碳纤维复合板材超声振动热冲压变形行为的研究

汽车轻量化对碳纤维增强树脂基复合材料制造的板材零件需求日益增加，现有的手工铺层、热压罐、树脂传递模塑成形等工艺方法耗时长、效率低、成本高，仅适用实验室及小批量试制。本项目提出了适用于碳纤维增强树脂基复合材料板材工业化批量生产的新工艺：将该板材在具有超声振动的加热模具作用下直接冲压成形。本项目建立了碳纤维复合材料板材超声振动热冲压力学模型，揭示了该新型板材热冲压成形的变形机理；获得了超声振动施加时振幅、频率和温度等因素对复合材料流动和接触面摩擦的影响规律；研究了碳纤维增强树脂基复合材料板材超声振动热冲压时的细观与宏观力学行为；建立了该复合材料的多场耦合热态冲压过程模拟有限元模型，揭示了该复合材料板材本身纤维剪切角对其冲压时起皱、破裂失效及工件机械性能的影响机制；开展复合材料板材的超声振动热弯曲和拉深实验研究，获得了工艺参数对其冲压质量的影响规律与合理的工艺参数。

The increasing demand for vehicle lightweighting requires carbon fiber reinforced resin matrix composites (CFRRMC) parts. However, the existing forming methods, such as hand lay-up, autoclave moulding and resin transfer molding, etc., could only be used for laboratory and small batch manufacture, due to the time-consuming, inefficient and costly processes. This project develops a new forming process which can be used for manufacture of CFRRMC shell parts in batch quantity. The parts can be formed directly by ultrasonic vibration-assisted stamping CFRRMC sheet under the heated die. This project will establish ultrasonic vibration-assisted thermal stamping mechanical model of CFRRMC sheet, and investigate the deformation mechanism of the new forming process. The effects of ultrasonic vibration amplitude, frequency and temperature on composite flow and contact friction are obtained. The meso and macro mechanical behavior of CFRRMC sheet in ultrasonic vibration-assisted thermal stamping process are researched. The multi-field coupling finite element model of CFRRMC sheet thermal stamping is established, and the effects of composite material shear angle on wrinkling, fracture and the mechanical properties of formed composite parts during thermal stamping are revealed. The experimental research on ultrasonic vibration-assisted thermal bending and thermal deep drawing of CFRRMC sheet will be performed, and then the effects of forming process parameters on the thermal stamped CFRRMC parts quality and reasonable forming process parameters are obtained.