this project also uses tank forming advanced composite hot pressing technology for automobile beam preparation, mechanical properties of autoclave moulding grade T300 unidirectional prepreg and between different layers of composite materials were studied, the results show that the 0 degrees 90 degrees 4S for the form of lamination optimum. The optimal mechanical properties of the composites obtained, the tensile strength, tensile modulus, flexural strength, flexural modulus and interlaminar shear strength were 1236.58MPa, 69.89GPa, 1189.60MPa, 65.43GPa, 84.26MPa.
In the front floor board and beam with the basic performance parameters of resin and carbon fiber, on the floor board and beam VARI technology before forming process were studied, and successfully prepared the front floor board and beam; the front floor board of the fiber volume fraction of 57.4% was tested by optical microscope, and in different the position, the fiber volume fraction is different; in the motherboard plate, the fiber volume fraction is 61%, the motherboard in the corner, the fiber volume fraction is 53%.
The adhesive test of basic research, to determine the MAXLOKT6 hybrid structure adhesive bonding structure as the front floor glue; weighing to the front floor adhesive after the completion of the discovery process of VARI and beam assembled by autoclave moulding before the floor weight were 13.6kg and 14.8kg, as compared to the original metal the floor, the weight was reduced by 49.63% and 45.19%; the stiffness test of the front floor, the results show that the first floor beam with the front floor of VARI process and the stiffness of the original metal floor stiffness, the floor beam before using the autoclave moulding the floor stiffness is about two times; at last loading test on the front floor preparation, and the white body after loading the modal test, the results show that with the original metal body modal frequency, meet the performance requirements of automobile front floor.

【学位授予单位】：东华大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U466;TB332

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