【作者】 孙开胜；

【导师】 王雷刚；

【作者基本信息】 江苏大学 ， 材料加工， 2008， 硕士

【摘要】 板料拉延成形过程及其数值模拟是一个非常活跃的研究领域,同时也是一个蕴藏着巨大经济效益的领域。随着有限元和计算机技术的发展,数值模拟已逐渐成为工艺分析及优化设计的有效工具。影响汽车覆盖件拉延成形的因素很多,如拉延型面、板料性能、凸凹模间隙、压边力大小、毛坯外形、拉深筋、摩擦润滑条件等等。其中,确定拉延毛坯的方法很多,有限元反向法相对于传统的拉延毛坯确定方法,在效率和精度上已经有了很大的进步,但其精度还远不能达到要求;而通过有限元增量法对毛坯的修正又无法实现定量的修正。本文提出了基于截面线变化的毛坯修正方法,可以对反向法获得的毛坯进行定量的修正。对于汽车覆盖件,在拉延毛坯的确定之前需要对覆盖件进行工艺设计和成形性分析。参数化的设计方法以及基于FASTFORM的快速成形性分析方法的使用,能够有效提高设计效率、节约时间。文中以江都宏运汽车厂某型号汽车后行李箱盖为例,完成了拉延型面的设计及成形性分析,并在理想冲压件的假设前提下,确定了对应的拉延毛坯。最后,应用DYNAFORM软件对设计好的行李箱盖拉延型面和确定的拉延毛坯进行了冲压过程的有限元仿真分析,并结合正交实验方法,对拉延筋高度、压边力大小、冲压速度、凸凹模间隙、摩擦系数等工艺参数进行分析优化,获得了满意结果。更多还原

【Abstract】 The drawing process of sheet metal and its numerical simulation is a very active research field, which has enormous economic benefits. With the development of FEM (Finite Element Method) and computer technology, the numerical simulation has become an effective tool in process analysis and optimization. There are many factors that influence the drawing process of automobile panels, such as the die face, blank properties, clearance between punch and die, the blank holder force, the blank shape, drawbeads, friction conditions and so on. Among the methods to determine the blank shape, the inverse FEM is superior to the traditional method in efficiency and accuracy, however its accuracy can’t satisfy the practical requirements and the modification on blank by increment finite element method is not quantitative. The blank modification based on section line change was proposed in the paper, which can make quantitative modification. Prior to the determination of blank shape, the process design and the forming analysis should be accomplished. Parametric design and rapid forming analysis based on the software FASTFORM can improve the design efficiency greatly. Taking the trunk lid of Jiangdu Hongyun Automobile Manufacture Factory as an example, the die face design and the forming analysis were accomplished. Under the premise of ideal blank outline, the corresponding blank was determined. After the die face design and the determination of blank shape, the stamping process was simulated by software DYNAFORM and the other process parameters, such as drawbeads, the blank holder force, punch velocity, clearance between punch and die, friction conditions and so on, were optimized based on orthogonal experiment method.更多还原